diff options
Diffstat (limited to 'pkg')
65 files changed, 406 insertions, 267 deletions
diff --git a/pkg/sentry/devices/memdev/full.go b/pkg/sentry/devices/memdev/full.go index c7e197691..af66fe4dc 100644 --- a/pkg/sentry/devices/memdev/full.go +++ b/pkg/sentry/devices/memdev/full.go @@ -42,6 +42,7 @@ type fullFD struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl vfs.DentryMetadataFileDescriptionImpl + vfs.NoLockFD } // Release implements vfs.FileDescriptionImpl.Release. diff --git a/pkg/sentry/devices/memdev/null.go b/pkg/sentry/devices/memdev/null.go index 33d060d02..92d3d71be 100644 --- a/pkg/sentry/devices/memdev/null.go +++ b/pkg/sentry/devices/memdev/null.go @@ -43,6 +43,7 @@ type nullFD struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl vfs.DentryMetadataFileDescriptionImpl + vfs.NoLockFD } // Release implements vfs.FileDescriptionImpl.Release. diff --git a/pkg/sentry/devices/memdev/random.go b/pkg/sentry/devices/memdev/random.go index acfa23149..6b81da5ef 100644 --- a/pkg/sentry/devices/memdev/random.go +++ b/pkg/sentry/devices/memdev/random.go @@ -48,6 +48,7 @@ type randomFD struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl vfs.DentryMetadataFileDescriptionImpl + vfs.NoLockFD // off is the "file offset". off is accessed using atomic memory // operations. diff --git a/pkg/sentry/devices/memdev/zero.go b/pkg/sentry/devices/memdev/zero.go index 3b1372b9e..c6f15054d 100644 --- a/pkg/sentry/devices/memdev/zero.go +++ b/pkg/sentry/devices/memdev/zero.go @@ -44,6 +44,7 @@ type zeroFD struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl vfs.DentryMetadataFileDescriptionImpl + vfs.NoLockFD } // Release implements vfs.FileDescriptionImpl.Release. diff --git a/pkg/sentry/fs/file.go b/pkg/sentry/fs/file.go index 2a278fbe3..ca41520b4 100644 --- a/pkg/sentry/fs/file.go +++ b/pkg/sentry/fs/file.go @@ -146,7 +146,7 @@ func (f *File) DecRef() { f.DecRefWithDestructor(func() { // Drop BSD style locks. lockRng := lock.LockRange{Start: 0, End: lock.LockEOF} - f.Dirent.Inode.LockCtx.BSD.UnlockRegion(lock.UniqueID(f.UniqueID), lockRng) + f.Dirent.Inode.LockCtx.BSD.UnlockRegion(f, lockRng) // Release resources held by the FileOperations. f.FileOperations.Release() diff --git a/pkg/sentry/fs/lock/lock.go b/pkg/sentry/fs/lock/lock.go index 926538d90..8a5d9c7eb 100644 --- a/pkg/sentry/fs/lock/lock.go +++ b/pkg/sentry/fs/lock/lock.go @@ -62,7 +62,7 @@ import ( type LockType int // UniqueID is a unique identifier of the holder of a regional file lock. -type UniqueID uint64 +type UniqueID interface{} const ( // ReadLock describes a POSIX regional file lock to be taken @@ -98,12 +98,7 @@ type Lock struct { // If len(Readers) > 0 then HasWriter must be false. Readers map[UniqueID]bool - // HasWriter indicates that this is a write lock held by a single - // UniqueID. - HasWriter bool - - // Writer is only valid if HasWriter is true. It identifies a - // single write lock holder. + // Writer holds the writer unique ID. It's nil if there are no writers. Writer UniqueID } @@ -186,7 +181,6 @@ func makeLock(uid UniqueID, t LockType) Lock { case ReadLock: value.Readers[uid] = true case WriteLock: - value.HasWriter = true value.Writer = uid default: panic(fmt.Sprintf("makeLock: invalid lock type %d", t)) @@ -196,10 +190,7 @@ func makeLock(uid UniqueID, t LockType) Lock { // isHeld returns true if uid is a holder of Lock. func (l Lock) isHeld(uid UniqueID) bool { - if l.HasWriter && l.Writer == uid { - return true - } - return l.Readers[uid] + return l.Writer == uid || l.Readers[uid] } // lock sets uid as a holder of a typed lock on Lock. @@ -214,20 +205,20 @@ func (l *Lock) lock(uid UniqueID, t LockType) { } // We cannot downgrade a write lock to a read lock unless the // uid is the same. - if l.HasWriter { + if l.Writer != nil { if l.Writer != uid { panic(fmt.Sprintf("lock: cannot downgrade write lock to read lock for uid %d, writer is %d", uid, l.Writer)) } // Ensure that there is only one reader if upgrading. l.Readers = make(map[UniqueID]bool) // Ensure that there is no longer a writer. - l.HasWriter = false + l.Writer = nil } l.Readers[uid] = true return case WriteLock: // If we are already the writer, then this is a no-op. - if l.HasWriter && l.Writer == uid { + if l.Writer == uid { return } // We can only upgrade a read lock to a write lock if there @@ -243,7 +234,6 @@ func (l *Lock) lock(uid UniqueID, t LockType) { } // Ensure that there is only a writer. l.Readers = make(map[UniqueID]bool) - l.HasWriter = true l.Writer = uid default: panic(fmt.Sprintf("lock: invalid lock type %d", t)) @@ -277,9 +267,8 @@ func (l LockSet) canLock(uid UniqueID, t LockType, r LockRange) bool { switch t { case ReadLock: return l.lockable(r, func(value Lock) bool { - // If there is no writer, there's no problem adding - // another reader. - if !value.HasWriter { + // If there is no writer, there's no problem adding another reader. + if value.Writer == nil { return true } // If there is a writer, then it must be the same uid @@ -289,10 +278,9 @@ func (l LockSet) canLock(uid UniqueID, t LockType, r LockRange) bool { case WriteLock: return l.lockable(r, func(value Lock) bool { // If there are only readers. - if !value.HasWriter { - // Then this uid can only take a write lock if - // this is a private upgrade, meaning that the - // only reader is uid. + if value.Writer == nil { + // Then this uid can only take a write lock if this is a private + // upgrade, meaning that the only reader is uid. return len(value.Readers) == 1 && value.Readers[uid] } // If the uid is already a writer on this region, then @@ -304,7 +292,8 @@ func (l LockSet) canLock(uid UniqueID, t LockType, r LockRange) bool { } } -// lock returns true if uid took a lock of type t on the entire range of LockRange. +// lock returns true if uid took a lock of type t on the entire range of +// LockRange. // // Preconditions: r.Start <= r.End (will panic otherwise). func (l *LockSet) lock(uid UniqueID, t LockType, r LockRange) bool { @@ -339,7 +328,7 @@ func (l *LockSet) lock(uid UniqueID, t LockType, r LockRange) bool { seg, _ = l.SplitUnchecked(seg, r.End) } - // Set the lock on the segment. This is guaranteed to + // Set the lock on the segment. This is guaranteed to // always be safe, given canLock above. value := seg.ValuePtr() value.lock(uid, t) @@ -386,7 +375,7 @@ func (l *LockSet) unlock(uid UniqueID, r LockRange) { value := seg.Value() var remove bool - if value.HasWriter && value.Writer == uid { + if value.Writer == uid { // If we are unlocking a writer, then since there can // only ever be one writer and no readers, then this // lock should always be removed from the set. diff --git a/pkg/sentry/fs/lock/lock_set_functions.go b/pkg/sentry/fs/lock/lock_set_functions.go index 8a3ace0c1..50a16e662 100644 --- a/pkg/sentry/fs/lock/lock_set_functions.go +++ b/pkg/sentry/fs/lock/lock_set_functions.go @@ -44,14 +44,9 @@ func (lockSetFunctions) Merge(r1 LockRange, val1 Lock, r2 LockRange, val2 Lock) return Lock{}, false } } - if val1.HasWriter != val2.HasWriter { + if val1.Writer != val2.Writer { return Lock{}, false } - if val1.HasWriter { - if val1.Writer != val2.Writer { - return Lock{}, false - } - } return val1, true } @@ -62,7 +57,6 @@ func (lockSetFunctions) Split(r LockRange, val Lock, split uint64) (Lock, Lock) for k, v := range val.Readers { val0.Readers[k] = v } - val0.HasWriter = val.HasWriter val0.Writer = val.Writer return val, val0 diff --git a/pkg/sentry/fs/lock/lock_test.go b/pkg/sentry/fs/lock/lock_test.go index ba002aeb7..fad90984b 100644 --- a/pkg/sentry/fs/lock/lock_test.go +++ b/pkg/sentry/fs/lock/lock_test.go @@ -42,9 +42,6 @@ func equals(e0, e1 []entry) bool { if !reflect.DeepEqual(e0[i].LockRange, e1[i].LockRange) { return false } - if e0[i].Lock.HasWriter != e1[i].Lock.HasWriter { - return false - } if e0[i].Lock.Writer != e1[i].Lock.Writer { return false } @@ -105,7 +102,7 @@ func TestCanLock(t *testing.T) { LockRange: LockRange{2048, 3072}, }, { - Lock: Lock{HasWriter: true, Writer: 1}, + Lock: Lock{Writer: 1}, LockRange: LockRange{3072, 4096}, }, }) @@ -241,7 +238,7 @@ func TestSetLock(t *testing.T) { // 0 max uint64 after: []entry{ { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{0, LockEOF}, }, }, @@ -254,7 +251,7 @@ func TestSetLock(t *testing.T) { // 0 max uint64 before: []entry{ { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{0, LockEOF}, }, }, @@ -273,7 +270,7 @@ func TestSetLock(t *testing.T) { LockRange: LockRange{0, 4096}, }, { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{4096, LockEOF}, }, }, @@ -301,7 +298,7 @@ func TestSetLock(t *testing.T) { // 0 4096 max uint64 after: []entry{ { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{0, 4096}, }, { @@ -318,7 +315,7 @@ func TestSetLock(t *testing.T) { // 0 max uint64 before: []entry{ { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{0, LockEOF}, }, }, @@ -550,7 +547,7 @@ func TestSetLock(t *testing.T) { LockRange: LockRange{0, 1024}, }, { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{1024, 4096}, }, { @@ -594,7 +591,7 @@ func TestSetLock(t *testing.T) { LockRange: LockRange{0, 1024}, }, { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{1024, 3072}, }, { @@ -633,7 +630,7 @@ func