cifs: Fix an error pointer dereference in cifs_mount()

Dan Carpenter · Steve French · commit 20b135e48cdd · 2020-08-06T22:06:10.000-05:00
The error handling calls kfree(full_path) so we can't let it be a NULL pointer. There used to be a NULL assignment here but we accidentally deleted it. Add it back. Fixes: 7efd081 ("cifs: document and cleanup dfs mount") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
@@ -4886,6 +4886,7 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *vol)
 		full_path = build_unc_path_to_root(vol, cifs_sb, !!count);
 		if (IS_ERR(full_path)) {
 			rc = PTR_ERR(full_path);
+			full_path = NULL;
 			break;
 		}
 		/* Chase referral */

Original file line number	Diff line number	Diff line change
`@@ -4886,6 +4886,7 @@ int cifs_mount(struct cifs_sb_info cifs_sb, struct smb_vol vol)`
`4886`	`4886`	`full_path = build_unc_path_to_root(vol, cifs_sb, !!count);`
`4887`	`4887`	`if (IS_ERR(full_path)) {`
`4888`	`4888`	`rc = PTR_ERR(full_path);`
	`4889`	`+ full_path = NULL;`
`4889`	`4890`	`break;`
`4890`	`4891`	`}`
`4891`	`4892`	`/* Chase referral */`