From: Dan Rosenberg <drosenberg@vsecurity.com>

Date: Wed, 27 Oct 2010 22:34:17 +0000 (-0700)

Subject: ipc: initialize structure memory to zero for compat functions

X-Git-Tag: v2.6.37-rc1~85^2~50

X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Ftorvalds%2Flinux-2.6.git;a=commitdiff_plain;h=03145beb455cf5c20a761e8451e30b8a74ba58d9

ipc: initialize structure memory to zero for compat functions

This takes care of leaking uninitialized kernel stack memory to

userspace from non-zeroed fields in structs in compat ipc functions.

Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>

Cc: Manfred Spraul <manfred@colorfullife.com>

Cc: Arnd Bergmann <arnd@arndb.de>

Cc: <stable@kernel.org>

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

---

diff --git a/ipc/compat.c b/ipc/compat.c

index 9dc2c7d..845a287 100644

--- a/ipc/compat.c

+++ b/ipc/compat.c

@@ -241,6 +241,8 @@ long compat_sys_semctl(int first, int second, int third, void __user *uptr)

 	struct semid64_ds __user *up64;

 	int version = compat_ipc_parse_version(&third);

+	memset(&s64, 0, sizeof(s64));

+

 	if (!uptr)

 		return -EINVAL;

 	if (get_user(pad, (u32 __user *) uptr))

@@ -421,6 +423,8 @@ long compat_sys_msgctl(int first, int second, void __user *uptr)

 	int version = compat_ipc_parse_version(&second);

 	void __user *p;

+	memset(&m64, 0, sizeof(m64));

+

 	switch (second & (~IPC_64)) {

 	case IPC_INFO:

 	case IPC_RMID:

@@ -594,6 +598,8 @@ long compat_sys_shmctl(int first, int second, void __user *uptr)

 	int err, err2;

 	int version = compat_ipc_parse_version(&second);

+	memset(&s64, 0, sizeof(s64));

+

 	switch (second & (~IPC_64)) {

 	case IPC_RMID:

 	case SHM_LOCK:

diff --git a/ipc/compat_mq.c b/ipc/compat_mq.c

index d8d1e9f..380ea4f 100644

--- a/ipc/compat_mq.c

+++ b/ipc/compat_mq.c

@@ -53,6 +53,9 @@ asmlinkage long compat_sys_mq_open(const char __user *u_name,

 	void __user *p = NULL;

 	if (u_attr && oflag & O_CREAT) {

 		struct mq_attr attr;

+

+		memset(&attr, 0, sizeof(attr));

+

 		p = compat_alloc_user_space(sizeof(attr));

 		if (get_compat_mq_attr(&attr, u_attr) ||

 		    copy_to_user(p, &attr, sizeof(attr)))

@@ -127,6 +130,8 @@ asmlinkage long compat_sys_mq_getsetattr(mqd_t mqdes,

 	struct mq_attr __user *p = compat_alloc_user_space(2 * sizeof(*p));

 	long ret;

+	memset(&mqstat, 0, sizeof(mqstat));

+

 	if (u_mqstat) {

 		if (get_compat_mq_attr(&mqstat, u_mqstat) ||

 		    copy_to_user(p, &mqstat, sizeof(mqstat)))