From: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
[ Upstream commit ce465bf94b70f03136171a62b607864f00093b19 ]
RHBZ: 1649907
Fix a crash that happens while attempting to mount a DFS referral from the same server on the root of a filesystem.
Signed-off-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/cifs/connect.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 0872188ce3c6..e508613f09ff 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -4459,11 +4459,13 @@ cifs_are_all_path_components_accessible(struct TCP_Server_Info *server,
unsigned int xid,
struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb,
- char *full_path)
+ char *full_path,
+ int added_treename)
{
int rc;
char *s;
char sep, tmp;
+ int skip = added_treename ? 1 : 0;
sep = CIFS_DIR_SEP(cifs_sb);
s = full_path;
@@ -4478,7 +4480,14 @@ cifs_are_all_path_components_accessible(struct TCP_Server_Info *server,
/* next separator */
while (*s && *s != sep)
s++;
-
+ /*
+ * if the treename is added, we then have to skip the first
+ * part within the separators
+ */
+ if (skip) {
+ skip = 0;
+ continue;
+ }
/*
* temporarily null-terminate the path at the end of
* the current component
@@ -4526,8 +4535,7 @@ static int is_path_remote(struct cifs_sb_info *cifs_sb, struct smb_vol *vol,
if (rc != -EREMOTE) {
rc = cifs_are_all_path_components_accessible(server, xid, tcon,
- cifs_sb,
- full_path);
+ cifs_sb, full_path, tcon->Flags & SMB_SHARE_IS_IN_DFS);
if (rc != 0) {
cifs_dbg(VFS, "cannot query dirs between root and final path, "
"enabling CIFS_MOUNT_USE_PREFIX_PATH\n");
--
2.20.1
