From 1017cf38dab7e725f08db82a065a18e961e7e6e5 Mon Sep 17 00:00:00 2001 From: Alexander Potapenko Date: Tue, 24 Jan 2023 12:32:34 +0100 Subject: [PATCH] btrfs: zlib: zero-initialize zlib workspace stable inclusion from stable-v5.10.168 commit f1fd16cd975397e8998660b4413d73280afabfe3 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I7URR4 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=f1fd16cd975397e8998660b4413d73280afabfe3 ---------------------------------------------------- commit eadd7deca0ad8a83edb2b894d8326c78e78635d6 upstream. KMSAN reports uses of uninitialized memory in zlib's longest_match() called on memory originating from zlib_alloc_workspace(). This issue is known by zlib maintainers and is claimed to be harmless, but to be on the safe side we'd better initialize the memory. Link: https://zlib.net/zlib_faq.html#faq36 Reported-by: syzbot+14d9e7602ebdf7ec0a60@syzkaller.appspotmail.com CC: stable@vger.kernel.org # 5.4+ Signed-off-by: Alexander Potapenko Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman Signed-off-by: zhaoxiaoqiang11 --- fs/btrfs/zlib.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/btrfs/zlib.c b/fs/btrfs/zlib.c index 05615a1099db..673d74d7f718 100644 --- a/fs/btrfs/zlib.c +++ b/fs/btrfs/zlib.c @@ -63,7 +63,7 @@ struct list_head *zlib_alloc_workspace(unsigned int level) workspacesize = max(zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL), zlib_inflate_workspacesize()); - workspace->strm.workspace = kvmalloc(workspacesize, GFP_KERNEL); + workspace->strm.workspace = kvzalloc(workspacesize, GFP_KERNEL); workspace->level = level; workspace->buf = NULL; /* -- GitLab