TestSetLock(t *testing.T) { // 0 1024 2048 4096 max uint64 before: []entry{ { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{0, 1024}, }, { @@ -663,11 +660,11 @@ func TestSetLock(t *testing.T) { // 0 1024 max uint64 after: []entry{ { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{0, 1024}, }, { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{1024, LockEOF}, }, }, @@ -675,28 +672,30 @@ func TestSetLock(t *testing.T) { } for _, test := range tests { - l := fill(test.before) + t.Run(test.name, func(t *testing.T) { + l := fill(test.before) - r := LockRange{Start: test.start, End: test.end} - success := l.lock(test.uid, test.lockType, r) - var got []entry - for seg := l.FirstSegment(); seg.Ok(); seg = seg.NextSegment() { - got = append(got, entry{ - Lock: seg.Value(), - LockRange: seg.Range(), - }) - } + r := LockRange{Start: test.start, End: test.end} + success := l.lock(test.uid, test.lockType, r) + var got []entry + for seg := l.FirstSegment(); seg.Ok(); seg = seg.NextSegment() { + got = append(got, entry{ + Lock: seg.Value(), + LockRange: seg.Range(), + }) + } - if success != test.success { - t.Errorf("%s: setlock(%v, %+v, %d, %d) got success %v, want %v", test.name, test.before, r, test.uid, test.lockType, success, test.success) - continue - } + if success != test.success { + t.Errorf("setlock(%v, %+v, %d, %d) got success %v, want %v", test.before, r, test.uid, test.lockType, success, test.success) + return + } - if success { - if !equals(got, test.after) { - t.Errorf("%s: got set %+v, want %+v", test.name, got, test.after) + if success { + if !equals(got, test.after) { + t.Errorf("got set %+v, want %+v", got, test.after) + } } - } + }) } } @@ -782,7 +781,7 @@ func TestUnlock(t *testing.T) { // 0 max uint64 before: []entry{ { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{0, LockEOF}, }, }, @@ -824,7 +823,7 @@ func TestUnlock(t *testing.T) { // 0 max uint64 before: []entry{ { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{0, LockEOF}, }, }, @@ -837,7 +836,7 @@ func TestUnlock(t *testing.T) { // 0 4096 max uint64 after: []entry{ { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{4096, LockEOF}, }, }, @@ -876,7 +875,7 @@ func TestUnlock(t *testing.T) { // 0 max uint64 before: []entry{ { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{0, LockEOF}, }, }, @@ -889,7 +888,7 @@ func TestUnlock(t *testing.T) { // 0 4096 after: []entry{ { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{0, 4096}, }, }, @@ -906,7 +905,7 @@ func TestUnlock(t *testing.T) { LockRange: LockRange{0, 1024}, }, { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{1024, 4096}, }, { @@ -974,7 +973,7 @@ func TestUnlock(t *testing.T) { // 0 1024 4096 max uint64 before: []entry{ { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{0, 1024}, }, { @@ -991,7 +990,7 @@ func TestUnlock(t *testing.T) { // 0 8 4096 max uint64 after: []entry{ { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{0, 8}, }, { @@ -1008,7 +1007,7 @@ func TestUnlock(t *testing.T) { // 0 1024 4096 max uint64 before: []entry{ { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{0, 1024}, }, { @@ -1025,7 +1024,7 @@ func TestUnlock(t *testing.T) { // 0 1024 4096 8192 max uint64 after: []entry{ { - Lock: Lock{HasWriter: true, Writer: 0}, + Lock: Lock{Writer: 0}, LockRange: LockRange{0, 1024}, }, { @@ -1041,19 +1040,21 @@ func TestUnlock(t *testing.T) { } for _, test := range tests { - l := fill(test.before) + t.Run(test.name, func(t *testing.T) { + l := fill(test.before) - r := LockRange{Start: test.start, End: test.end} - l.unlock(test.uid, r) - var got []entry - for seg := l.FirstSegment(); seg.Ok(); seg = seg.NextSegment() { - got = append(got, entry{ - Lock: seg.Value(), - LockRange: seg.Range(), - }) - } - if !equals(got, test.after) { - t.Errorf("%s: got set %+v, want %+v", test.name, got, test.after) - } + r := LockRange{Start: test.start, End: test.end} + l.unlock(test.uid, r) + var got []entry + for seg := l.FirstSegment(); seg.Ok(); seg = seg.NextSegment() { + got = append(got, entry{ + Lock: seg.Value(), + LockRange: seg.Range(), + }) + } + if !equals(got, test.after) { + t.Errorf("got set %+v, want %+v", got, test.after) + } + }) } } diff --git a/pkg/sentry/fsimpl/devpts/BUILD b/pkg/sentry/fsimpl/devpts/BUILD index 585764223..cf440dce8 100644 --- a/pkg/sentry/fsimpl/devpts/BUILD +++ b/pkg/sentry/fsimpl/devpts/BUILD @@ -23,6 +23,7 @@ go_library( "//pkg/sentry/kernel/auth", "//pkg/sentry/unimpl", "//pkg/sentry/vfs", + "//pkg/sentry/vfs/lock", "//pkg/sync", "//pkg/syserror", "//pkg/usermem", diff --git a/pkg/sentry/fsimpl/devpts/devpts.go b/pkg/sentry/fsimpl/devpts/devpts.go index c03c65445..9b0e0cca2 100644 --- a/pkg/sentry/fsimpl/devpts/devpts.go +++ b/pkg/sentry/fsimpl/devpts/devpts.go @@ -28,6 +28,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserror" ) @@ -116,6 +117,8 @@ type rootInode struct { kernfs.InodeNotSymlink kernfs.OrderedChildren + locks lock.FileLocks + // Keep a reference to this inode's dentry. dentry kernfs.Dentry @@ -183,7 +186,7 @@ func (i *rootInode) masterClose(t *Terminal) { // Open implements kernfs.Inode.Open. func (i *rootInode) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { - fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &i.OrderedChildren, &opts) + fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &i.OrderedChildren, &i.locks, &opts) if err != nil { return nil, err } diff --git a/pkg/sentry/fsimpl/devpts/master.go b/pkg/sentry/fsimpl/devpts/master.go index 7a7ce5d81..1d22adbe3 100644 --- a/pkg/sentry/fsimpl/devpts/master.go +++ b/pkg/sentry/fsimpl/devpts/master.go @@ -22,6 +22,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/unimpl" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" @@ -34,6 +35,8 @@ type masterInode struct { kernfs.InodeNotDirectory kernfs.InodeNotSymlink + locks lock.FileLocks + // Keep a reference to this inode's dentry. dentry kernfs.Dentry @@ -55,6 +58,7 @@ func (mi *masterInode) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vf inode: mi, t: t, } + fd.LockFD.Init(&mi.locks) if err := fd.vfsfd.Init(fd, opts.Flags, rp.Mount(), vfsd, &vfs.FileDescriptionOptions{}); err != nil { mi.DecRef() return nil, err @@ -85,6 +89,7 @@ func (mi *masterInode) SetStat(ctx context.Context, vfsfs *vfs.Filesystem, creds type masterFileDescription struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl + vfs.LockFD inode *masterInode t *Terminal diff --git a/pkg/sentry/fsimpl/devpts/slave.go b/pkg/sentry/fsimpl/devpts/slave.go index 526cd406c..7fe475080 100644 --- a/pkg/sentry/fsimpl/devpts/slave.go +++ b/pkg/sentry/fsimpl/devpts/slave.go @@ -21,6 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" @@ -33,6 +34,8 @@ type slaveInode struct { kernfs.InodeNotDirectory kernfs.InodeNotSymlink + locks lock.FileLocks + // Keep a reference to this inode's dentry. dentry kernfs.Dentry @@ -51,6 +54,7 @@ func (si *slaveInode) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs fd := &slaveFileDescription{ inode: si, } + fd.LockFD.Init(&si.locks) if err := fd.vfsfd.Init(fd, opts.Flags, rp.Mount(), vfsd, &vfs.FileDescriptionOptions{}); err != nil { si.DecRef() return nil, err @@ -91,6 +95,7 @@ func (si *slaveInode) SetStat(ctx context.Context, vfsfs *vfs.Filesystem, creds type slaveFileDescription struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl + vfs.LockFD inode *slaveInode } diff --git a/pkg/sentry/fsimpl/eventfd/eventfd.go b/pkg/sentry/fsimpl/eventfd/eventfd.go index c573d7935..d12d78b84 100644 --- a/pkg/sentry/fsimpl/eventfd/eventfd.go +++ b/pkg/sentry/fsimpl/eventfd/eventfd.go @@ -37,6 +37,7 @@ type EventFileDescription struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl vfs.DentryMetadataFileDescriptionImpl + vfs.NoLockFD // queue is used to notify interested parties when the event object // becomes readable or writable. diff --git a/pkg/sentry/fsimpl/ext/BUILD b/pkg/sentry/fsimpl/ext/BUILD index ff861d0fe..973fa0def 100644 --- a/pkg/sentry/fsimpl/ext/BUILD +++ b/pkg/sentry/fsimpl/ext/BUILD @@ -60,6 +60,7 @@ go_library( "//pkg/sentry/socket/unix/transport", "//pkg/sentry/syscalls/linux", "//pkg/sentry/vfs", + "//pkg/sentry/vfs/lock", "//pkg/sync", "//pkg/syserror", "//pkg/usermem", diff --git a/pkg/sentry/fsimpl/ext/file_description.go b/pkg/sentry/fsimpl/ext/file_description.go index 92f7da40d..90b086468 100644 --- a/pkg/sentry/fsimpl/ext/file_description.go +++ b/pkg/sentry/fsimpl/ext/file_description.go @@ -26,6 +26,7 @@ import ( type fileDescription struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl + vfs.LockFD } func (fd *fileDescription) filesystem() *filesystem { diff --git a/pkg/sentry/fsimpl/ext/inode.go b/pkg/sentry/fsimpl/ext/inode.go index 485f86f4b..e4b434b13 100644 --- a/pkg/sentry/fsimpl/ext/inode.go +++ b/pkg/sentry/fsimpl/ext/inode.go @@ -22,6 +22,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/fsimpl/ext/disklayout" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserror" ) @@ -54,6 +55,8 @@ type inode struct { // diskInode gives us access to the inode struct on disk. Immutable. diskInode disklayout.Inode + locks lock.FileLocks + // This is immutable. The first field of the implementations must have inode // as the first field to ensure temporality. impl interface{} @@ -157,6 +160,7 @@ func (in *inode) open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts *vfs.OpenOpt switch in.impl.