diff options
Diffstat (limited to 'pkg/sentry')
| -rw-r--r-- | pkg/sentry/kernel/auth/BUILD | 12 | ||||
| -rw-r--r-- | pkg/sentry/kernel/task.go | 11 | ||||
| -rw-r--r-- | pkg/sentry/kernel/task_clone.go | 9 | ||||
| -rw-r--r-- | pkg/sentry/kernel/task_identity.go | 220 | ||||
| -rw-r--r-- | pkg/sentry/kernel/task_start.go | 2 |
5 files changed, 143 insertions, 111 deletions
diff --git a/pkg/sentry/kernel/auth/BUILD b/pkg/sentry/kernel/auth/BUILD index 37cb8c8b9..42779baa9 100644 --- a/pkg/sentry/kernel/auth/BUILD +++ b/pkg/sentry/kernel/auth/BUILD @@ -4,6 +4,17 @@ load("//tools/go_generics:defs.bzl", "go_template_instance") load("//tools/go_stateify:defs.bzl", "go_library") go_template_instance( + name = "atomicptr_credentials", + out = "atomicptr_credentials.go", + package = "auth", + suffix = "Credentials", + template = "//third_party/gvsync:generic_atomicptr", + types = { + "Value": "Credentials", + }, +) + +go_template_instance( name = "id_map_range", out = "id_map_range.go", package = "auth", @@ -34,6 +45,7 @@ go_template_instance( go_library( name = "auth", srcs = [ + "atomicptr_credentials.go", "auth.go", "capability_set.go", "context.go", diff --git a/pkg/sentry/kernel/task.go b/pkg/sentry/kernel/task.go index c297c5973..2e3a39d3b 100644 --- a/pkg/sentry/kernel/task.go +++ b/pkg/sentry/kernel/task.go @@ -386,10 +386,11 @@ type Task struct { // creds is the task's credentials. // - // creds is protected by mu, however the value itself is immutable and can - // only be changed by a copy. After reading the pointer, access will - // proceed outside the scope of mu. creds is owned by the task goroutine. - creds *auth.Credentials + // creds.Load() may be called without synchronization. creds.Store() is + // serialized by mu. creds is owned by the task goroutine. All + // auth.Credentials objects that creds may point to, or have pointed to + // in the past, must be treated as immutable. + creds auth.AtomicPtrCredentials // utsns is the task's UTS namespace. // @@ -597,7 +598,7 @@ func (t *Task) Value(key interface{}) interface{} { case CtxTask: return t case auth.CtxCredentials: - return t.creds + return t.Credentials() case context.CtxThreadGroupID: return int32(t.ThreadGroup().ID()) case fs.CtxRoot: diff --git a/pkg/sentry/kernel/task_clone.go b/pkg/sentry/kernel/task_clone.go index 0e621f0d1..b5cc3860d 100644 --- a/pkg/sentry/kernel/task_clone.go +++ b/pkg/sentry/kernel/task_clone.go @@ -425,6 +425,7 @@ func (t *Task) Unshare(opts *SharingOptions) error { if opts.NewAddressSpace || opts.NewSignalHandlers { return syserror.EINVAL } + creds := t.Credentials() if opts.NewThreadGroup { t.tg.signalHandlers.mu.Lock() if t.tg.tasksCount != 1 { @@ -439,8 +440,6 @@ func (t *Task) Unshare(opts *SharingOptions) error { if t.IsChrooted() { return syserror.EPERM } - // This temporary is needed because Go. - creds := t.Credentials() newUserNS, err := creds.NewChildUserNamespace() if err != nil { return err @@ -449,6 +448,8 @@ func (t *Task) Unshare(opts *SharingOptions) error { if err != nil { return err } + // Need to reload creds, becaue t.SetUserNamespace() changed task credentials. + creds = t.Credentials() } haveCapSysAdmin := t.HasCapability(linux.CAP_SYS_ADMIN) if opts.NewPIDNamespace { @@ -473,7 +474,7 @@ func (t *Task) Unshare(opts *SharingOptions) error { } // Note that this must happen after NewUserNamespace, so the // new user namespace is used if there is one. - t.utsns = t.utsns.Clone(t.creds.UserNamespace) + t.utsns = t.utsns.Clone(creds.UserNamespace) } if opts.NewIPCNamespace { if !haveCapSysAdmin { @@ -482,7 +483,7 @@ func (t *Task) Unshare(opts *SharingOptions) error { } // Note that "If CLONE_NEWIPC is set, then create the process in a new IPC // namespace" - t.ipcns = NewIPCNamespace(t.creds.UserNamespace) + t.ipcns = NewIPCNamespace(creds.UserNamespace) } var oldfds *FDMap if opts.NewFiles { diff --git a/pkg/sentry/kernel/task_identity.go b/pkg/sentry/kernel/task_identity.go index 39c138925..78ff14b20 100644 --- a/pkg/sentry/kernel/task_identity.go +++ b/pkg/sentry/kernel/task_identity.go @@ -25,30 +25,22 @@ import ( // // This value must be considered immutable. func (t *Task) Credentials() *auth.Credentials { - t.mu.Lock() - defer t.mu.Unlock() - return t.creds + return t.creds.Load() } // UserNamespace returns the user namespace associated with the task. func (t *Task) UserNamespace() *auth.UserNamespace { - t.mu.Lock() - defer t.mu.Unlock() - return t.creds.UserNamespace + return t.Credentials().UserNamespace } // HasCapabilityIn checks if the task has capability cp in user namespace ns. func (t *Task) HasCapabilityIn(cp linux.Capability, ns *auth.UserNamespace) bool { - t.mu.Lock() - defer t.mu.Unlock() - return t.creds.HasCapabilityIn(cp, ns) + return t.Credentials().HasCapabilityIn(cp, ns) } // HasCapability checks if the task has capability cp in its user namespace. func (t *Task) HasCapability(cp linux.Capability) bool { - t.mu.Lock() - defer t.mu.Unlock() - return t.creds.HasCapability(cp) + return t.Credentials().HasCapability(cp) } // SetUID implements the semantics of setuid(2). @@ -57,9 +49,12 @@ func (t *Task) SetUID(uid auth.UID) error { if !uid.Ok() { return syserror.EINVAL } + t.mu.Lock() defer t.mu.Unlock() - kuid := t.creds.UserNamespace.MapToKUID(uid) + + creds := t.Credentials() + kuid := creds.UserNamespace.MapToKUID(uid) if !kuid.Ok() { return syserror.EINVAL } @@ -67,17 +62,17 @@ func (t *Task) SetUID(uid auth.UID) error { // effective UID of the caller is root (more precisely: if the caller has // the CAP_SETUID capability), the real UID and saved set-user-ID are also // set." - setuid(2) - if t.creds.HasCapability(linux.CAP_SETUID) { + if creds.HasCapability(linux.CAP_SETUID) { t.setKUIDsUncheckedLocked(kuid, kuid, kuid) return nil } // "EPERM: The user is not privileged (Linux: does not have the CAP_SETUID // capability) and uid does not match the real UID or saved set-user-ID of // the calling process." - if kuid != t.creds.RealKUID && kuid != t.creds.SavedKUID { + if kuid != creds.RealKUID && kuid != creds.SavedKUID { return syserror.EPERM } - t.setKUIDsUncheckedLocked(t.creds.RealKUID, kuid, t.creds.SavedKUID) + t.setKUIDsUncheckedLocked(creds.RealKUID, kuid, creds.SavedKUID) return nil } @@ -87,37 +82,38 @@ func (t *Task) SetREUID(r, e auth.UID) error { defer t.mu.Unlock() // "Supplying a value of -1 for either the real or effective user ID forces // the system to leave that ID unchanged." - setreuid(2) - newR := t.creds.RealKUID + creds := t.Credentials() + newR := creds.RealKUID if r.Ok() { - newR = t.creds.UserNamespace.MapToKUID(r) + newR = creds.UserNamespace.MapToKUID(r) if !newR.Ok() { return syserror.EINVAL } } - newE := t.creds.EffectiveKUID + newE := creds.EffectiveKUID if e.Ok() { - newE = t.creds.UserNamespace.MapToKUID(e) + newE = creds.UserNamespace.MapToKUID(e) if !newE.Ok() { return syserror.EINVAL } } - if !t.creds.HasCapability(linux.CAP_SETUID) { + if !creds.HasCapability(linux.CAP_SETUID) { // "Unprivileged processes may only set the effective user ID to the // real user ID, the effective user ID, or the saved set-user-ID." - if newE != t.creds.RealKUID && newE != t.creds.EffectiveKUID && newE != t.creds.SavedKUID { + if newE != creds.RealKUID && newE != creds.EffectiveKUID && newE != creds.SavedKUID { return syserror.EPERM } // "Unprivileged users may only set the real user ID to the real user // ID or the effective user ID." - if newR != t.creds.RealKUID && newR != t.creds.EffectiveKUID { + if newR != creds.RealKUID && newR != creds.EffectiveKUID { return syserror.EPERM } } // "If the real user ID is set (i.e., ruid is not -1) or the effective user // ID is set to a value not equal to the previous real user ID, the saved // set-user-ID will be set to the new effective user ID." - newS := t.creds.SavedKUID - if r.Ok() || (e.Ok() && newE != t.creds.EffectiveKUID) { + newS := creds.SavedKUID + if r.Ok() || (e.Ok() && newE != creds.EffectiveKUID) { newS = newE } t.setKUIDsUncheckedLocked(newR, newE, newS) @@ -136,23 +132,24 @@ func (t *Task) SetRESUID(r, e, s auth.UID) error { // arguments equals -1, the corresponding value is not changed." - // setresuid(2) var err error - newR := t.creds.RealKUID + creds := t.Credentials() + newR := creds.RealKUID if r.Ok() { - newR, err = t.creds.UseUID(r) + newR, err = creds.UseUID(r) if err != nil { return err } } - newE := t.creds.EffectiveKUID + newE := creds.EffectiveKUID if e.Ok() { - newE, err = t.creds.UseUID(e) + newE, err = creds.UseUID(e) if err != nil { return err } } - newS := t.creds.SavedKUID + newS := creds.SavedKUID if s.Ok() { - newS, err = t.creds.UseUID(s) + newS, err = creds.UseUID(s) if err != nil { return err } @@ -163,10 +160,10 @@ func (t *Task) SetRESUID(r, e, s auth.UID) error { // Preconditions: t.mu must be locked. func (t *Task) setKUIDsUncheckedLocked(newR, newE, newS auth.KUID) { - root := t.creds.UserNamespace.MapToKUID(auth.RootUID) - oldR, oldE, oldS := t.creds.RealKUID, t.creds.EffectiveKUID, t.creds.SavedKUID - t.creds = t.creds.Fork() // See doc for creds. - t.creds.RealKUID, t.creds.EffectiveKUID, t.creds.SavedKUID = newR, newE, newS + creds := t.Credentials().Fork() // The credentials object is immutable. See doc for creds. + root := creds.UserNamespace.MapToKUID(auth.RootUID) + oldR, oldE, oldS := creds.RealKUID, creds.EffectiveKUID, creds.SavedKUID + creds.RealKUID, creds.EffectiveKUID, creds.SavedKUID = newR, newE, newS // "1. If one or more of the real, effective or saved set user IDs was // previously 0, and as a result of the UID changes all of these IDs have a @@ -184,9 +181,9 @@ func (t *Task) setKUIDsUncheckedLocked(newR, newE, newS auth.KUID) { // being cleared." (A thread's effective capability set is always // cleared when such a credential