From: Jeremy Allison <jra@samba.org>
Date: Tue, 31 Mar 2015 21:40:23 +0000 (-0700)
Subject: s3: libsmbclient: After getting attribute server, ensure main srv pointer is still... 
X-Git-Tag: samba-4.1.18~12
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1cd5d85cad2f2f29a5f9d2b4decd538db4e0e1d6;p=thirdparty%2Fsamba.git

s3: libsmbclient: After getting attribute server, ensure main srv pointer is still valid.

Bug #11186: Crash seen in libsmbclient due to free of server structure during SMBC_getxattr() call

Bug: https://bugzilla.samba.org/show_bug.cgi?id=11186

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: David Disseldorp <ddiss@samba.org>

Autobuild-User(master): David Disseldorp <ddiss@samba.org>
Autobuild-Date(master): Tue Apr 14 02:58:43 CEST 2015 on sn-devel-104

(cherry picked from commit 2d4db4a65e1e8924470741378fe249f22196eceb)
---

diff --git a/source3/libsmb/libsmb_xattr.c b/source3/libsmb/libsmb_xattr.c
index 8e6590a5367..edc62f3bf3e 100644
--- a/source3/libsmb/libsmb_xattr.c
+++ b/source3/libsmb/libsmb_xattr.c
@@ -2072,6 +2072,25 @@ SMBC_getxattr_ctx(SMBCCTX *context,
         if (! srv->no_nt_session) {
                 ipc_srv = SMBC_attr_server(frame, context, server, port, share,
                                            &workgroup, &user, &password);
+		/*
+		 * SMBC_attr_server() can cause the original
+		 * server to be removed from the cache.
+		 * If so we must error out here as the srv
+		 * pointer has been freed.
+		 */
+		if (smbc_getFunctionGetCachedServer(context)(context,
+				server,
+				share,
+				workgroup,
+				user) != srv) {
+#if defined(ECONNRESET)
+			errno = ECONNRESET;
+#else
+			errno = ETIMEDOUT;
+#endif
+			TALLOC_FREE(frame);
+			return -1;
+		}
                 if (! ipc_srv) {
                         srv->no_nt_session = True;
                 }
@@ -2207,9 +2226,31 @@ SMBC_removexattr_ctx(SMBCCTX *context,
         }
 
         if (! srv->no_nt_session) {
+		int saved_errno;
                 ipc_srv = SMBC_attr_server(frame, context, server, port, share,
                                            &workgroup, &user, &password);
+		saved_errno = errno;
+		/*
+		 * SMBC_attr_server() can cause the original
+		 * server to be removed from the cache.
+		 * If so we must error out here as the srv
+		 * pointer has been freed.
+		 */
+		if (smbc_getFunctionGetCachedServer(context)(context,
+				server,
+				share,
+				workgroup,
+				user) != srv) {
+#if defined(ECONNRESET)
+			errno = ECONNRESET;
+#else
+			errno = ETIMEDOUT;
+#endif
+			TALLOC_FREE(frame);
+			return -1;
+		}
                 if (! ipc_srv) {
+			errno = saved_errno;
                         srv->no_nt_session = True;
                 }
         } else {