(type) { case *regularFile: var fd regularFileFD + fd.LockFD.Init(&in.locks) if err := fd.vfsfd.Init(&fd, opts.Flags, mnt, vfsd, &vfs.FileDescriptionOptions{}); err != nil { return nil, err } @@ -168,6 +172,7 @@ func (in *inode) open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts *vfs.OpenOpt return nil, syserror.EISDIR } var fd directoryFD + fd.LockFD.Init(&in.locks) if err := fd.vfsfd.Init(&fd, opts.Flags, mnt, vfsd, &vfs.FileDescriptionOptions{}); err != nil { return nil, err } @@ -178,6 +183,7 @@ func (in *inode) open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts *vfs.OpenOpt return nil, syserror.ELOOP } var fd symlinkFD + fd.LockFD.Init(&in.locks) fd.vfsfd.Init(&fd, opts.Flags, mnt, vfsd, &vfs.FileDescriptionOptions{}) return &fd.vfsfd, nil default: diff --git a/pkg/sentry/fsimpl/ext/regular_file.go b/pkg/sentry/fsimpl/ext/regular_file.go index 30135ddb0..f7015c44f 100644 --- a/pkg/sentry/fsimpl/ext/regular_file.go +++ b/pkg/sentry/fsimpl/ext/regular_file.go @@ -77,6 +77,7 @@ func (in *inode) isRegular() bool { // vfs.FileDescriptionImpl. type regularFileFD struct { fileDescription + vfs.LockFD // off is the file offset. off is accessed using atomic memory operations. off int64 diff --git a/pkg/sentry/fsimpl/gofer/BUILD b/pkg/sentry/fsimpl/gofer/BUILD index f5f35a3bc..5cdeeaeb5 100644 --- a/pkg/sentry/fsimpl/gofer/BUILD +++ b/pkg/sentry/fsimpl/gofer/BUILD @@ -54,6 +54,7 @@ go_library( "//pkg/p9", "//pkg/safemem", "//pkg/sentry/fs/fsutil", + "//pkg/sentry/fs/lock", "//pkg/sentry/fsimpl/host", "//pkg/sentry/hostfd", "//pkg/sentry/kernel", @@ -68,6 +69,7 @@ go_library( "//pkg/sentry/socket/unix/transport", "//pkg/sentry/usage", "//pkg/sentry/vfs", + "//pkg/sentry/vfs/lock", "//pkg/syserr", "//pkg/syserror", "//pkg/unet", diff --git a/pkg/sentry/fsimpl/gofer/filesystem.go b/pkg/sentry/fsimpl/gofer/filesystem.go index 36e0e1856..40933b74b 100644 --- a/pkg/sentry/fsimpl/gofer/filesystem.go +++ b/pkg/sentry/fsimpl/gofer/filesystem.go @@ -801,6 +801,7 @@ func (d *dentry) openLocked(ctx context.Context, rp *vfs.ResolvingPath, opts *vf return nil, err } fd := ®ularFileFD{} + fd.LockFD.Init(&d.locks) if err := fd.vfsfd.Init(fd, opts.Flags, mnt, &d.vfsd, &vfs.FileDescriptionOptions{ AllowDirectIO: true, }); err != nil { @@ -826,6 +827,7 @@ func (d *dentry) openLocked(ctx context.Context, rp *vfs.ResolvingPath, opts *vf } } fd := &directoryFD{} + fd.LockFD.Init(&d.locks) if err := fd.vfsfd.Init(fd, opts.Flags, mnt, &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { return nil, err } @@ -842,7 +844,7 @@ func (d *dentry) openLocked(ctx context.Context, rp *vfs.ResolvingPath, opts *vf } case linux.S_IFIFO: if d.isSynthetic() { - return d.pipe.Open(ctx, mnt, &d.vfsd, opts.Flags) + return d.pipe.Open(ctx, mnt, &d.vfsd, opts.Flags, &d.locks) } } return d.openSpecialFileLocked(ctx, mnt, opts) @@ -902,7 +904,7 @@ retry: return nil, err } } - fd, err := newSpecialFileFD(h, mnt, d, opts.Flags) + fd, err := newSpecialFileFD(h, mnt, d, &d.locks, opts.Flags) if err != nil { h.close(ctx) return nil, err @@ -989,6 +991,7 @@ func (d *dentry) createAndOpenChildLocked(ctx context.Context, rp *vfs.Resolving var childVFSFD *vfs.FileDescription if useRegularFileFD { fd := ®ularFileFD{} + fd.LockFD.Init(&child.locks) if err := fd.vfsfd.Init(fd, opts.Flags, mnt, &child.vfsd, &vfs.FileDescriptionOptions{ AllowDirectIO: true, }); err != nil { @@ -1003,7 +1006,7 @@ func (d *dentry) createAndOpenChildLocked(ctx context.Context, rp *vfs.Resolving if fdobj != nil { h.fd = int32(fdobj.Release()) } - fd, err := newSpecialFileFD(h, mnt, child, opts.Flags) + fd, err := newSpecialFileFD(h, mnt, child, &d.locks, opts.Flags) if err != nil { h.close(ctx) return nil, err diff --git a/pkg/sentry/fsimpl/gofer/gofer.go b/pkg/sentry/fsimpl/gofer/gofer.go index 3f3bd56f0..0d88a328e 100644 --- a/pkg/sentry/fsimpl/gofer/gofer.go +++ b/pkg/sentry/fsimpl/gofer/gofer.go @@ -45,6 +45,7 @@ import ( "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/p9" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" + fslock "gvisor.dev/gvisor/pkg/sentry/fs/lock" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/kernel/pipe" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" @@ -52,6 +53,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/pgalloc" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/unet" "gvisor.dev/gvisor/pkg/usermem" @@ -662,6 +664,8 @@ type dentry struct { // If this dentry represents a synthetic named pipe, pipe is the pipe // endpoint bound to this file. pipe *pipe.VFSPipe + + locks lock.FileLocks } // dentryAttrMask returns a p9.AttrMask enabling all attributes used by the @@ -1366,6 +1370,9 @@ func (d *dentry) decLinks() { type fileDescription struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl + vfs.LockFD + + lockLogging sync.Once } func (fd *fileDescription) filesystem() *filesystem { @@ -1416,3 +1423,19 @@ func (fd *fileDescription) Setxattr(ctx context.Context, opts vfs.SetxattrOption func (fd *fileDescription) Removexattr(ctx context.Context, name string) error { return fd.dentry().removexattr(ctx, auth.CredentialsFromContext(ctx), name) } + +// LockBSD implements vfs.FileDescriptionImpl.LockBSD. +func (fd *fileDescription) LockBSD(ctx context.Context, uid fslock.UniqueID, t fslock.LockType, block fslock.Blocker) error { + fd.lockLogging.Do(func() { + log.Infof("File lock using gofer file handled internally.") + }) + return fd.LockFD.LockBSD(ctx, uid, t, block) +} + +// LockPOSIX implements vfs.FileDescriptionImpl.LockPOSIX. +func (fd *fileDescription) LockPOSIX(ctx context.Context, uid fslock.UniqueID, t fslock.LockType, rng fslock.LockRange, block fslock.Blocker) error { + fd.lockLogging.Do(func() { + log.Infof("Range lock using gofer file handled internally.") + }) + return fd.LockFD.LockPOSIX(ctx, uid, t, rng, block) +} diff --git a/pkg/sentry/fsimpl/gofer/special_file.go b/pkg/sentry/fsimpl/gofer/special_file.go index ff6126b87..289efdd25 100644 --- a/pkg/sentry/fsimpl/gofer/special_file.go +++ b/pkg/sentry/fsimpl/gofer/special_file.go @@ -22,6 +22,7 @@ import ( "gvisor.dev/gvisor/pkg/fdnotifier" "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" @@ -51,7 +52,7 @@ type specialFileFD struct { off int64 } -func newSpecialFileFD(h handle, mnt *vfs.Mount, d *dentry, flags uint32) (*specialFileFD, error) { +func newSpecialFileFD(h handle, mnt *vfs.Mount, d *dentry, locks *lock.FileLocks, flags uint32) (*specialFileFD, error) { ftype := d.fileType() seekable := ftype == linux.S_IFREG mayBlock := ftype == linux.S_IFIFO || ftype == linux.S_IFSOCK @@ -60,6 +61,7 @@ func newSpecialFileFD(h handle, mnt *vfs.Mount, d *dentry, flags uint32) (*speci seekable: seekable, mayBlock: mayBlock, } + fd.LockFD.Init(locks) if mayBlock && h.fd >= 0 { if err := fdnotifier.AddFD(h.fd, &fd.queue); err != nil { return nil, err diff --git a/pkg/sentry/fsimpl/host/BUILD b/pkg/sentry/fsimpl/host/BUILD index ca0fe6d2b..54f16ad63 100644 --- a/pkg/sentry/fsimpl/host/BUILD +++ b/pkg/sentry/fsimpl/host/BUILD @@ -39,6 +39,7 @@ go_library( "//pkg/sentry/unimpl", "//pkg/sentry/uniqueid", "//pkg/sentry/vfs", + "//pkg/sentry/vfs/lock", "//pkg/sync", "//pkg/syserr", "//pkg/syserror", diff --git a/pkg/sentry/fsimpl/host/host.go b/pkg/sentry/fsimpl/host/host.go index 18b127521..5ec5100b8 100644 --- a/pkg/sentry/fsimpl/host/host.go +++ b/pkg/sentry/fsimpl/host/host.go @@ -34,6 +34,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/memmap" unixsocket "gvisor.dev/gvisor/pkg/sentry/socket/unix" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" @@ -182,6 +183,8 @@ type inode struct { kernfs.InodeNotDirectory kernfs.InodeNotSymlink + locks lock.FileLocks + // When the reference count reaches zero, the host fd is closed. refs.AtomicRefCount @@ -468,7 +471,7 @@ func (i *inode) open(ctx context.Context, d *vfs.Dentry, mnt *vfs.Mount, flags u return nil, err } // Currently, we only allow Unix sockets to be imported. - return unixsocket.NewFileDescription(ep, ep.Type(), flags, mnt, d) + return unixsocket.NewFileDescription(ep, ep.Type(), flags, mnt, d, &i.locks) } // TODO(gvisor.dev/issue/1672): Whitelist specific file types here, so that @@ -478,6 +481,7 @@ func (i *inode) open(ctx context.Context, d *vfs.Dentry, mnt *vfs.Mount, flags u fileDescription: fileDescription{inode: i}, termios: linux.DefaultSlaveTermios, } + fd.LockFD.Init(&i.locks) vfsfd := &fd.vfsfd if err := vfsfd.Init(fd, flags, mnt, d, &vfs.FileDescriptionOptions{}); err != nil { return nil, err @@ -486,6 +490,7 @@ func (i *inode) open(ctx context.Context, d *vfs.Dentry, mnt *vfs.Mount, flags u } fd := &fileDescription{inode: i} + fd.LockFD.Init(&i.locks) vfsfd := &fd.vfsfd if err := vfsfd.Init(fd, flags, mnt, d, &vfs.FileDescriptionOptions{}); err != nil { return nil, err @@ -497,6 +502,7 @@ func (i *inode) open(ctx context.Context, d *vfs.Dentry, mnt *vfs.Mount, flags u type fileDescription struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl + vfs.LockFD // inode is vfsfd.Dentry().Impl().(*kernfs.Dentry).Inode().