kernel-auditsc: CVE-2014-3917

audit_krule mask accesses need bounds checking

Reference:
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-3917

Signed-off-by: Sona Sarmadi <sona.sarmadi@enea.com>

2 files changed, 92 insertions, 0 deletions

diff --git a/recipes-kernel/linux/files/auditsc-CVE-2014-3917.patch b/recipes-kernel/linux/files/auditsc-CVE-2014-3917.patch
new file mode 100644
index 0000000..a0bdc27
--- /dev/null
+++ b/recipes-kernel/linux/files/auditsc-CVE-2014-3917.patch
@@ -0,0 +1,91 @@
+From 6004b0e5ac2e8e9e1bb0f012dc9242e03cca95df Mon Sep 17 00:00:00 2001
+From: Andy Lutomirski <luto@amacapital.net>
+Date: Wed, 28 May 2014 23:09:58 -0400
+Subject: [PATCH] auditsc: audit_krule mask accesses need bounds checking
+
+commit a3c54931199565930d6d84f4c3456f6440aefd41 upstream.
+
+Fixes an easy DoS and possible information disclosure.
+
+This does nothing about the broken state of x32 auditing.
+
+eparis: If the admin has enabled auditd and has specifically loaded
+audit rules.  This bug has been around since before git.  Wow...
+
+This fixes CVE-2014-3917
+Upstream-Status: Backport
+
+Signed-off-by: Andy Lutomirski <luto@amacapital.net>
+Signed-off-by: Eric Paris <eparis@redhat.com>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Jiri Slaby <jslaby@suse.cz>
+Signed-off-by: Sona Sarmadi <sona.sarmadi@enea.com>
+---
+ kernel/auditsc.c | 27 ++++++++++++++++++---------
+ 1 file changed, 18 insertions(+), 9 deletions(-)
+
+diff --git a/kernel/auditsc.c b/kernel/auditsc.c
+index 3b79a47..979c00b 100644
+--- a/kernel/auditsc.c
++++ b/kernel/auditsc.c
+@@ -733,6 +733,22 @@ static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
+        return AUDIT_BUILD_CONTEXT;
+ }
+ 
++static int audit_in_mask(const struct audit_krule *rule, unsigned long val)
++{
++       int word, bit;
++
++       if (val > 0xffffffff)
++               return false;
++
++       word = AUDIT_WORD(val);
++       if (word >= AUDIT_BITMASK_SIZE)
++               return false;
++
++       bit = AUDIT_BIT(val);
++
++       return rule->mask[word] & bit;
++}
++
+ /* At syscall entry and exit time, this filter is called if the
+  * audit_state is not low enough that auditing cannot take place, but is
+  * also not high enough that we already know we have to write an audit
+@@ -750,11 +766,8 @@ static enum audit_state audit_filter_syscall(struct task_struct *tsk,
+ 
+        rcu_read_lock();
+        if (!list_empty(list)) {
+-               int word = AUDIT_WORD(ctx->major);
+-               int bit  = AUDIT_BIT(ctx->major);
+-
+                list_for_each_entry_rcu(e, list, list) {
+-                       if ((e->rule.mask[word] & bit) == bit &&
++                       if (audit_in_mask(&e->rule, ctx->major) &&
+                            audit_filter_rules(tsk, &e->rule, ctx, NULL,
+                                               &state, false)) {
+                                rcu_read_unlock();
+@@ -774,20 +787,16 @@ static enum audit_state audit_filter_syscall(struct task_struct *tsk,
+ static int audit_filter_inode_name(struct task_struct *tsk,
+                                   struct audit_names *n,
+                                   struct audit_context *ctx) {
+-       int word, bit;
+        int h = audit_hash_ino((u32)n->ino);
+        struct list_head *list = &audit_inode_hash[h];
+        struct audit_entry *e;
+        enum audit_state state;
+ 
+-       word = AUDIT_WORD(ctx->major);
+-       bit  = AUDIT_BIT(ctx->major);
+-
+        if (list_empty(list))
+                return 0;
+ 
+        list_for_each_entry_rcu(e, list, list) {
+-               if ((e->rule.mask[word] & bit) == bit &&
++               if (audit_in_mask(&e->rule, ctx->major) &&
+                    audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) {
+                        ctx->current_state = state;
+                        return 1;
+-- 
+1.9.1
+
diff --git a/recipes-kernel/linux/linux-qoriq_3.12.bb b/recipes-kernel/linux/linux-qoriq_3.12.bb
index 9665632..bbbf4ba 100644
--- a/recipes-kernel/linux/linux-qoriq_3.12.bb
+++ b/recipes-kernel/linux/linux-qoriq_3.12.bb
@@ -22,6 +22,7 @@ SRC_URI = "git://git.freescale.com/ppc/sdk/linux.git;nobranch=1 \
     file://0001-net-sctp-CVE-2014-3673.patch \
     file://0002-net-sctp-CVE-2014-3687.patch \
     file://0003-net-sctp-CVE-2014-3688.patch \
+    file://auditsc-CVE-2014-3917.patch \
 "
 SRCREV = "6619b8b55796cdf0cec04b66a71288edd3057229"