diff options
| author | Filipe Manana <fdmanana@suse.com> | 2022-02-17 13:12:08 +0100 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2022-03-14 13:13:52 +0100 |
| commit | b2d9f2dc019fb739b8c0765ddcc184c31f7ae54b (patch) | |
| tree | efd6108e74d75282bc465756bea8d501f615eeb8 | |
| parent | btrfs: fix unexpected error path when reflinking an inline extent (diff) | |
| download | linux-b2d9f2dc019fb739b8c0765ddcc184c31f7ae54b.tar.xz linux-b2d9f2dc019fb739b8c0765ddcc184c31f7ae54b.zip | |
btrfs: deal with unexpected extent type during reflinking
Smatch complains about a possible dereference of a pointer that was not
initialized:
CC [M] fs/btrfs/reflink.o
CHECK fs/btrfs/reflink.c
fs/btrfs/reflink.c:533 btrfs_clone() error: potentially dereferencing uninitialized 'trans'.
This is because we are not dealing with the case where the type of a file
extent has an unexpected value (not regular, not prealloc and not inline),
in which case the transaction handle pointer is not initialized.
Such unexpected type should be impossible, except in case of some memory
corruption caused either by bad hardware or some software bug causing
something like a buffer overrun.
So ASSERT that if the extent type is neither regular nor prealloc, then
it must be inline. Bail out with -EUCLEAN and a warning in case it is
not. This silences smatch.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
| -rw-r--r-- | fs/btrfs/reflink.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/fs/btrfs/reflink.c b/fs/btrfs/reflink.c index 07e19e069c84..03d60db0c5a3 100644 --- a/fs/btrfs/reflink.c +++ b/fs/btrfs/reflink.c @@ -494,7 +494,8 @@ process_slot: &clone_info, &trans); if (ret) goto out; - } else if (type == BTRFS_FILE_EXTENT_INLINE) { + } else { + ASSERT(type == BTRFS_FILE_EXTENT_INLINE); /* * Inline extents always have to start at file offset 0 * and can never be bigger then the sector size. We can @@ -505,7 +506,8 @@ process_slot: */ ASSERT(key.offset == 0); ASSERT(datal <= fs_info->sectorsize); - if (WARN_ON(key.offset != 0) || + if (WARN_ON(type != BTRFS_FILE_EXTENT_INLINE) || + WARN_ON(key.offset != 0) || WARN_ON(datal > fs_info->sectorsize)) { ret = -EUCLEAN; goto out; |