(*inode), but // cached to reduce indirections and casting. fileDescription does not hold diff --git a/pkg/sentry/fsimpl/kernfs/BUILD b/pkg/sentry/fsimpl/kernfs/BUILD index ef34cb28a..0299dbde9 100644 --- a/pkg/sentry/fsimpl/kernfs/BUILD +++ b/pkg/sentry/fsimpl/kernfs/BUILD @@ -49,6 +49,7 @@ go_library( "//pkg/sentry/memmap", "//pkg/sentry/socket/unix/transport", "//pkg/sentry/vfs", + "//pkg/sentry/vfs/lock", "//pkg/sync", "//pkg/syserror", "//pkg/usermem", @@ -67,6 +68,7 @@ go_test( "//pkg/sentry/fsimpl/testutil", "//pkg/sentry/kernel/auth", "//pkg/sentry/vfs", + "//pkg/sentry/vfs/lock", "//pkg/syserror", "//pkg/usermem", "@com_github_google_go-cmp//cmp:go_default_library", diff --git a/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go b/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go index 1568a9d49..6418de0a3 100644 --- a/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go +++ b/pkg/sentry/fsimpl/kernfs/dynamic_bytes_file.go @@ -21,6 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" ) @@ -38,7 +39,8 @@ type DynamicBytesFile struct { InodeNotDirectory InodeNotSymlink - data vfs.DynamicBytesSource + locks lock.FileLocks + data vfs.DynamicBytesSource } var _ Inode = (*DynamicBytesFile)(nil) @@ -55,7 +57,7 @@ func (f *DynamicBytesFile) Init(creds *auth.Credentials, devMajor, devMinor uint // Open implements Inode.Open. func (f *DynamicBytesFile) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { fd := &DynamicBytesFD{} - if err := fd.Init(rp.Mount(), vfsd, f.data, opts.Flags); err != nil { + if err := fd.Init(rp.Mount(), vfsd, f.data, &f.locks, opts.Flags); err != nil { return nil, err } return &fd.vfsfd, nil @@ -77,13 +79,15 @@ func (*DynamicBytesFile) SetStat(context.Context, *vfs.Filesystem, *auth.Credent type DynamicBytesFD struct { vfs.FileDescriptionDefaultImpl vfs.DynamicBytesFileDescriptionImpl + vfs.LockFD vfsfd vfs.FileDescription inode Inode } // Init initializes a DynamicBytesFD. -func (fd *DynamicBytesFD) Init(m *vfs.Mount, d *vfs.Dentry, data vfs.DynamicBytesSource, flags uint32) error { +func (fd *DynamicBytesFD) Init(m *vfs.Mount, d *vfs.Dentry, data vfs.DynamicBytesSource, locks *lock.FileLocks, flags uint32) error { + fd.LockFD.Init(locks) if err := fd.vfsfd.Init(fd, flags, m, d, &vfs.FileDescriptionOptions{}); err != nil { return err } diff --git a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go index 8284e76a7..33a5968ca 100644 --- a/pkg/sentry/fsimpl/kernfs/fd_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/fd_impl_util.go @@ -22,6 +22,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" @@ -42,6 +43,7 @@ import ( type GenericDirectoryFD struct { vfs.FileDescriptionDefaultImpl vfs.DirectoryFileDescriptionDefaultImpl + vfs.LockFD vfsfd vfs.FileDescription children *OrderedChildren @@ -55,9 +57,9 @@ type GenericDirectoryFD struct { // NewGenericDirectoryFD creates a new GenericDirectoryFD and returns its // dentry. -func NewGenericDirectoryFD(m *vfs.Mount, d *vfs.Dentry, children *OrderedChildren, opts *vfs.OpenOptions) (*GenericDirectoryFD, error) { +func NewGenericDirectoryFD(m *vfs.Mount, d *vfs.Dentry, children *OrderedChildren, locks *lock.FileLocks, opts *vfs.OpenOptions) (*GenericDirectoryFD, error) { fd := &GenericDirectoryFD{} - if err := fd.Init(children, opts); err != nil { + if err := fd.Init(children, locks, opts); err != nil { return nil, err } if err := fd.vfsfd.Init(fd, opts.Flags, m, d, &vfs.FileDescriptionOptions{}); err != nil { @@ -69,11 +71,12 @@ func NewGenericDirectoryFD(m *vfs.Mount, d *vfs.Dentry, children *OrderedChildre // Init initializes a GenericDirectoryFD. Use it when overriding // GenericDirectoryFD. Caller must call fd.VFSFileDescription.Init() with the // correct implementation. -func (fd *GenericDirectoryFD) Init(children *OrderedChildren, opts *vfs.OpenOptions) error { +func (fd *GenericDirectoryFD) Init(children *OrderedChildren, locks *lock.FileLocks, opts *vfs.OpenOptions) error { if vfs.AccessTypesForOpenFlags(opts)&vfs.MayWrite != 0 { // Can't open directories for writing. return syserror.EISDIR } + fd.LockFD.Init(locks) fd.children = children return nil } diff --git a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go index 982daa2e6..0e4927215 100644 --- a/pkg/sentry/fsimpl/kernfs/inode_impl_util.go +++ b/pkg/sentry/fsimpl/kernfs/inode_impl_util.go @@ -23,6 +23,7 @@ import ( "gvisor.dev/gvisor/pkg/refs" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" ) @@ -555,6 +556,8 @@ type StaticDirectory struct { InodeAttrs InodeNoDynamicLookup OrderedChildren + + locks lock.FileLocks } var _ Inode = (*StaticDirectory)(nil) @@ -584,7 +587,7 @@ func (s *StaticDirectory) Init(creds *auth.Credentials, devMajor, devMinor uint3 // Open implements kernfs.Inode. func (s *StaticDirectory) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { - fd, err := NewGenericDirectoryFD(rp.Mount(), vfsd, &s.OrderedChildren, &opts) + fd, err := NewGenericDirectoryFD(rp.Mount(), vfsd, &s.OrderedChildren, &s.locks, &opts) if err != nil { return nil, err } diff --git a/pkg/sentry/fsimpl/kernfs/kernfs_test.go b/pkg/sentry/fsimpl/kernfs/kernfs_test.go index 412cf6ac9..6749facf7 100644 --- a/pkg/sentry/fsimpl/kernfs/kernfs_test.go +++ b/pkg/sentry/fsimpl/kernfs/kernfs_test.go @@ -27,6 +27,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/fsimpl/testutil" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" ) @@ -100,8 +101,10 @@ type readonlyDir struct { kernfs.InodeNotSymlink kernfs.InodeNoDynamicLookup kernfs.InodeDirectoryNoNewChildren - kernfs.OrderedChildren + + locks lock.FileLocks + dentry kernfs.Dentry } @@ -117,7 +120,7 @@ func (fs *filesystem) newReadonlyDir(creds *auth.Credentials, mode linux.FileMod } func (d *readonlyDir) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { - fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &d.OrderedChildren, &opts) + fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &d.OrderedChildren, &d.locks, &opts) if err != nil { return nil, err } @@ -128,10 +131,12 @@ type dir struct { attrs kernfs.InodeNotSymlink kernfs.InodeNoDynamicLookup + kernfs.OrderedChildren + + locks lock.FileLocks fs *filesystem dentry kernfs.Dentry - kernfs.OrderedChildren } func (fs *filesystem) newDir(creds *auth.Credentials, mode linux.FileMode, contents map[string]*kernfs.Dentry) *kernfs.Dentry { @@ -147,7 +152,7 @@ func (fs *filesystem) newDir(creds *auth.Credentials, mode linux.FileMode, conte } func (d *dir) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { - fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &d.OrderedChildren, &opts) + fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &d.OrderedChildren, &d.locks, &opts) if err != nil { return nil, err } diff --git a/pkg/sentry/fsimpl/pipefs/BUILD b/pkg/sentry/fsimpl/pipefs/BUILD index 5950a2d59..c618dbe6c 100644 --- a/pkg/sentry/fsimpl/pipefs/BUILD +++ b/pkg/sentry/fsimpl/pipefs/BUILD @@ -15,6 +15,7 @@ go_library( "//pkg/sentry/kernel/pipe", "//pkg/sentry/kernel/time", "//pkg/sentry/vfs", + "//pkg/sentry/vfs/lock", "//pkg/syserror", "//pkg/usermem", ], diff --git a/pkg/sentry/fsimpl/pipefs/pipefs.go b/pkg/sentry/fsimpl/pipefs/pipefs.go index cab771211..e4dabaa33 100644 --- a/pkg/sentry/fsimpl/pipefs/pipefs.go +++ b/pkg/sentry/fsimpl/pipefs/pipefs.go @@ -27,6 +27,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel/pipe" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" ) @@ -81,7 +82,8 @@ type inode struct { kernfs.InodeNotSymlink kernfs.InodeNoopRefCount - pipe *pipe.VFSPipe + locks lock.FileLocks + pipe *pipe.VFSPipe ino uint64 uid auth.KUID @@ -147,7 +149,7 @@ func (i *inode) SetStat(ctx context.Context, vfsfs *vfs.Filesystem, creds *auth. // Open implements kernfs.Inode.Open. func (i *inode) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { - return i.pipe.Open(ctx, rp.Mount(), vfsd, opts.Flags) + return i.pipe.Open(ctx, rp.Mount(), vfsd, opts.Flags, &i.locks) } // NewConnectedPipeFDs returns a pair of FileDescriptions representing the read diff --git a/pkg/sentry/fsimpl/proc/BUILD b/pkg/sentry/fsimpl/proc/BUILD index 17c1342b5..351ba4ee9 100644 --- a/pkg/sentry/fsimpl/proc/BUILD +++ b/pkg/sentry/fsimpl/proc/BUILD @@ -35,6 +35,7 @@ go_library( "//pkg/sentry/socket/unix/transport", "//pkg/sentry/usage", "//pkg/sentry/vfs", + "//pkg/sentry/vfs/lock", "//pkg/syserror", "//pkg/tcpip/header", "//pkg/usermem", diff --git a/pkg/sentry/fsimpl/proc/subtasks.go b/pkg/sentry/fsimpl/proc/subtasks.go index 36a911db4..e2cdb7ee9 100644 --- a/pkg/sentry/fsimpl/proc/subtasks.go +++ b/pkg/sentry/fsimpl/proc/subtasks.go @@ -24,6 +24,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserror" ) @@ -37,6 +38,8 @@ type subtasksInode struct { kernfs.OrderedChildren kernfs.AlwaysValid + locks lock.FileLocks + fs *filesystem task *kernel.Task pidns *kernel.PIDNamespace @@ -153,7 +156,7 @@ func (fd *subtasksFD) SetStat(ctx context.Context, opts vfs.SetStatOptions) erro // Open implements kernfs.Inode. func (i *subtasksInode) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { fd := &subtasksFD{task: i.task} - if err := fd.Init(&i.OrderedChildren, &opts); err != nil { + if err := fd.Init(&i.OrderedChildren, &i.locks, &opts); err != nil { return nil, err } if err := fd.VFSFileDescription().Init(fd, opts.Flags, rp.Mount(), vfsd, &vfs.FileDescriptionOptions{}); err != nil { diff --git a/pkg/sentry/fsimpl/proc/task.go b/pkg/sentry/fsimpl/proc/task.go index 482055db1..44078a765 100644 --- a/pkg/sentry/fsimpl/proc/task.go +++ b/pkg/sentry/fsimpl/proc/task.go @@ -25,6 +25,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/mm" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserror" ) @@ -38,6 +39,8 @@ type taskInode struct { kernfs.InodeAttrs kernfs.OrderedChildren + locks lock.FileLocks + task *kernel.Task } @@ -103,7 +106,7 @@ func (i *taskInode) Valid(ctx context.Context) bool { // Open implements kernfs.Inode. func (i *taskInode) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { - fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &i.OrderedChildren, &opts) + fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &i.OrderedChildren, &i.locks, &opts) if err != nil { return nil, err } diff --git a/pkg/sentry/fsimpl/proc/task_fds.go b/pkg/sentry/fsimpl/proc/task_fds.go index 44ccc9e4a..ef6c1d04f 100644 --- a/pkg/sentry/fsimpl/proc/task_fds.go +++ b/pkg/sentry/fsimpl/proc/task_fds.go @@ -27,6 +27,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserror" ) @@ -53,6 +54,8 @@ func taskFDExists(t *kernel.Task, fd int32) bool { } type fdDir struct { + locks lock.FileLocks + fs *filesystem task *kernel.Task @@ -143,7 +146,7 @@ func (i *fdDirInode) Lookup(ctx context.Context, name string) (*vfs.Dentry, erro // Open implements kernfs.Inode. func (i *fdDirInode) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { - fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &i.OrderedChildren, &opts) + fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &i.OrderedChildren, &i.locks, &opts) if err != nil { return nil, err } @@ -270,7 +273,7 @@ func (i *fdInfoDirInode) Lookup(ctx context.Context, name string) (*vfs.Dentry, // Open implements kernfs.Inode. func (i *fdInfoDirInode) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { - fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &i.OrderedChildren, &opts) + fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &i.OrderedChildren, &i.locks, &opts) if err != nil { return nil, err } diff --git a/pkg/sentry/fsimpl/proc/task_files.go b/pkg/sentry/fsimpl/proc/task_files.go index 2f297e48a..e5eaa91cd 100644 --- a/pkg/sentry/fsimpl/proc/task_files.go +++ b/pkg/sentry/fsimpl/proc/task_files.go @@ -30,6 +30,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/mm" "gvisor.dev/gvisor/pkg/sentry/usage" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" ) @@ -775,6 +776,8 @@ type namespaceInode struct { kernfs.InodeNoopRefCount kernfs.InodeNotDirectory kernfs.InodeNotSymlink + + locks lock.FileLocks } var _ kernfs.Inode = (*namespaceInode)(nil) @@ -791,6 +794,7 @@ func (i *namespaceInode) Init(creds *auth.Credentials, devMajor, devMinor uint32 func (i *namespaceInode) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { fd := &namespaceFD{inode: i} i.IncRef() + fd.LockFD.Init(&i.locks) if err := fd.vfsfd.Init(fd, opts.Flags, rp.Mount(), vfsd, &vfs.FileDescriptionOptions{}); err != nil { return nil, err } @@ -801,6 +805,7 @@ func (i *namespaceInode) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd * // /proc/[pid]/ns/*. type namespaceFD struct { vfs.FileDescriptionDefaultImpl + vfs.LockFD vfsfd vfs.FileDescription inode *namespaceInode @@ -825,8 +830,3 @@ func (fd *namespaceFD) SetStat(ctx context.Context, opts vfs.SetStatOptions) err func (fd *namespaceFD) Release() { fd.inode.DecRef() } - -// OnClose implements FileDescriptionImpl. -func (*namespaceFD) OnClose(context.Context) error { - return nil -} diff --git a/pkg/sentry/fsimpl/proc/tasks.go b/pkg/sentry/fsimpl/proc/tasks.go index b51d43954..58c8b9d05 100644 --- a/pkg/sentry/fsimpl/proc/tasks.go +++ b/pkg/sentry/fsimpl/proc/tasks.go @@ -25,6 +25,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserror" ) @@ -43,6 +44,8 @@ type tasksInode struct { kernfs.OrderedChildren kernfs.AlwaysValid + locks lock.FileLocks + fs *filesystem pidns *kernel.PIDNamespace @@ -197,7 +200,7 @@ func (i *tasksInode) IterDirents(ctx context.Context, cb vfs.IterDirentsCallback // Open implements kernfs.Inode. func (i *tasksInode) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { - fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &i.OrderedChildren, &opts) + fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &i.OrderedChildren, &i.locks, &opts) if err != nil { return nil, err } diff --git a/pkg/sentry/fsimpl/signalfd/signalfd.go b/pkg/sentry/fsimpl/signalfd/signalfd.go index d29ef3f83..242ba9b5d 100644 --- a/pkg/sentry/fsimpl/signalfd/signalfd.go +++ b/pkg/sentry/fsimpl/signalfd/signalfd.go @@ -31,6 +31,7 @@ type SignalFileDescription struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl vfs.DentryMetadataFileDescriptionImpl + vfs.NoLockFD // target is the original signal target task. // diff --git a/pkg/sentry/fsimpl/sys/BUILD b/pkg/sentry/fsimpl/sys/BUILD index a741e2bb6..237f17def 100644 --- a/pkg/sentry/fsimpl/sys/BUILD +++ b/pkg/sentry/fsimpl/sys/BUILD @@ -15,6 +15,7 @@ go_library( "//pkg/sentry/kernel", "//pkg/sentry/kernel/auth", "//pkg/sentry/vfs", + "//pkg/sentry/vfs/lock", "//pkg/syserror", ], ) diff --git a/pkg/sentry/fsimpl/sys/sys.go b/pkg/sentry/fsimpl/sys/sys.go index 0af373604..b84463d3a 100644 --- a/pkg/sentry/fsimpl/sys/sys.go +++ b/pkg/sentry/fsimpl/sys/sys.go @@ -25,6 +25,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserror" ) @@ -98,8 +99,10 @@ type dir struct { kernfs.InodeNoDynamicLookup kernfs.InodeNotSymlink kernfs.InodeDirectoryNoNewChildren - kernfs.OrderedChildren + + locks lock.FileLocks + dentry kernfs.Dentry } @@ -121,7 +124,7 @@ func (*dir) SetStat(context.Context, *vfs.Filesystem, *auth.Credentials, vfs.Set // Open implements kernfs.Inode.Open. func (d *dir) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { - fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &d.OrderedChildren, &opts) + fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), vfsd, &d.OrderedChildren, &d.locks, &opts) if err != nil { return nil, err } diff --git a/pkg/sentry/fsimpl/timerfd/timerfd.go b/pkg/sentry/fsimpl/timerfd/timerfd.go index 60c92d626..2dc90d484 100644 --- a/pkg/sentry/fsimpl/timerfd/timerfd.go +++ b/pkg/sentry/fsimpl/timerfd/timerfd.go @@ -32,6 +32,7 @@ type TimerFileDescription struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl vfs.DentryMetadataFileDescriptionImpl + vfs.NoLockFD events waiter.Queue timer *ktime.Timer diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index e801680e8..72399b321 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -399,6 +399,7 @@ func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, opts *vfs.Open switch impl := d.inode.impl.(type) { case *regularFile: var fd regularFileFD + fd.LockFD.Init(&d.inode.locks) if err := fd.vfsfd.Init(&fd, opts.Flags, rp.Mount(), &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { return nil, err } @@ -414,15 +415,16 @@ func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, opts *vfs.Open return nil, syserror.EISDIR } var fd directoryFD + fd.LockFD.Init(&d.inode.locks) if err := fd.vfsfd.Init(&fd, opts.Flags, rp.Mount(), &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { return nil, err } return &fd.vfsfd, nil case *symlink: - // Can't open symlinks without O_PATH (which is unimplemented). + // TODO(gvisor.dev/issue/2782): Can't open symlinks without O_PATH. return nil, syserror.ELOOP case *namedPipe: - return impl.pipe.Open(ctx, rp.Mount(), &d.vfsd, opts.Flags) + return impl.pipe.Open(ctx, rp.Mount(), &d.vfsd, opts.Flags, &d.inode.locks) case *deviceFile: return rp.VirtualFilesystem().OpenDeviceSpecialFile(ctx, rp.Mount(), &d.vfsd, impl.kind, impl.major, impl.minor, opts) case *socketFile: diff --git a/pkg/sentry/fsimpl/tmpfs/regular_file.go b/pkg/sentry/fsimpl/tmpfs/regular_file.go index 4f2ae04d2..77447b32c 100644 --- a/pkg/sentry/fsimpl/tmpfs/regular_file.go +++ b/pkg/sentry/fsimpl/tmpfs/regular_file.go @@ -25,7 +25,6 @@ import ( "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" - "gvisor.dev/gvisor/pkg/sentry/fs/lock" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/pgalloc" @@ -366,28 +365,6 @@ func (fd *regularFileFD) Sync(ctx context.Context) error { return nil } -// LockBSD implements vfs.FileDescriptionImpl.LockBSD. -func (fd *regularFileFD) LockBSD(ctx context.Context, uid lock.UniqueID, t lock.LockType, block lock.Blocker) error { - return fd.inode().lockBSD(uid, t, block) -} - -// UnlockBSD implements vfs.FileDescriptionImpl.UnlockBSD. -func (fd *regularFileFD) UnlockBSD(ctx context.Context, uid lock.UniqueID) error { - fd.inode().unlockBSD(uid) - return nil -} - -// LockPOSIX implements vfs.FileDescriptionImpl.LockPOSIX. -func (fd *regularFileFD) LockPOSIX(ctx context.Context, uid lock.UniqueID, t lock.LockType, rng lock.LockRange, block lock.Blocker) error { - return fd.inode().lockPOSIX(uid, t, rng, block) -} - -// UnlockPOSIX implements vfs.FileDescriptionImpl.UnlockPOSIX. -func (fd *regularFileFD) UnlockPOSIX(ctx context.Context, uid lock.UniqueID, rng lock.LockRange) error { - fd.inode().unlockPOSIX(uid, rng) - return nil -} - // ConfigureMMap implements vfs.FileDescriptionImpl.ConfigureMMap. func (fd *regularFileFD) ConfigureMMap(ctx context.Context, opts *memmap.MMapOpts) error { file := fd.inode().impl.