diff options
Diffstat (limited to 'pkg/sentry/mm/procfs.go')
| -rw-r--r-- | pkg/sentry/mm/procfs.go | 92 |
1 files changed, 72 insertions, 20 deletions
diff --git a/pkg/sentry/mm/procfs.go b/pkg/sentry/mm/procfs.go index a8819aa84..8c2246bb4 100644 --- a/pkg/sentry/mm/procfs.go +++ b/pkg/sentry/mm/procfs.go @@ -58,6 +58,34 @@ func (mm *MemoryManager) NeedsUpdate(generation int64) bool { return true } +// ReadMapsDataInto is called by fsimpl/proc.mapsData.Generate to +// implement /proc/[pid]/maps. +func (mm *MemoryManager) ReadMapsDataInto(ctx context.Context, buf *bytes.Buffer) { + mm.mappingMu.RLock() + defer mm.mappingMu.RUnlock() + var start usermem.Addr + + for vseg := mm.vmas.LowerBoundSegment(start); vseg.Ok(); vseg = vseg.NextSegment() { + // FIXME(b/30793614): If we use a usermem.Addr for the handle, we get + // "panic: autosave error: type usermem.Addr is not registered". + mm.appendVMAMapsEntryLocked(ctx, vseg, buf) + } + + // We always emulate vsyscall, so advertise it here. Everything about a + // vsyscall region is static, so just hard code the maps entry since we + // don't have a real vma backing it. The vsyscall region is at the end of + // the virtual address space so nothing should be mapped after it (if + // something is really mapped in the tiny ~10 MiB segment afterwards, we'll + // get the sorting on the maps file wrong at worst; but that's not possible + // on any current platform). + // + // Artifically adjust the seqfile handle so we only output vsyscall entry once. + if start != vsyscallEnd { + // FIXME(b/30793614): Can't get a pointer to constant vsyscallEnd. + buf.WriteString(vsyscallMapsEntry) + } +} + // ReadMapsSeqFileData is called by fs/proc.mapsData.ReadSeqFileData to // implement /proc/[pid]/maps. func (mm *MemoryManager) ReadMapsSeqFileData(ctx context.Context, handle seqfile.SeqHandle) ([]seqfile.SeqData, int64) { @@ -151,6 +179,27 @@ func (mm *MemoryManager) appendVMAMapsEntryLocked(ctx context.Context, vseg vmaI b.WriteString("\n") } +// ReadSmapsDataInto is called by fsimpl/proc.smapsData.Generate to +// implement /proc/[pid]/maps. +func (mm *MemoryManager) ReadSmapsDataInto(ctx context.Context, buf *bytes.Buffer) { + mm.mappingMu.RLock() + defer mm.mappingMu.RUnlock() + var start usermem.Addr + + for vseg := mm.vmas.LowerBoundSegment(start); vseg.Ok(); vseg = vseg.NextSegment() { + // FIXME(b/30793614): If we use a usermem.Addr for the handle, we get + // "panic: autosave error: type usermem.Addr is not registered". + mm.vmaSmapsEntryIntoLocked(ctx, vseg, buf) + } + + // We always emulate vsyscall, so advertise it here. See + // ReadMapsSeqFileData for additional commentary. + if start != vsyscallEnd { + // FIXME(b/30793614): Can't get a pointer to constant vsyscallEnd. + buf.WriteString(vsyscallSmapsEntry) + } +} + // ReadSmapsSeqFileData is called by fs/proc.smapsData.ReadSeqFileData to // implement /proc/[pid]/smaps. func (mm *MemoryManager) ReadSmapsSeqFileData(ctx context.Context, handle seqfile.SeqHandle) ([]seqfile.SeqData, int64) { @@ -190,7 +239,12 @@ func (mm *MemoryManager) ReadSmapsSeqFileData(ctx context.Context, handle seqfil // Preconditions: mm.mappingMu must be locked. func (mm *MemoryManager) vmaSmapsEntryLocked(ctx