From 66a3b14e118e90db80f96fcab52af4df35bc2377 Mon Sep 17 00:00:00 2001

From: Adam Jackson <ajax@redhat.com>

Date: Mon, 10 Dec 2007 11:26:57 -0500

Subject: [PATCH] Hack for proper MIT-SHM rejection for ssh-forwarded clients.

---

 Xext/shm.c |   16 ++++++++++++++++

 1 file changed, 16 insertions(+)

diff --git a/Xext/shm.c b/Xext/shm.c

index de48020..c011210 100644

--- a/Xext/shm.c

+++ b/Xext/shm.c

@@ -321,8 +321,21 @@ shm_access(ClientPtr client, SHMPERM_TYPE * perm, int readonly)

     mode_t mask;

     int uidset = 0, gidset = 0;

     LocalClientCredRec *lcc;

+    Bool is_ssh = FALSE;

     if (GetLocalClientCreds(client, &lcc) != -1) {

+#ifdef linux

+	if (lcc->fieldsSet & LCC_PID_SET) {

+	    /* ssh isn't actually a local client */

+	    char exe[64], buf[64];

+

+	    memset(buf, 0, 64);

+	    snprintf(exe, 64, "/proc/%d/exe", lcc->pid);

+	    readlink(exe, buf, 63);

+	    if (strstr(buf, "/ssh"))

+		is_ssh = TRUE;

+	}

+#endif

         if (lcc->fieldsSet & LCC_UID_SET) {

             uid = lcc->euid;

@@ -342,6 +355,9 @@ shm_access(ClientPtr client, SHMPERM_TYPE * perm, int readonly)

 #endif

         FreeLocalClientCreds(lcc);

+        if (is_ssh)

+            return -1;

+

         if (uidset) {

             /* User id 0 always gets access */

             if (uid == 0) {

-- 

1.7.10.1