[meta-freescale] [meta-fsl-ppc][PATCH 2/5] kernel-auditsc: CVE-2014-3917

[Sona Sarmadi]

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 at enea.com>
---
 .../linux/files/auditsc-CVE-2014-3917.patch        | 91 ++++++++++++++++++++++
 recipes-kernel/linux/linux-qoriq_3.12.bb           |  1 +
 2 files changed, 92 insertions(+)
 create mode 100644 recipes-kernel/linux/files/auditsc-CVE-2014-3917.patch

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 at 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 at amacapital.net>
+Signed-off-by: Eric Paris <eparis at redhat.com>
+Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
+Signed-off-by: Jiri Slaby <jslaby at suse.cz>
+Signed-off-by: Sona Sarmadi <sona.sarmadi at 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"
 
-- 
1.9.1