diff options
| -rw-r--r-- | fs/cifs/connect.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 579a628d1e65..7e5d4fda4936 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -32,6 +32,7 @@ #include <linux/kthread.h> #include <linux/pagevec.h> #include <linux/freezer.h> +#include <linux/namei.h> #include <asm/uaccess.h> #include <asm/processor.h> #include <net/ipv6.h> @@ -2278,6 +2279,7 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb, #ifdef CONFIG_CIFS_DFS_UPCALL struct dfs_info3_param *referrals = NULL; unsigned int num_referrals = 0; + int referral_walks_count = 0; try_mount_again: #endif full_path = NULL; @@ -2525,6 +2527,16 @@ remote_path_check: /* get referral if needed */ if (rc == -EREMOTE) { #ifdef CONFIG_CIFS_DFS_UPCALL + if (referral_walks_count > MAX_NESTED_LINKS) { + /* + * BB: when we implement proper loop detection, + * we will remove this check. But now we need it + * to prevent an indefinite loop if 'DFS tree' is + * misconfigured (i.e. has loops). + */ + rc = -ELOOP; + goto mount_fail_check; + } /* convert forward to back slashes in prepath here if needed */ if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) == 0) convert_delimiter(cifs_sb->prepath, @@ -2558,6 +2570,7 @@ remote_path_check: cleanup_volume_info(&volume_info); FreeXid(xid); kfree(full_path); + referral_walks_count++; goto try_mount_again; } #else /* No DFS support, return error on mount */ |