From deb6e182b5efa9e7e5b8d0c9f5e264f3c661f1eb Mon Sep 17 00:00:00 2001 From: Lizhi Xu Date: Sat, 2 Nov 2024 17:52:26 +0800 Subject: [PATCH] ocfs2: fix possible null-ptr-deref in ocfs2_set_buffer_uptodate stable inclusion from stable-v6.6.55 commit d52c5652e7dcb7a0648bbb8642cc3e617070ab49 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAYRA8 CVE: CVE-2024-49877 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d52c5652e7dcb7a0648bbb8642cc3e617070ab49 -------------------------------- commit 33b525cef4cff49e216e4133cc48452e11c0391e upstream. When doing cleanup, if flags without OCFS2_BH_READAHEAD, it may trigger NULL pointer dereference in the following ocfs2_set_buffer_uptodate() if bh is NULL. Link: https://lkml.kernel.org/r/20240902023636.1843422-3-joseph.qi@linux.alibaba.com Fixes: cf76c78595ca ("ocfs2: don't put and assigning null to bh allocated outside") Signed-off-by: Lizhi Xu Signed-off-by: Joseph Qi Reviewed-by: Joseph Qi Reported-by: Heming Zhao Suggested-by: Heming Zhao Cc: [4.20+] Cc: Changwei Ge Cc: Gang He Cc: Joel Becker Cc: Jun Piao Cc: Junxiao Bi Cc: Mark Fasheh Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman Signed-off-by: Zeng Heng --- fs/ocfs2/buffer_head_io.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/ocfs2/buffer_head_io.c b/fs/ocfs2/buffer_head_io.c index a71b40065e8b..45ca3cb7c097 100644 --- a/fs/ocfs2/buffer_head_io.c +++ b/fs/ocfs2/buffer_head_io.c @@ -388,7 +388,8 @@ int ocfs2_read_blocks(struct ocfs2_caching_info *ci, u64 block, int nr, /* Always set the buffer in the cache, even if it was * a forced read, or read-ahead which hasn't yet * completed. */ - ocfs2_set_buffer_uptodate(ci, bh); + if (bh) + ocfs2_set_buffer_uptodate(ci, bh); } ocfs2_metadata_cache_io_unlock(ci); -- Gitee