cifs: fix potential use-after-free bugs in TCP_Server_Info::hostname

[sfrench/cifs-2.6.git] / fs / cifs / cifs_debug.h

diff --git a/fs/cifs/cifs_debug.h b/fs/cifs/cifs_debug.h
index d44808263cfba74fb8aa299f9682e902e19c6191..ce5cfd236fdb8add8b1f13c19181781e2069d173 100644 (file)
--- a/fs/cifs/cifs_debug.h
+++ b/fs/cifs/cifs_debug.h
@@ -81,19 +81,19 @@ do {                                                                        \
 
 #define cifs_server_dbg_func(ratefunc, type, fmt, ...)                 \
 do {                                                                   \
-       const char *sn = "";                                            \
-       if (server && server->hostname)                                 \
-               sn = server->hostname;                                  \
+       spin_lock(&server->srv_lock);                                   \
        if ((type) & FYI && cifsFYI & CIFS_INFO) {                      \
                pr_debug_ ## ratefunc("%s: \\\\%s " fmt,                \
-                                     __FILE__, sn, ##__VA_ARGS__);     \
+                                     __FILE__, server->hostname,       \
+                                     ##__VA_ARGS__);                   \
        } else if ((type) & VFS) {                                      \
                pr_err_ ## ratefunc("VFS: \\\\%s " fmt,                 \
-                                   sn, ##__VA_ARGS__);                 \
+                                   server->hostname, ##__VA_ARGS__);   \
        } else if ((type) & NOISY && (NOISY != 0)) {                    \
                pr_debug_ ## ratefunc("\\\\%s " fmt,                    \
-                                     sn, ##__VA_ARGS__);               \
+                                     server->hostname, ##__VA_ARGS__); \
        }                                                               \
+       spin_unlock(&server->srv_lock);                                 \
 } while (0)
 
 #define cifs_server_dbg(type, fmt, ...)                                        \