ext4: fix buffer_head leak in ext4_init_orphan_info

ext4_init_orphan_info() reads orphan file blocks with ext4_bread()
and stores the returned buffer_head in oi->of_binfo[i].ob_bh.

If ext4_bread() succeeds but the orphan block magic or checksum
validation fails, the function jumps to out_free. However, the old
out_free loop starts releasing buffers from i - 1, so the current
buffer_head at index i is skipped.

This leaks the buffer_head reference obtained by ext4_bread() on the
bad magic and bad checksum error paths.

Fix this by tracking the number of successfully read buffer_heads and
releasing exactly those buffer_heads on the error path.

Fixes: 02f310fcf4 ("ext4: Speedup ext4 orphan inode handling")
Signed-off-by: Guanghui Yang <3497809730@qq.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/tencent_B38798612A159E21450ECF959016371B0807@qq.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Guanghui Yang 2026-07-09 14:41:51 +00:00 • committed by Theodore Ts'o
commit 0570433580