change is made, // regardless of the setting of the "keep capabilities" flag.) - if !t.creds.KeepCaps { - t.creds.PermittedCaps = 0 - t.creds.EffectiveCaps = 0 + if !creds.KeepCaps { + creds.PermittedCaps = 0 + creds.EffectiveCaps = 0 } } // """ @@ -197,9 +194,9 @@ func (t *Task) setKUIDsUncheckedLocked(newR, newE, newS auth.KUID) { // permitted set is copied to the effective set. // """ if oldE == root && newE != root { - t.creds.EffectiveCaps = 0 + creds.EffectiveCaps = 0 } else if oldE != root && newE == root { - t.creds.EffectiveCaps = t.creds.PermittedCaps + creds.EffectiveCaps = creds.PermittedCaps } // "4. If the filesystem user ID is changed from 0 to nonzero (see // setfsuid(2)), then the following capabilities are cleared from the @@ -220,6 +217,7 @@ func (t *Task) setKUIDsUncheckedLocked(newR, newE, newS auth.KUID) { // Not documented, but compare Linux's kernel/cred.c:commit_creds(). t.parentDeathSignal = 0 } + t.creds.Store(creds) } // SetGID implements the semantics of setgid(2). @@ -227,20 +225,23 @@ func (t *Task) SetGID(gid auth.GID) error { if !gid.Ok() { return syserror.EINVAL } + t.mu.Lock() defer t.mu.Unlock() - kgid := t.creds.UserNamespace.MapToKGID(gid) + + creds := t.Credentials() + kgid := creds.UserNamespace.MapToKGID(gid) if !kgid.Ok() { return syserror.EINVAL } - if t.creds.HasCapability(linux.CAP_SETGID) { + if creds.HasCapability(linux.CAP_SETGID) { t.setKGIDsUncheckedLocked(kgid, kgid, kgid) return nil } - if kgid != t.creds.RealKGID && kgid != t.creds.SavedKGID { + if kgid != creds.RealKGID && kgid != creds.SavedKGID { return syserror.EPERM } - t.setKGIDsUncheckedLocked(t.creds.RealKGID, kgid, t.creds.SavedKGID) + t.setKGIDsUncheckedLocked(creds.RealKGID, kgid, creds.SavedKGID) return nil } @@ -248,30 +249,32 @@ func (t *Task) SetGID(gid auth.GID) error { func (t *Task) SetREGID(r, e auth.GID) error { t.mu.Lock() defer t.mu.Unlock() - newR := t.creds.RealKGID + + creds := t.Credentials() + newR := creds.RealKGID if r.Ok() { - newR = t.creds.UserNamespace.MapToKGID(r) + newR = creds.UserNamespace.MapToKGID(r) if !newR.Ok() { return syserror.EINVAL } } - newE := t.creds.EffectiveKGID + newE := creds.EffectiveKGID if e.Ok() { - newE = t.creds.UserNamespace.MapToKGID(e) + newE = creds.UserNamespace.MapToKGID(e) if !newE.Ok() { return syserror.EINVAL } } - if !t.creds.HasCapability(linux.CAP_SETGID) { - if newE != t.creds.RealKGID && newE != t.creds.EffectiveKGID && newE != t.creds.SavedKGID { + if !creds.HasCapability(linux.CAP_SETGID) { + if newE != creds.RealKGID && newE != creds.EffectiveKGID && newE != creds.SavedKGID { return syserror.EPERM } - if newR != t.creds.RealKGID && newR != t.creds.EffectiveKGID { + if newR != creds.RealKGID && newR != creds.EffectiveKGID { return syserror.EPERM } } - newS := t.creds.SavedKGID - if r.Ok() || (e.Ok() && newE != t.creds.EffectiveKGID) { + newS := creds.SavedKGID + if r.Ok() || (e.Ok() && newE != creds.EffectiveKGID) { newS = newE } t.setKGIDsUncheckedLocked(newR, newE, newS) @@ -280,26 +283,29 @@ func (t *Task) SetREGID(r, e auth.GID) error { // SetRESGID implements the semantics of the setresgid(2) syscall. func (t *Task) SetRESGID(r, e, s auth.GID) error { + var err error + t.mu.Lock() defer t.mu.Unlock() - var err error - newR := t.creds.RealKGID + + creds := t.Credentials() + newR := creds.RealKGID if r.Ok() { - newR, err = t.creds.UseGID(r) + newR, err = creds.UseGID(r) if err != nil { return err } } - newE := t.creds.EffectiveKGID + newE := creds.EffectiveKGID if e.Ok() { - newE, err = t.creds.UseGID(e) + newE, err = creds.UseGID(e) if err != nil { return err } } - newS := t.creds.SavedKGID + newS := creds.SavedKGID if s.Ok() { - newS, err = t.creds.UseGID(s) + newS, err = creds.UseGID(s) if err != nil { return err } @@ -309,9 +315,9 @@ func (t *Task) SetRESGID(r, e, s auth.GID) error { } func (t *Task) setKGIDsUncheckedLocked(newR, newE, newS auth.KGID) { - oldE := t.creds.EffectiveKGID - t.creds = t.creds.Fork() // See doc for creds. - t.creds.RealKGID, t.creds.EffectiveKGID, t.creds.SavedKGID = newR, newE, newS + creds := t.Credentials().Fork() // The credentials object is immutable. See doc for creds. + oldE := creds.EffectiveKGID + creds.RealKGID, creds.EffectiveKGID, creds.SavedKGID = newR, newE, newS if oldE != newE { // "[dumpability] is reset to the current value contained in @@ -327,6 +333,7 @@ func (t *Task) setKGIDsUncheckedLocked(newR, newE, newS auth.KGID) { // kernel/cred.c:commit_creds(). t.parentDeathSignal = 0 } + t.creds.Store(creds) } // SetExtraGIDs attempts to change t's supplemental groups. All IDs are @@ -334,19 +341,21 @@ func (t *Task) setKGIDsUncheckedLocked(newR, newE, newS auth.KGID) { func (t *Task) SetExtraGIDs(gids []auth.GID) error { t.mu.Lock() defer t.mu.Unlock() - if !t.creds.HasCapability(linux.CAP_SETGID) { + creds := t.Credentials() + if !creds.HasCapability(linux.CAP_SETGID) { return syserror.EPERM } kgids := make([]auth.KGID, len(gids)) for i, gid := range gids { - kgid := t.creds.UserNamespace.MapToKGID(gid) + kgid := creds.UserNamespace.MapToKGID(gid) if !kgid.Ok() { return syserror.EINVAL } kgids[i] = kgid } - t.creds = t.creds.Fork() // See doc for creds. - t.creds.ExtraKGIDs = kgids + creds = creds.Fork() // The credentials object is immutable. See doc for creds. + creds.ExtraKGIDs = kgids + t.creds.Store(creds) return nil } @@ -360,27 +369,29 @@ func (t *Task) SetCapabilitySets(permitted, inheritable, effective auth.Capabili if effective & ^permitted != 0 { return syserror.EPERM } + creds := t.Credentials() // "It is also a limiting superset for the capabilities that may be added // to the inheritable set by a thread that does not have the CAP_SETPCAP // capability in its effective set." - if !t.creds.HasCapability(linux.CAP_SETPCAP) && (inheritable & ^(t.creds.InheritableCaps|t.creds.PermittedCaps) != 0) { + if !creds.HasCapability(linux.CAP_SETPCAP) && (inheritable & ^(creds.InheritableCaps|creds.PermittedCaps) != 0) { return syserror.EPERM } // "If a thread drops a capability from its permitted set, it can never // reacquire that capability (unless it execve(2)s ..." - if permitted & ^t.creds.PermittedCaps != 0 { + if permitted & ^creds.PermittedCaps != 0 { return syserror.EPERM } // "... if a capability is not in the bounding set, then a thread can't add // this capability to its inheritable set, even if it was in its permitted // capabilities ..." - if inheritable & ^(t.creds.InheritableCaps|t.creds.BoundingCaps) != 0 { + if inheritable & ^(creds.InheritableCaps|creds.BoundingCaps) != 