(*regularFile) diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs.go b/pkg/sentry/fsimpl/tmpfs/tmpfs.go index 7ce1b86c7..71a7522af 100644 --- a/pkg/sentry/fsimpl/tmpfs/tmpfs.go +++ b/pkg/sentry/fsimpl/tmpfs/tmpfs.go @@ -36,7 +36,6 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/context" - fslock "gvisor.dev/gvisor/pkg/sentry/fs/lock" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/pgalloc" @@ -311,7 +310,6 @@ type inode struct { ctime int64 // nanoseconds mtime int64 // nanoseconds - // Advisory file locks, which lock at the inode level. locks lock.FileLocks // Inotify watches for this inode. @@ -539,44 +537,6 @@ func (i *inode) setStat(ctx context.Context, creds *auth.Credentials, stat *linu return nil } -// TODO(gvisor.dev/issue/1480): support file locking for file types other than regular. -func (i *inode) lockBSD(uid fslock.UniqueID, t fslock.LockType, block fslock.Blocker) error { - switch i.impl.(type) { - case *regularFile: - return i.locks.LockBSD(uid, t, block) - } - return syserror.EBADF -} - -// TODO(gvisor.dev/issue/1480): support file locking for file types other than regular. -func (i *inode) unlockBSD(uid fslock.UniqueID) error { - switch i.impl.(type) { - case *regularFile: - i.locks.UnlockBSD(uid) - return nil - } - return syserror.EBADF -} - -// TODO(gvisor.dev/issue/1480): support file locking for file types other than regular. -func (i *inode) lockPOSIX(uid fslock.UniqueID, t fslock.LockType, rng fslock.LockRange, block fslock.Blocker) error { - switch i.impl.(type) { - case *regularFile: - return i.locks.LockPOSIX(uid, t, rng, block) - } - return syserror.EBADF -} - -// TODO(gvisor.dev/issue/1480): support file locking for file types other than regular. -func (i *inode) unlockPOSIX(uid fslock.UniqueID, rng fslock.LockRange) error { - switch i.impl.(type) { - case *regularFile: - i.locks.UnlockPOSIX(uid, rng) - return nil - } - return syserror.EBADF -} - // allocatedBlocksForSize returns the number of 512B blocks needed to // accommodate the given size in bytes, as appropriate for struct // stat::st_blocks and struct statx::stx_blocks. (Note that this 512B block @@ -708,6 +668,7 @@ func (i *inode) userXattrSupported() bool { type fileDescription struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl + vfs.LockFD } func (fd *fileDescription) filesystem() *filesystem { diff --git a/pkg/sentry/kernel/fd_table.go b/pkg/sentry/kernel/fd_table.go index dbfcef0fa..b35afafe3 100644 --- a/pkg/sentry/kernel/fd_table.go +++ b/pkg/sentry/kernel/fd_table.go @@ -80,9 +80,6 @@ type FDTable struct { refs.AtomicRefCount k *Kernel - // uid is a unique identifier. - uid uint64 - // mu protects below. mu sync.Mutex `state:"nosave"` @@ -130,7 +127,7 @@ func (f *FDTable) loadDescriptorTable(m map[int32]descriptor) { // drop drops the table reference. func (f *FDTable) drop(file *fs.File) { // Release locks. - file.Dirent.Inode.LockCtx.Posix.UnlockRegion(lock.UniqueID(f.uid), lock.LockRange{0, lock.LockEOF}) + file.Dirent.Inode.LockCtx.Posix.UnlockRegion(f, lock.LockRange{0, lock.LockEOF}) // Send inotify events. d := file.Dirent @@ -164,17 +161,9 @@ func (f *FDTable) dropVFS2(file *vfs.FileDescription) { file.DecRef() } -// ID returns a unique identifier for this FDTable. -func (f *FDTable) ID() uint64 { - return f.uid -} - // NewFDTable allocates a new FDTable that may be used by tasks in k. func (k *Kernel) NewFDTable() *FDTable { - f := &FDTable{ - k: k, - uid: atomic.AddUint64(&k.fdMapUids, 1), - } + f := &FDTable{k: k} f.init() return f } diff --git a/pkg/sentry/kernel/kernel.go b/pkg/sentry/kernel/kernel.go index 5efeb3767..bcbeb6a39 100644 --- a/pkg/sentry/kernel/kernel.go +++ b/pkg/sentry/kernel/kernel.go @@ -194,11 +194,6 @@ type Kernel struct { // cpuClockTickerSetting is protected by runningTasksMu. cpuClockTickerSetting ktime.Setting - // fdMapUids is an ever-increasing counter for generating FDTable uids. - // - // fdMapUids is mutable, and is accessed using atomic memory operations. - fdMapUids uint64 - // uniqueID is used to generate unique identifiers. // // uniqueID is mutable, and is accessed using atomic memory operations. diff --git a/pkg/sentry/kernel/pipe/BUILD b/pkg/sentry/kernel/pipe/BUILD index 7bfa9075a..0db546b98 100644 --- a/pkg/sentry/kernel/pipe/BUILD +++ b/pkg/sentry/kernel/pipe/BUILD @@ -27,6 +27,7 @@ go_library( "//pkg/sentry/fs", "//pkg/sentry/fs/fsutil", "//pkg/sentry/vfs", + "//pkg/sentry/vfs/lock", "//pkg/sync", "//pkg/syserror", "//pkg/usermem", diff --git a/pkg/sentry/kernel/pipe/vfs.go b/pkg/sentry/kernel/pipe/vfs.go index 2602bed72..c0e9ee1f4 100644 --- a/pkg/sentry/kernel/pipe/vfs.go +++ b/pkg/sentry/kernel/pipe/vfs.go @@ -21,6 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" @@ -61,11 +62,13 @@ func NewVFSPipe(isNamed bool, sizeBytes, atomicIOBytes int64) *VFSPipe { // // Preconditions: statusFlags should not contain an open access mode. func (vp *VFSPipe) ReaderWriterPair(mnt *vfs.Mount, vfsd *vfs.Dentry, statusFlags uint32) (*vfs.FileDescription, *vfs.FileDescription) { - return vp.newFD(mnt, vfsd, linux.O_RDONLY|statusFlags), vp.newFD(mnt, vfsd, linux.O_WRONLY|statusFlags) + // Connected pipes share the same locks. + locks := &lock.FileLocks{} + return vp.newFD(mnt, vfsd, linux.O_RDONLY|statusFlags, locks), vp.newFD(mnt, vfsd, linux.O_WRONLY|statusFlags, locks) } // Open opens the pipe represented by vp. -func (vp *VFSPipe) Open(ctx context.Context, mnt *vfs.Mount, vfsd *vfs.Dentry, statusFlags uint32) (*vfs.FileDescription, error) { +func (vp *VFSPipe) Open(ctx context.Context, mnt *vfs.Mount, vfsd *vfs.Dentry, statusFlags uint32, locks *lock.FileLocks) (*vfs.FileDescription, error) { vp.mu.Lock() defer vp.mu.Unlock() @@ -75,7 +78,7 @@ func (vp *VFSPipe) Open(ctx context.Context, mnt *vfs.Mount, vfsd *vfs.Dentry, s return nil, syserror.EINVAL } - fd := vp.newFD(mnt, vfsd, statusFlags) + fd := vp.newFD(mnt, vfsd, statusFlags, locks) // Named pipes have special blocking semantics during open: // @@ -127,10 +130,11 @@ func (vp *VFSPipe) Open(ctx context.Context, mnt *vfs.Mount, vfsd *vfs.Dentry, s } // Preconditions: vp.mu must be held. -func (vp *VFSPipe) newFD(mnt *vfs.Mount, vfsd *vfs.Dentry, statusFlags uint32) *vfs.FileDescription { +func (vp *VFSPipe) newFD(mnt *vfs.Mount, vfsd *vfs.Dentry, statusFlags uint32, locks *lock.FileLocks) *vfs.FileDescription { fd := &VFSPipeFD{ pipe: &vp.pipe, } + fd.LockFD.Init(locks) fd.vfsfd.Init(fd, statusFlags, mnt, vfsd, &vfs.FileDescriptionOptions{ DenyPRead: true, DenyPWrite: true, @@ -159,6 +163,7 @@ type VFSPipeFD struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl vfs.DentryMetadataFileDescriptionImpl + vfs.LockFD pipe *Pipe } diff --git a/pkg/sentry/socket/hostinet/BUILD b/pkg/sentry/socket/hostinet/BUILD index e82d6cd1e..60c9896fc 100644 --- a/pkg/sentry/socket/hostinet/BUILD +++ b/pkg/sentry/socket/hostinet/BUILD @@ -34,6 +34,7 @@ go_library( "//pkg/sentry/socket", "//pkg/sentry/socket/control", "//pkg/sentry/vfs", + "//pkg/sentry/vfs/lock", "//pkg/syserr", "//pkg/syserror", "//pkg/tcpip/stack", diff --git a/pkg/sentry/socket/hostinet/socket_vfs2.go b/pkg/sentry/socket/hostinet/socket_vfs2.go index 677743113..027add1fd 100644 --- a/pkg/sentry/socket/hostinet/socket_vfs2.go +++ b/pkg/sentry/socket/hostinet/socket_vfs2.go @@ -26,6 +26,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/socket" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" @@ -35,6 +36,7 @@ import ( type socketVFS2 struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl + vfs.LockFD // We store metadata for hostinet sockets internally. Technically, we should // access metadata (e.g. through stat, chmod) on the host for correctness, @@ -59,6 +61,7 @@ func newVFS2Socket(t *kernel.Task, family int, stype linux.SockType, protocol in fd: fd, }, } + s.LockFD.Init(&lock.FileLocks{}) if err := fdnotifier.AddFD(int32(fd), &s.queue); err != nil { return nil, syserr.FromError(err) } diff --git a/pkg/sentry/socket/netlink/BUILD b/pkg/sentry/socket/netlink/BUILD index 7212d8644..420e573c9 100644 --- a/pkg/sentry/socket/netlink/BUILD +++ b/pkg/sentry/socket/netlink/BUILD @@ -29,6 +29,7 @@ go_library( "//pkg/sentry/socket/unix", "//pkg/sentry/socket/unix/transport", "//pkg/sentry/vfs", + "//pkg/sentry/vfs/lock", "//pkg/sync", "//pkg/syserr", "//pkg/syserror", diff --git a/pkg/sentry/socket/netlink/socket_vfs2.go b/pkg/sentry/socket/netlink/socket_vfs2.go index b854bf990..8bfee5193 100644 --- a/pkg/sentry/socket/netlink/socket_vfs2.go +++ b/pkg/sentry/socket/netlink/socket_vfs2.go @@ -23,6 +23,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/socket/unix" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/tcpip" @@ -40,6 +41,7 @@ type SocketVFS2 struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl vfs.DentryMetadataFileDescriptionImpl + vfs.LockFD socketOpsCommon } @@ -66,7 +68,7 @@ func NewVFS2(t *kernel.Task, skType linux.SockType, protocol Protocol) (*SocketV return nil, err } - return &SocketVFS2{ + fd := &SocketVFS2{ socketOpsCommon: socketOpsCommon{ ports: t.Kernel().NetlinkPorts(), protocol: protocol, @@ -75,7 +77,9 @@ func NewVFS2(t *kernel.Task, skType linux.SockType, protocol