diff options
| author | Jamie Liu <jamieliu@google.com> | 2021-09-16 12:10:03 -0700 |
|---|---|---|
| committer | gVisor bot <gvisor-bot@google.com> | 2021-09-16 12:12:59 -0700 |
| commit | 51b96514cd9397870b39506e3693017a355319dd (patch) | |
| tree | 46f465ed03e12efdff1625886604558968d94f56 /pkg/sentry/mm | |
| parent | 282a4dd52b337dccfb578e9d32dd1005c864dd8d (diff) | |
Limit most file mmaps to the range of an int64.
In the general case, files may have offsets between MaxInt64 and MaxUint64; in
Linux pgoff is consistently represented by an unsigned long, and in gVisor the
offset types in memmap.MappableRange are uint64. However, regular file mmap is
constrained to int64 offsets (on 64-bit systems) by
mm/mmap.c:file_mmap_size_max() => MAX_LFS_FILESIZE == LLONG_MAX.
As a related fix, check for chunkStart overflow in fsutil.HostFileMapper; chunk
offsets are uint64s, but as noted above some file types may use uint64 offsets
beyond MaxInt64.
Reported-by: syzbot+71342a1585aed97ed9f7@syzkaller.appspotmail.com
PiperOrigin-RevId: 397136751
Diffstat (limited to 'pkg/sentry/mm')
| -rw-r--r-- | pkg/sentry/mm/syscalls.go | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/pkg/sentry/mm/syscalls.go b/pkg/sentry/mm/syscalls.go index 9e00c2cec..dc12ad357 100644 --- a/pkg/sentry/mm/syscalls.go +++ b/pkg/sentry/mm/syscalls.go @@ -89,7 +89,7 @@ func (mm *MemoryManager) MMap(ctx context.Context, opts memmap.MMapOpts) (hostar } // Offset + length must not overflow. if end := opts.Offset + opts.Length; end < opts.Offset { - return 0, linuxerr.ENOMEM + return 0, linuxerr.EOVERFLOW } } else { opts.Offset = 0 |