0 { return syserror.EPERM } - t.creds = t.creds.Fork() // See doc for creds. - t.creds.PermittedCaps = permitted - t.creds.InheritableCaps = inheritable - t.creds.EffectiveCaps = effective + creds = creds.Fork() // The credentials object is immutable. See doc for creds. + creds.PermittedCaps = permitted + creds.InheritableCaps = inheritable + creds.EffectiveCaps = effective + t.creds.Store(creds) return nil } @@ -389,11 +400,13 @@ func (t *Task) SetCapabilitySets(permitted, inheritable, effective auth.Capabili func (t *Task) DropBoundingCapability(cp linux.Capability) error { t.mu.Lock() defer t.mu.Unlock() - if !t.creds.HasCapability(linux.CAP_SETPCAP) { + creds := t.Credentials() + if !creds.HasCapability(linux.CAP_SETPCAP) { return syserror.EPERM } - t.creds = t.creds.Fork() // See doc for creds. - t.creds.BoundingCaps &^= auth.CapabilitySetOf(cp) + creds = creds.Fork() // The credentials object is immutable. See doc for creds. + creds.BoundingCaps &^= auth.CapabilitySetOf(cp) + t.creds.Store(creds) return nil } @@ -402,31 +415,33 @@ func (t *Task) SetUserNamespace(ns *auth.UserNamespace) error { t.mu.Lock() defer t.mu.Unlock() + creds := t.Credentials() // "A process reassociating itself with a user namespace must have the // CAP_SYS_ADMIN capability in the target user namespace." - setns(2) // // If t just created ns, then t.creds is guaranteed to have CAP_SYS_ADMIN // in ns (by rule 3 in auth.Credentials.HasCapability). - if !t.creds.HasCapabilityIn(linux.CAP_SYS_ADMIN, ns) { + if !creds.HasCapabilityIn(linux.CAP_SYS_ADMIN, ns) { return syserror.EPERM } - t.creds = t.creds.Fork() // See doc for creds. - t.creds.UserNamespace = ns + creds = creds.Fork() // The credentials object is immutable. See doc for creds. + creds.UserNamespace = ns // "The child process created by clone(2) with the CLONE_NEWUSER flag // starts out with a complete set of capabilities in the new user // namespace. Likewise, a process that creates a new user namespace using // unshare(2) or joins an existing user namespace using setns(2) gains a // full set of capabilities in that namespace." - t.creds.PermittedCaps = auth.AllCapabilities - t.creds.InheritableCaps = 0 - t.creds.EffectiveCaps = auth.AllCapabilities - t.creds.BoundingCaps = auth.AllCapabilities + creds.PermittedCaps = auth.AllCapabilities + creds.InheritableCaps = 0 + creds.EffectiveCaps = auth.AllCapabilities + creds.BoundingCaps = auth.AllCapabilities // "A call to clone(2), unshare(2), or setns(2) using the CLONE_NEWUSER // flag sets the "securebits" flags (see capabilities(7)) to their default // values (all flags disabled) in the child (for clone(2)) or caller (for // unshare(2), or setns(2)." - user_namespaces(7) - t.creds.KeepCaps = false + creds.KeepCaps = false + t.creds.Store(creds) return nil } @@ -435,8 +450,9 @@ func (t *Task) SetUserNamespace(ns *auth.UserNamespace) error { func (t *Task) SetKeepCaps(k bool) { t.mu.Lock() defer t.mu.Unlock() - t.creds = t.creds.Fork() // See doc for creds. - t.creds.KeepCaps = k + creds := t.Credentials().Fork() // The credentials object is immutable. See doc for creds. + creds.KeepCaps = k + t.creds.Store(creds) } // updateCredsForExec updates t.creds to reflect an execve(). @@ -512,15 +528,16 @@ func (t *Task) updateCredsForExecLocked() { // the effective user ID. var newPermitted auth.CapabilitySet // since F(inheritable) == F(permitted) == 0 fileEffective := false - root := t.creds.UserNamespace.MapToKUID(auth.RootUID) - if t.creds.EffectiveKUID == root || t.creds.RealKUID == root { - newPermitted = t.creds.InheritableCaps | t.creds.BoundingCaps - if t.creds.EffectiveKUID == root { + creds := t.Credentials() + root := creds.UserNamespace.MapToKUID(auth.RootUID) + if creds.EffectiveKUID == root || creds.RealKUID == root { + newPermitted = creds.InheritableCaps | creds.BoundingCaps + if creds.EffectiveKUID == root { fileEffective = true } } - t.creds = t.creds.Fork() // See doc for creds. + creds = creds.Fork() // The credentials object is immutable. See doc for creds. // Now we enter poorly-documented, somewhat confusing territory. (The // accompanying comment in Linux's security/commoncap.c:cap_bprm_set_creds @@ -562,27 +579,28 @@ func (t *Task) updateCredsForExecLocked() { // But since no_new_privs is always set (A3 is always true), this becomes // much simpler. If B1 and B2 are false, C2 is a no-op. If B3 is false, C1 // is a no-op. So we can just do C1 and C2 unconditionally. - if t.creds.EffectiveKUID != t.creds.RealKUID || t.creds.EffectiveKGID != t.creds.RealKGID { - t.creds.EffectiveKUID = t.creds.RealKUID - t.creds.EffectiveKGID = t.creds.RealKGID + if creds.EffectiveKUID != creds.RealKUID || creds.EffectiveKGID != creds.RealKGID { + creds.EffectiveKUID = creds.RealKUID + creds.EffectiveKGID = creds.RealKGID t.parentDeathSignal = 0 } // (Saved set-user-ID is always set to the new effective user ID, and saved // set-group-ID is always set to the new effective group ID, regardless of // the above.) - t.creds.SavedKUID = t.creds.RealKUID - t.creds.SavedKGID = t.creds.RealKGID - t.creds.PermittedCaps &= newPermitted + creds.SavedKUID = creds.RealKUID + creds.SavedKGID = creds.RealKGID + creds.PermittedCaps &= newPermitted if fileEffective { - t.creds.EffectiveCaps = t.creds.PermittedCaps + creds.EffectiveCaps = creds.PermittedCaps } else { - t.creds.EffectiveCaps = 0 + creds.EffectiveCaps = 0 } // prctl(2): The "keep capabilities" value will be reset to 0 on subsequent // calls to execve(2). - t.creds.KeepCaps = false + creds.KeepCaps = false // "The bounding set is inherited at fork(2) from the thread's parent, and // is preserved across an execve(2)". So we're done. + t.creds.Store(creds) } diff --git a/pkg/sentry/kernel/task_start.go b/pkg/sentry/kernel/task_start.go index 9458f5c2a..72caae537 100644 --- a/pkg/sentry/kernel/task_start.go +++ b/pkg/sentry/kernel/task_start.go @@ -119,7 +119,6 @@ func (ts *TaskSet) newTask(cfg *TaskConfig) (*Task, error) { ptraceTracees: make(map[*Task]struct{}), allowedCPUMask: cfg.AllowedCPUMask.Copy(), ioUsage: &usage.IO{}, - creds: cfg.Credentials, niceness: cfg.Niceness, netns: cfg.NetworkNamespaced, utsns: cfg.UTSNamespace, @@ -129,6 +128,7 @@ func (ts *TaskSet) newTask(cfg *TaskConfig) (*Task, error) { futexWaiter: futex.NewWaiter(), containerID: cfg.ContainerID, } + t.creds.Store(cfg.Credentials) t.endStopCond.L = &t.tg.signalHandlers.mu t.ptraceTracer.Store((*Task)(nil)) // We don't construct t.blockingTimer until Task.run(); see that function |