diff options
author | Rustam Kovhaev <rkovhaev@gmail.com> | 2020-10-13 16:48:17 -0700 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-10-29 09:07:16 +0100 |
commit | d2918cca649f7457018f2c94176a8302e7a9f311 (patch) | |
tree | 27c91e6194960fc439d7caef2bda88ab6b708d82 /fs | |
parent | 699cbe4895d54792114e7231e0d4195b3ec8d986 (diff) |
ntfs: add check for mft record size in superblock
[ Upstream commit 4f8c94022f0bc3babd0a124c0a7dcdd7547bd94e ]
Number of bytes allocated for mft record should be equal to the mft record
size stored in ntfs superblock as reported by syzbot, userspace might
trigger out-of-bounds read by dereferencing ctx->attr in ntfs_attr_find()
Reported-by: syzbot+aed06913f36eff9b544e@syzkaller.appspotmail.com
Signed-off-by: Rustam Kovhaev <rkovhaev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: syzbot+aed06913f36eff9b544e@syzkaller.appspotmail.com
Acked-by: Anton Altaparmakov <anton@tuxera.com>
Link: https://syzkaller.appspot.com/bug?extid=aed06913f36eff9b544e
Link: https://lkml.kernel.org/r/20200824022804.226242-1-rkovhaev@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/ntfs/inode.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/fs/ntfs/inode.c b/fs/ntfs/inode.c index 7c410f879412..2aa073b82d30 100644 --- a/fs/ntfs/inode.c +++ b/fs/ntfs/inode.c @@ -1844,6 +1844,12 @@ int ntfs_read_inode_mount(struct inode *vi) brelse(bh); } + if (le32_to_cpu(m->bytes_allocated) != vol->mft_record_size) { + ntfs_error(sb, "Incorrect mft record size %u in superblock, should be %u.", + le32_to_cpu(m->bytes_allocated), vol->mft_record_size); + goto err_out; + } + /* Apply the mst fixups. */ if (post_read_mst_fixup((NTFS_RECORD*)m, vol->mft_record_size)) { /* FIXME: Try to use the $MFTMirr now. */ |