[PATCH AUTOSEL 6.9 18/22] btrfs: fix uninitialized return value in the ref-verify tool

Sasha Levin
2024-07-16T14:26:38Z

From: Filipe Manana <fdmanana@suse.com>

[ Upstream commit 9da45c88e124f13a3c4d480b89b298e007fbb9e4 ]

In the ref-verify tool, when processing the inline references of an extent
item, we may end up returning with uninitialized return value, because:

1) The 'ret' variable is not initialized if there are no inline extent
references ('ptr' == 'end' before the while loop starts);

2) If we find an extent owner inline reference we don't initialize 'ret'.

So fix these cases by initializing 'ret' to 0 when declaring the variable
and set it to -EINVAL if we find an extent owner inline references and
simple quotas are not enabled (as well as print an error message).

Reported-by: Mirsad Todorovac <mtodorovac69@gmail.com>
Link: https://lore.kernel.org/linux-btrfs/59b40ebe-c824-457d-8b24-0bbca69d472b@gmail.com/
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/btrfs/ref-verify.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/ref-verify.c b/fs/btrfs/ref-verify.c
index 8c4fc98ca9ce7..aa7ddc09c55fa 100644
--- a/fs/btrfs/ref-verify.c
+++ b/fs/btrfs/ref-verify.c
@@ -441,7 +441,8 @@ static int process_extent_item(struct btrfs_fs_info *fs_info,
u32 item_size = btrfs_item_size(leaf, slot);
unsigned long end, ptr;
u64 offset, flags, count;
- int type, ret;
+ int type;
+ int ret = 0;

ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
flags = btrfs_extent_flags(leaf, ei);
@@ -486,7 +487,11 @@ static int process_extent_item(struct btrfs_fs_info *fs_info,
key->objectid, key->offset);
break;
case BTRFS_EXTENT_OWNER_REF_KEY:
- WARN_ON(!btrfs_fs_incompat(fs_info, SIMPLE_QUOTA));
+ if (!btrfs_fs_incompat(fs_info, SIMPLE_QUOTA)) {
+ btrfs_err(fs_info,
+ "found extent owner ref without simple quotas enabled");
+ ret = -EINVAL;
+ }
break;
default:
btrfs_err(fs_info, "invalid key type in iref");
--
2.43.0