diff options
| author | Filipe Manana <fdmanana@suse.com> | 2025-04-09 16:17:16 +0100 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2025-05-15 14:30:50 +0200 |
| commit | 2187540b6f4d92b4bf7622244dc2cbfa61ff1855 (patch) | |
| tree | 39bc33a2d58d7a62f7adbc66c9ae23cff27100ab /fs/btrfs/extent-io-tree.c | |
| parent | f389e7b982a14421dc6ec935552c39ea23da2f43 (diff) | |
btrfs: exit after state split error at btrfs_clear_extent_bit_changeset()
If split_state() returned an error we call extent_io_tree_panic() which
will trigger a BUG() call. However if CONFIG_BUG is disabled, which is an
uncommon and exotic scenario, then we fallthrough and hit a use after free
when calling clear_state_bit() since the extent state record which the
local variable 'prealloc' points to was freed by split_state().
So jump to the label 'out' after calling extent_io_tree_panic() and set
the 'prealloc' pointer to NULL since split_state() has already freed it
when it hit an error.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/extent-io-tree.c')
| -rw-r--r-- | fs/btrfs/extent-io-tree.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/fs/btrfs/extent-io-tree.c b/fs/btrfs/extent-io-tree.c index 15400a0f899c..b868313e777e 100644 --- a/fs/btrfs/extent-io-tree.c +++ b/fs/btrfs/extent-io-tree.c @@ -712,8 +712,11 @@ hit_next: if (!prealloc) goto search_again; err = split_state(tree, state, prealloc, end + 1); - if (err) + if (err) { extent_io_tree_panic(tree, state, "split", err); + prealloc = NULL; + goto out; + } if (wake) wake_up(&state->wq); |