context.Context, vseg vmaIterator) []byte { var b bytes.Buffer - mm.appendVMAMapsEntryLocked(ctx, vseg, &b) + mm.vmaSmapsEntryIntoLocked(ctx, vseg, &b) + return b.Bytes() +} + +func (mm *MemoryManager) vmaSmapsEntryIntoLocked(ctx context.Context, vseg vmaIterator, b *bytes.Buffer) { + mm.appendVMAMapsEntryLocked(ctx, vseg, b) vma := vseg.ValuePtr() // We take mm.activeMu here in each call to vmaSmapsEntryLocked, instead of @@ -211,40 +265,40 @@ func (mm *MemoryManager) vmaSmapsEntryLocked(ctx context.Context, vseg vmaIterat } mm.activeMu.RUnlock() - fmt.Fprintf(&b, "Size: %8d kB\n", vseg.Range().Length()/1024) - fmt.Fprintf(&b, "Rss: %8d kB\n", rss/1024) + fmt.Fprintf(b, "Size: %8d kB\n", vseg.Range().Length()/1024) + fmt.Fprintf(b, "Rss: %8d kB\n", rss/1024) // Currently we report PSS = RSS, i.e. we pretend each page mapped by a pma // is only mapped by that pma. This avoids having to query memmap.Mappables // for reference count information on each page. As a corollary, all pages // are accounted as "private" whether or not the vma is private; compare // Linux's fs/proc/task_mmu.c:smaps_account(). - fmt.Fprintf(&b, "Pss: %8d kB\n", rss/1024) - fmt.Fprintf(&b, "Shared_Clean: %8d kB\n", 0) - fmt.Fprintf(&b, "Shared_Dirty: %8d kB\n", 0) + fmt.Fprintf(b, "Pss: %8d kB\n", rss/1024) + fmt.Fprintf(b, "Shared_Clean: %8d kB\n", 0) + fmt.Fprintf(b, "Shared_Dirty: %8d kB\n", 0) // Pretend that all pages are dirty if the vma is writable, and clean otherwise. clean := rss if vma.effectivePerms.Write { clean = 0 } - fmt.Fprintf(&b, "Private_Clean: %8d kB\n", clean/1024) - fmt.Fprintf(&b, "Private_Dirty: %8d kB\n", (rss-clean)/1024) + fmt.Fprintf(b, "Private_Clean: %8d kB\n", clean/1024) + fmt.Fprintf(b, "Private_Dirty: %8d kB\n", (rss-clean)/1024) // Pretend that all pages are "referenced" (recently touched). - fmt.Fprintf(&b, "Referenced: %8d kB\n", rss/1024) - fmt.Fprintf(&b, "Anonymous: %8d kB\n", anon/1024) + fmt.Fprintf(b, "Referenced: %8d kB\n", rss/1024) + fmt.Fprintf(b, "Anonymous: %8d kB\n", anon/1024) // Hugepages (hugetlb and THP) are not implemented. - fmt.Fprintf(&b, "AnonHugePages: %8d kB\n", 0) - fmt.Fprintf(&b, "Shared_Hugetlb: %8d kB\n", 0) - fmt.Fprintf(&b, "Private_Hugetlb: %7d kB\n", 0) + fmt.Fprintf(b, "AnonHugePages: %8d kB\n", 0) + fmt.Fprintf(b, "Shared_Hugetlb: %8d kB\n", 0) + fmt.Fprintf(b, "Private_Hugetlb: %7d kB\n", 0) // Swap is not implemented. - fmt.Fprintf(&b, "Swap: %8d kB\n", 0) - fmt.Fprintf(&b, "SwapPss: %8d kB\n", 0) - fmt.Fprintf(&b, "KernelPageSize: %8d kB\n", usermem.PageSize/1024) - fmt.Fprintf(&b, "MMUPageSize: %8d kB\n", usermem.PageSize/1024) + fmt.Fprintf(b, "Swap: %8d kB\n", 0) + fmt.Fprintf(b, "SwapPss: %8d kB\n", 0) + fmt.Fprintf(b, "KernelPageSize: %8d kB\n", usermem.PageSize/1024) + fmt.Fprintf(b, "MMUPageSize: %8d kB\n", usermem.PageSize/1024) locked := rss if vma.mlockMode == memmap.MLockNone { locked = 0 } - fmt.Fprintf(&b, "Locked: %8d kB\n", locked/1024) + fmt.Fprintf(b, "Locked: %8d kB\n", locked/1024) b.WriteString("VmFlags: ") if vma.realPerms.Read { @@ -284,6 +338,4 @@ func (mm *MemoryManager) vmaSmapsEntryLocked(ctx context.Context, vseg vmaIterat b.WriteString("ac ") } b.WriteString("\n") - - return b.Bytes() } |