From: Shaurya Rane <ssrane_b23@ee.vjti.ac.in> stable inclusion from stable-v6.6.118 commit 7627864dc3121f39e220f5253a227edf472de59e category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/11561 CVE: CVE-2025-68219 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 7e4d9120cfa413dd34f4f434befc5dbe6c38b2e5 ] Add proper cleanup of ctx->source and fc->source to the cifs_parse_mount_err error handler. This ensures that memory allocated for the source strings is correctly freed on all error paths, matching the cleanup already performed in the success path by smb3_cleanup_fs_context_contents(). Pointers are also set to NULL after freeing to prevent potential double-free issues. This change fixes a memory leak originally detected by syzbot. The leak occurred when processing Opt_source mount options if an error happened after ctx->source and fc->source were successfully allocated but before the function completed. The specific leak sequence was: 1. ctx->source = smb3_fs_context_fullpath(ctx, '/') allocates memory 2. fc->source = kstrdup(ctx->source, GFP_KERNEL) allocates more memory 3. A subsequent error jumps to cifs_parse_mount_err 4. The old error handler freed passwords but not the source strings, causing the memory to leak. This issue was not addressed by commit e8c73eb7db0a ("cifs: client: fix memory leak in smb3_fs_context_parse_param"), which only fixed leaks from repeated fsconfig() calls but not this error path. Patch updated with minor change suggested by kernel test robot Reported-by: syzbot+87be6809ed9bf6d718e3@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=87be6809ed9bf6d718e3 Fixes: 24e0a1eff9e2 ("cifs: switch to new mount api") Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Shaurya Rane <ssrane_b23@ee.vjti.ac.in> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Wang Zhaolong <wangzhaolong@huaweicloud.com> --- fs/smb/client/fs_context.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/smb/client/fs_context.c b/fs/smb/client/fs_context.c index 137d03781d52..dcb619b64235 100644 --- a/fs/smb/client/fs_context.c +++ b/fs/smb/client/fs_context.c @@ -1722,10 +1722,14 @@ static int smb3_fs_context_parse_param(struct fs_context *fc, cifs_parse_mount_err: kfree_sensitive(ctx->password); ctx->password = NULL; kfree_sensitive(ctx->password2); ctx->password2 = NULL; + kfree(ctx->source); + ctx->source = NULL; + kfree(fc->source); + fc->source = NULL; return -EINVAL; } int smb3_init_fs_context(struct fs_context *fc) { -- 2.34.3