[PATCH 5.13 256/800] smb3: fix possible access to uninitialized pointer to DACL
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-07-12 08:26:09
Also in:
lkml
Subsystem:
filesystems (vfs and infrastructure), the rest · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds
From: Steve French <redacted>
[ Upstream commit a5628263a9f8d47d9a1548fe9d5d75ba4423a735 ]
dacl_ptr can be null so we must check for it everywhere it is
used in build_sec_desc.
Addresses-Coverity: 1475598 ("Explicit null dereference")
Signed-off-by: Steve French <redacted>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/cifs/cifsacl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/cifs/cifsacl.c b/fs/cifs/cifsacl.c
index 784407f9280f..a18dee071fcd 100644
--- a/fs/cifs/cifsacl.c
+++ b/fs/cifs/cifsacl.c@@ -1308,7 +1308,7 @@ static int build_sec_desc(struct cifs_ntsd *pntsd, struct cifs_ntsd *pnntsd, ndacl_ptr = (struct cifs_acl *)((char *)pnntsd + ndacloffset); ndacl_ptr->revision = dacloffset ? dacl_ptr->revision : cpu_to_le16(ACL_REVISION); - ndacl_ptr->num_aces = dacl_ptr->num_aces; + ndacl_ptr->num_aces = dacl_ptr ? dacl_ptr->num_aces : 0; if (uid_valid(uid)) { /* chown */ uid_t id;
--
2.30.2