Protocol) (*SocketV connection: connection, sendBufferSize: defaultSendBufferSize, }, - }, nil + } + fd.LockFD.Init(&lock.FileLocks{}) + return fd, nil } // Readiness implements waiter.Waitable.Readiness. diff --git a/pkg/sentry/socket/netstack/BUILD b/pkg/sentry/socket/netstack/BUILD index 8f0f5466e..0f592ecc3 100644 --- a/pkg/sentry/socket/netstack/BUILD +++ b/pkg/sentry/socket/netstack/BUILD @@ -37,6 +37,7 @@ go_library( "//pkg/sentry/socket/netfilter", "//pkg/sentry/unimpl", "//pkg/sentry/vfs", + "//pkg/sentry/vfs/lock", "//pkg/sync", "//pkg/syserr", "//pkg/syserror", diff --git a/pkg/sentry/socket/netstack/netstack_vfs2.go b/pkg/sentry/socket/netstack/netstack_vfs2.go index fcd8013c0..1412a4810 100644 --- a/pkg/sentry/socket/netstack/netstack_vfs2.go +++ b/pkg/sentry/socket/netstack/netstack_vfs2.go @@ -25,6 +25,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/socket" "gvisor.dev/gvisor/pkg/sentry/socket/netfilter" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/tcpip" @@ -38,6 +39,7 @@ type SocketVFS2 struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl vfs.DentryMetadataFileDescriptionImpl + vfs.LockFD socketOpsCommon } @@ -64,6 +66,7 @@ func NewVFS2(t *kernel.Task, family int, skType linux.SockType, protocol int, qu protocol: protocol, }, } + s.LockFD.Init(&lock.FileLocks{}) vfsfd := &s.vfsfd if err := vfsfd.Init(s, linux.O_RDWR, mnt, d, &vfs.FileDescriptionOptions{ DenyPRead: true, diff --git a/pkg/sentry/socket/unix/BUILD b/pkg/sentry/socket/unix/BUILD index de2cc4bdf..7d4cc80fe 100644 --- a/pkg/sentry/socket/unix/BUILD +++ b/pkg/sentry/socket/unix/BUILD @@ -29,6 +29,7 @@ go_library( "//pkg/sentry/socket/netstack", "//pkg/sentry/socket/unix/transport", "//pkg/sentry/vfs", + "//pkg/sentry/vfs/lock", "//pkg/syserr", "//pkg/syserror", "//pkg/tcpip", diff --git a/pkg/sentry/socket/unix/unix_vfs2.go b/pkg/sentry/socket/unix/unix_vfs2.go index 45e109361..8c32371a2 100644 --- a/pkg/sentry/socket/unix/unix_vfs2.go +++ b/pkg/sentry/socket/unix/unix_vfs2.go @@ -26,6 +26,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/socket/netstack" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/tcpip" @@ -39,6 +40,7 @@ type SocketVFS2 struct { vfsfd vfs.FileDescription vfs.FileDescriptionDefaultImpl vfs.DentryMetadataFileDescriptionImpl + vfs.LockFD socketOpsCommon } @@ -51,7 +53,7 @@ func NewSockfsFile(t *kernel.Task, ep transport.Endpoint, stype linux.SockType) mnt := t.Kernel().SocketMount() d := sockfs.NewDentry(t.Credentials(), mnt) - fd, err := NewFileDescription(ep, stype, linux.O_RDWR, mnt, d) + fd, err := NewFileDescription(ep, stype, linux.O_RDWR, mnt, d, &lock.FileLocks{}) if err != nil { return nil, syserr.FromError(err) } @@ -60,7 +62,7 @@ func NewSockfsFile(t *kernel.Task, ep transport.Endpoint, stype linux.SockType) // NewFileDescription creates and returns a socket file description // corresponding to the given mount and dentry. -func NewFileDescription(ep transport.Endpoint, stype linux.SockType, flags uint32, mnt *vfs.Mount, d *vfs.Dentry) (*vfs.FileDescription, error) { +func NewFileDescription(ep transport.Endpoint, stype linux.SockType, flags uint32, mnt *vfs.Mount, d *vfs.Dentry, locks *lock.FileLocks) (*vfs.FileDescription, error) { // You can create AF_UNIX, SOCK_RAW sockets. They're the same as // SOCK_DGRAM and don't require CAP_NET_RAW. if stype == linux.SOCK_RAW { @@ -73,6 +75,7 @@ func NewFileDescription(ep transport.Endpoint, stype linux.SockType, flags uint3 stype: stype, }, } + sock.LockFD.Init(locks) vfsfd := &sock.vfsfd if err := vfsfd.Init(sock, flags, mnt, d, &vfs.FileDescriptionOptions{ DenyPRead: true, diff --git a/pkg/sentry/syscalls/linux/sys_file.go b/pkg/sentry/syscalls/linux/sys_file.go index 35a98212a..8347617bd 100644 --- a/pkg/sentry/syscalls/linux/sys_file.go +++ b/pkg/sentry/syscalls/linux/sys_file.go @@ -998,9 +998,6 @@ func Fcntl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall return 0, nil, err } - // The lock uid is that of the Task's FDTable. - lockUniqueID := lock.UniqueID(t.FDTable().ID()) - // These locks don't block; execute the non-blocking operation using the inode's lock // context directly. switch flock.Type { @@ -1010,12 +1007,12 @@ func Fcntl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall } if cmd == linux.F_SETLK { // Non-blocking lock, provide a nil lock.Blocker. - if !file.Dirent.Inode.LockCtx.Posix.LockRegion(lockUniqueID, lock.ReadLock, rng, nil) { + if !file.Dirent.Inode.LockCtx.Posix.LockRegion(t.FDTable(), lock.ReadLock, rng, nil) { return 0, nil, syserror.EAGAIN } } else { // Blocking lock, pass in the task to satisfy the lock.Blocker interface. - if !file.Dirent.Inode.LockCtx.Posix.LockRegion(lockUniqueID, lock.ReadLock, rng, t) { + if !file.Dirent.Inode.LockCtx.Posix.LockRegion(t.FDTable(), lock.ReadLock, rng, t) { return 0, nil, syserror.EINTR } } @@ -1026,18 +1023,18 @@ func Fcntl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall } if cmd == linux.F_SETLK { // Non-blocking lock, provide a nil lock.Blocker. - if !file.Dirent.Inode.LockCtx.Posix.LockRegion(lockUniqueID, lock.WriteLock, rng, nil) { + if !file.Dirent.Inode.LockCtx.Posix.LockRegion(t.FDTable(), lock.WriteLock, rng, nil) { return 0, nil, syserror.EAGAIN } } else { // Blocking lock, pass in the task to satisfy the lock.Blocker interface. - if !file.Dirent.Inode.LockCtx.Posix.LockRegion(lockUniqueID, lock.WriteLock, rng, t) { + if !file.Dirent.Inode.LockCtx.Posix.LockRegion(t.FDTable(), lock.WriteLock, rng, t) { return 0, nil, syserror.EINTR } } return 0, nil, nil case linux.F_UNLCK: - file.Dirent.Inode.LockCtx.Posix.UnlockRegion(lockUniqueID, rng) + file.Dirent.Inode.LockCtx.Posix.UnlockRegion(t.FDTable(), rng) return 0, nil, nil default: return 0, nil, syserror.EINVAL @@ -2157,22 +2154,6 @@ func Flock(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall nonblocking := operation&linux.LOCK_NB != 0 operation &^= linux.LOCK_NB - // flock(2): - // Locks created by flock() are associated with an open file table entry. This means that - // duplicate file descriptors (created by, for example, fork(2) or dup(2)) refer to the - // same lock, and this lock may be modified or released using any of these descriptors. Furthermore, - // the lock is released either by an explicit LOCK_UN operation on any of these duplicate - // descriptors, or when all such descriptors have been closed. - // - // If a process uses open(2) (or similar) to obtain more than one descriptor for the same file, - // these descriptors are treated independently by flock(). An attempt to lock the file using - // one of these file descriptors may be denied by a lock that the calling process has already placed via - // another descriptor. - // - // We use the File UniqueID as the lock UniqueID because it needs to reference the same lock across dup(2) - // and fork(2). - lockUniqueID := lock.UniqueID(file.UniqueID) - // A BSD style lock spans the entire file. rng := lock.LockRange{ Start: 0, @@ -2183,29 +2164,29 @@ func Flock(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall case linux.LOCK_EX: if nonblocking { // Since we're nonblocking we pass a nil lock.Blocker implementation. - if !file.Dirent.Inode.LockCtx.BSD.LockRegion(lockUniqueID, lock.WriteLock, rng, nil) { + if !file.Dirent.Inode.LockCtx.BSD.LockRegion(file, lock.WriteLock, rng, nil) { return 0, nil, syserror.EWOULDBLOCK } } else { // Because we're blocking we will pass the task to satisfy the lock.Blocker interface. - if !file.Dirent.Inode.LockCtx.BSD.LockRegion(lockUniqueID, lock.WriteLock, rng, t) { + if !file.Dirent.Inode.LockCtx.BSD.LockRegion(file, lock.WriteLock, rng, t) { return 0, nil, syserror.EINTR } } case linux.LOCK_SH: if nonblocking { // Since we're nonblocking we pass a nil lock.Blocker implementation. - if !file.Dirent.Inode.LockCtx.BSD.LockRegion(lockUniqueID, lock.ReadLock, rng, nil) { + if !file.Dirent.Inode.LockCtx.BSD.LockRegion(file, lock.ReadLock, rng, nil) { return 0, nil, syserror.EWOULDBLOCK } } else { // Because we're blocking we will pass the task to satisfy the lock.Blocker interface. - if !file.Dirent.Inode.LockCtx.BSD.LockRegion(lockUniqueID, lock.ReadLock, rng, t) { + if !file.Dirent.Inode.LockCtx.BSD.LockRegion(file, lock.ReadLock, rng, t) { return 0, nil, syserror.EINTR } } case linux.LOCK_UN: - file.Dirent.Inode.LockCtx.BSD.UnlockRegion(lockUniqueID, rng) + file.Dirent.Inode.LockCtx.BSD.UnlockRegion(file, rng) default: // flock(2): EINVAL operation is invalid. return 0, nil, syserror.EINVAL diff --git a/pkg/sentry/syscalls/linux/vfs2/BUILD b/pkg/sentry/syscalls/linux/vfs2/BUILD index c0d005247..9f93f4354 100644 --- a/pkg/sentry/syscalls/linux/vfs2/BUILD +++ b/pkg/sentry/syscalls/linux/vfs2/BUILD @@ -14,6 +14,7 @@ go_library( "getdents.go", "inotify.go", "ioctl.go", + "lock.go", "memfd.go", "mmap.go", "mount.go", @@ -42,6 +43,7 @@ go_library( "//pkg/fspath", "//pkg/gohacks", "//pkg/sentry/arch", + "//pkg/sentry/fs/lock", "//pkg/sentry/fsbridge", "//pkg/sentry/fsimpl/eventfd", "//pkg/sentry/fsimpl/pipefs", diff --git a/pkg/sentry/syscalls/linux/vfs2/lock.go b/pkg/sentry/syscalls/linux/vfs2/lock.go new file mode 100644 index 000000000..bf19028c4 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/lock.go @@ -0,0 +1,64 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/fs/lock" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/syserror" +) + +// Flock implements linux syscall flock(2). +func Flock(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + operation := args[1].Int() + + file := t.GetFileVFS2(fd) + if file == nil { + // flock(2): EBADF fd is not an open file descriptor. + return 0, nil, syserror.EBADF + } + defer file.DecRef() + + nonblocking := operation&linux.LOCK_NB != 0 + operation &^= linux.LOCK_NB + + var blocker lock.Blocker + if !nonblocking { + blocker = t + } + + switch operation { + case linux.LOCK_EX: + if err := file.LockBSD(t, lock.WriteLock, blocker); err != nil { + return 0, nil, err + } + case linux.LOCK_SH: + if err := file.LockBSD(t, lock.ReadLock, blocker); err != nil { + return 0, nil, err + } + case linux.LOCK_UN: + if err := file.UnlockBSD(t); err != nil { + return 0, nil, err + } + default: + // flock(2): EINVAL operation is invalid. + return 0, nil, syserror.EINVAL + } + + return 0, nil, nil +} diff --git a/pkg/sentry/syscalls/linux/vfs2/vfs2.go b/pkg/sentry/syscalls/linux/vfs2/vfs2.go index 7b6e7571a..954c82f97 100644 --- a/pkg/sentry/syscalls/linux/vfs2/vfs2.go +++ b/pkg/sentry/syscalls/linux/vfs2/vfs2.go @@ -62,7 +62,7 @@ func Override() { s.Table[55] = syscalls.Supported("getsockopt", GetSockOpt) s.Table[59] = syscalls.Supported("execve", Execve) s.Table[72] = syscalls.Supported("fcntl", Fcntl) - delete(s.Table, 73) // flock + s.Table[73] = syscalls.Supported("fcntl", Flock) s.Table[74] = syscalls.Supported("fsync", Fsync) s.Table[75] = syscalls.Supported("fdatasync", Fdatasync) s.Table[76] = syscalls.Supported("truncate", Truncate) diff --git a/pkg/sentry/vfs/BUILD b/pkg/sentry/vfs/BUILD index 774cc66cc..16d9f3a28 100644 --- a/pkg/sentry/vfs/BUILD +++ b/pkg/sentry/vfs/BUILD @@ -72,6 +72,7 @@ go_library( "//pkg/sentry/memmap", "//pkg/sentry/socket/unix/transport", "//pkg/sentry/uniqueid", + "//pkg/sentry/vfs/lock", "//pkg/sync", "//pkg/syserror", "//pkg/usermem", diff --git a/pkg/sentry/vfs/epoll.go b/pkg/sentry/vfs/epoll.go index 8297f964b..599c3131c 100644 --- a/pkg/sentry/vfs/epoll.go +++ b/pkg/sentry/vfs/epoll.go @@ -31,6 +31,7 @@ type EpollInstance struct { vfsfd FileDescription FileDescriptionDefaultImpl DentryMetadataFileDescriptionImpl + NoLockFD // q holds waiters on this EpollInstance. q waiter.Queue diff --git a/pkg/sentry/vfs/file_description.go b/pkg/sentry/vfs/file_description.go index bb294563d..97b9b18d7 100644 --- a/pkg/sentry/vfs/file_description.go +++ b/pkg/sentry/vfs/file_description.go @@ -73,6 +73,8 @@ type FileDescription struct { // writable is analogous to Linux's FMODE_WRITE. writable bool + usedLockBSD uint32 + // impl is the FileDescriptionImpl associated with this Filesystem. impl is // immutable. This should be the last field in FileDescription. impl FileDescriptionImpl @@ -175,6 +177,12 @@ func (fd *FileDescription) DecRef() { } ep.interestMu.Unlock() } + + // If BSD locks were used, release any lock that it may have acquired. + if atomic.LoadUint32(&fd.usedLockBSD) != 0 { + fd.impl.UnlockBSD(context.Background(), fd) + } + // Release implementation resources. fd.impl.Release() if fd.writable { @@ -420,13 +428,9 @@ type FileDescriptionImpl interface { Removexattr(ctx context.Context, name string) error // LockBSD tries to acquire a BSD-style advisory file lock. - // - // TODO(gvisor.dev/issue/1480): BSD-style file locking LockBSD(ctx context.Context, uid lock.UniqueID, t lock.LockType, block lock.Blocker) error - // LockBSD releases a BSD-style advisory file lock. - // - // TODO(gvisor.dev/issue/1480): BSD-style file locking + // UnlockBSD releases a BSD-style advisory file lock. UnlockBSD(ctx context.Context, uid lock.UniqueID) error // LockPOSIX tries to acquire a POSIX-style advisory file lock. @@ -736,3 +740,14 @@ func (fd *FileDescription) InodeID() uint64 { func (fd *FileDescription) Msync(ctx context.Context, mr memmap.MappableRange) error { return fd.Sync(ctx) } + +// LockBSD tries to acquire a BSD-style advisory file lock. +func (fd *FileDescription) LockBSD(ctx context.Context, lockType lock.LockType, blocker lock.Blocker) error { + atomic.StoreUint32(&fd.usedLockBSD, 1) + return fd.impl.LockBSD(ctx, fd, lockType, blocker) +} + +// UnlockBSD releases a BSD-style advisory file lock. +func (fd *FileDescription) UnlockBSD(ctx context.Context) error { + return fd.impl.UnlockBSD(ctx, fd) +} diff --git a/pkg/sentry/vfs/file_description_impl_util.go b/pkg/sentry/vfs/file_description_impl_util.go index f4c111926..af7213dfd 100644 --- a/pkg/sentry/vfs/file_description_impl_util.go +++ b/pkg/sentry/vfs/file_description_impl_util.go @@ -21,8 +21,9 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/fs/lock" + fslock "gvisor.dev/gvisor/pkg/sentry/fs/lock" "gvisor.dev/gvisor/pkg/sentry/memmap" + "gvisor.dev/gvisor/pkg/sentry/vfs/lock" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" @@ -153,26 +154,6 @@ func (FileDescriptionDefaultImpl) Removexattr(ctx context.Context, name string) return syserror.ENOTSUP } -// LockBSD implements FileDescriptionImpl.LockBSD. -func (FileDescriptionDefaultImpl) LockBSD(ctx context.Context, uid lock.UniqueID, t lock.LockType, block lock.Blocker) error { - return syserror.EBADF -} - -// UnlockBSD implements FileDescriptionImpl.UnlockBSD. -func (FileDescriptionDefaultImpl) UnlockBSD(ctx context.Context, uid lock.UniqueID) error { - return syserror.EBADF -} - -// LockPOSIX implements FileDescriptionImpl.LockPOSIX. -func (FileDescriptionDefaultImpl) LockPOSIX(ctx context.Context, uid lock.UniqueID, t lock.LockType, rng lock.LockRange, block lock.Blocker) error { - return syserror.EBADF -} - -// UnlockPOSIX implements FileDescriptionImpl.UnlockPOSIX. -func (FileDescriptionDefaultImpl) UnlockPOSIX(ctx context.Context, uid lock.UniqueID, rng lock.LockRange) error { - return syserror.EBADF -} - // DirectoryFileDescriptionDefaultImpl may be embedded by implementations of // FileDescriptionImpl that always represent directories to obtain // implementations of non-directory I/O methods that return EISDIR. @@ -384,3 +365,60 @@ func GenericConfigureMMap(fd *FileDescription, m memmap.Mappable, opts *memmap.M fd.IncRef() return nil } + +// LockFD may be used by most implementations of FileDescriptionImpl.Lock* +// functions. Caller must call Init(). +type LockFD struct { + locks *lock.FileLocks +} + +// Init initializes fd with FileLocks to use. +func (fd *LockFD) Init(locks *lock.FileLocks) { + fd.locks = locks +} + +// LockBSD implements vfs.FileDescriptionImpl.LockBSD. +func (fd *LockFD) LockBSD(ctx context.Context, uid fslock.UniqueID, t fslock.LockType, block fslock.Blocker) error { + return fd.locks.LockBSD(uid, t, block) +} + +// UnlockBSD implements vfs.FileDescriptionImpl.UnlockBSD. +func (fd *LockFD) UnlockBSD(ctx context.Context, uid fslock.UniqueID) error { + fd.locks.UnlockBSD(uid) + return nil +} + +// LockPOSIX implements vfs.FileDescriptionImpl.LockPOSIX. +func (fd *LockFD) LockPOSIX(ctx context.Context, uid fslock.UniqueID, t fslock.LockType, rng fslock.LockRange, block fslock.Blocker) error { + return fd.locks.LockPOSIX(uid, t, rng, block) +} + +// UnlockPOSIX implements vfs.FileDescriptionImpl.UnlockPOSIX. +func (fd *LockFD) UnlockPOSIX(ctx context.Context, uid fslock.UniqueID, rng fslock.LockRange) error { + fd.locks.UnlockPOSIX(uid, rng) + return nil +} + +// NoLockFD implements Lock*/Unlock* portion of FileDescriptionImpl interface +// returning ENOLCK. +type NoLockFD struct{} + +// LockBSD implements vfs.FileDescriptionImpl.LockBSD. +func (NoLockFD) LockBSD(ctx context.Context, uid fslock.UniqueID, t fslock.LockType, block fslock.Blocker) error { + return syserror.ENOLCK +} + +// UnlockBSD implements vfs.FileDescriptionImpl.UnlockBSD. +func (NoLockFD) UnlockBSD(ctx context.Context, uid fslock.UniqueID) error { + return syserror.ENOLCK +} + +// LockPOSIX implements vfs.FileDescriptionImpl.LockPOSIX. +func (NoLockFD) LockPOSIX(ctx context.Context, uid fslock.UniqueID, t fslock.LockType, rng fslock.LockRange, block fslock.Blocker) error { + return syserror.ENOLCK +} + +// UnlockPOSIX implements vfs.FileDescriptionImpl.UnlockPOSIX. +func (NoLockFD) UnlockPOSIX(ctx context.Context, uid fslock.UniqueID, rng fslock.LockRange) error { + return syserror.ENOLCK +} diff --git a/pkg/sentry/vfs/file_description_impl_util_test.go b/pkg/sentry/vfs/file_description_impl_util_test.go index 3a75d4d62..5061f6ac9 100644 --- a/pkg/sentry/vfs/file_description_impl_util_test.go +++ b/pkg/sentry/vfs/file_description_impl_util_test.go @@ -33,6 +33,7 @@ import ( type fileDescription struct { vfsfd FileDescription FileDescriptionDefaultImpl + NoLockFD } // genCount contains the number of times its DynamicBytesSource.Generate() diff --git a/pkg/sentry/vfs/inotify.go b/pkg/sentry/vfs/inotify.go index 05a3051a4..7fa7d2d0c 100644 --- a/pkg/sentry/vfs/inotify.go +++ b/pkg/sentry/vfs/inotify.go @@ -57,6 +57,7 @@ type Inotify struct { vfsfd FileDescription FileDescriptionDefaultImpl DentryMetadataFileDescriptionImpl + NoLockFD // Unique identifier for this inotify instance. We don't just reuse the // inotify fd because fds can be duped. These should not be exposed to the |