diff options
author | Eric Biggers <ebiggers@google.com> | 2020-01-20 14:31:59 -0800 |
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committer | Eric Biggers <ebiggers@google.com> | 2020-01-22 14:49:56 -0800 |
commit | f0d07a98a070bb5e443df19c3aa55693cbca9341 (patch) | |
tree | 6ee18e57ea46e15f22d368ab3ed626ce23059502 /fs/ubifs/dir.c | |
parent | f592efe735a29c764e0d473307dab0f59665f02b (diff) |
ubifs: don't trigger assertion on invalid no-key filename
If userspace provides an invalid fscrypt no-key filename which encodes a
hash value with any of the UBIFS node type bits set (i.e. the high 3
bits), gracefully report ENOENT rather than triggering ubifs_assert().
Test case with kvm-xfstests shell:
. fs/ubifs/config
. ~/xfstests/common/encrypt
dev=$(__blkdev_to_ubi_volume /dev/vdc)
ubiupdatevol $dev -t
mount $dev /mnt -t ubifs
mkdir /mnt/edir
xfs_io -c set_encpolicy /mnt/edir
rm /mnt/edir/_,,,,,DAAAAAAAAAAAAAAAAAAAAAAAAAA
With the bug, the following assertion fails on the 'rm' command:
[ 19.066048] UBIFS error (ubi0:0 pid 379): ubifs_assert_failed: UBIFS assert failed: !(hash & ~UBIFS_S_KEY_HASH_MASK), in fs/ubifs/key.h:170
Fixes: f4f61d2cc6d8 ("ubifs: Implement encrypted filenames")
Cc: <stable@vger.kernel.org> # v4.10+
Link: https://lore.kernel.org/r/20200120223201.241390-5-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Diffstat (limited to 'fs/ubifs/dir.c')
-rw-r--r-- | fs/ubifs/dir.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c index 636c3222c230..5f937226976a 100644 --- a/fs/ubifs/dir.c +++ b/fs/ubifs/dir.c @@ -228,6 +228,8 @@ static struct dentry *ubifs_lookup(struct inode *dir, struct dentry *dentry, if (nm.hash) { ubifs_assert(c, fname_len(&nm) == 0); ubifs_assert(c, fname_name(&nm) == NULL); + if (nm.hash & ~UBIFS_S_KEY_HASH_MASK) + goto done; /* ENOENT */ dent_key_init_hash(c, &key, dir->i_ino, nm.hash); err = ubifs_tnc_lookup_dh(c, &key, dent, nm.minor_hash); } else { |