diff options
| author | Diogo Jahchan Koike <djahchankoike@gmail.com> | 2024-09-24 00:22:14 +0200 |
|---|---|---|
| committer | Kent Overstreet <kent.overstreet@linux.dev> | 2024-09-28 03:46:34 +0200 |
| commit | 40d40c6bea19ff1e40fb3d33b35b354a5b35025f (patch) | |
| tree | 050d4f42f67bbf5b50c3f6ea952113419958ff8b /fs | |
| parent | bcachefs: Fix srcu warning in check_topology (diff) | |
| download | linux-40d40c6bea19ff1e40fb3d33b35b354a5b35025f.tar.xz linux-40d40c6bea19ff1e40fb3d33b35b354a5b35025f.zip | |
bcachefs: assign return error when iterating through layout
syzbot reported a null ptr deref in __copy_user [0]
In __bch2_read_super, when a corrupt backup superblock matches the
default opts offset, no error is assigned to ret and the freed superblock
gets through, possibly being assigned as the best sb in bch2_fs_open and
being later dereferenced, causing a fault. Assign EINVALID to ret when
iterating through layout.
[0]: https://syzkaller.appspot.com/bug?extid=18a5c5e8a9c856944876
Reported-by: syzbot+18a5c5e8a9c856944876@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=18a5c5e8a9c856944876
Signed-off-by: Diogo Jahchan Koike <djahchankoike@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/bcachefs/super-io.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/fs/bcachefs/super-io.c b/fs/bcachefs/super-io.c index d86d5dae54c9..b2e914841b5f 100644 --- a/fs/bcachefs/super-io.c +++ b/fs/bcachefs/super-io.c @@ -799,8 +799,10 @@ retry: i < layout.sb_offset + layout.nr_superblocks; i++) { offset = le64_to_cpu(*i); - if (offset == opt_get(*opts, sb)) + if (offset == opt_get(*opts, sb)) { + ret = -BCH_ERR_invalid; continue; + } ret = read_one_super(sb, offset, &err); if (!ret) |