This is a note to let you know that I've just added the patch titled

    arm64: check for number of arguments in syscall_get/set_arguments()

to the 3.10-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     arm64-check-for-number-of-arguments-in-syscall_get-set_arguments.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 7b22c03536a539142f931815528d55df455ffe2d Mon Sep 17 00:00:00 2001
From: AKASHI Takahiro <[email protected]>
Date: Thu, 3 Oct 2013 06:47:44 +0100
Subject: arm64: check for number of arguments in syscall_get/set_arguments()

From: AKASHI Takahiro <[email protected]>

commit 7b22c03536a539142f931815528d55df455ffe2d upstream.

In ftrace_syscall_enter(),
    syscall_get_arguments(..., 0, n, ...)
        if (i == 0) { <handle orig_x0> ...; n--;}
        memcpy(..., n * sizeof(args[0]));
If 'number of arguments(n)' is zero and 'argument index(i)' is also zero in
syscall_get_arguments(), none of arguments should be copied by memcpy().
Otherwise 'n--' can be a big positive number and unexpected amount of data
will be copied. Tracing system calls which take no argument, say sync(void),
may hit this case and eventually make the system corrupted.
This patch fixes the issue both in syscall_get_arguments() and
syscall_set_arguments().

Signed-off-by: AKASHI Takahiro <[email protected]>
Acked-by: Will Deacon <[email protected]>
Signed-off-by: Catalin Marinas <[email protected]>
Cc: Mark Brown <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 arch/arm64/include/asm/syscall.h |    6 ++++++
 1 file changed, 6 insertions(+)

--- a/arch/arm64/include/asm/syscall.h
+++ b/arch/arm64/include/asm/syscall.h
@@ -59,6 +59,9 @@ static inline void syscall_get_arguments
                                         unsigned int i, unsigned int n,
                                         unsigned long *args)
 {
+       if (n == 0)
+               return;
+
        if (i + n > SYSCALL_MAX_ARGS) {
                unsigned long *args_bad = args + SYSCALL_MAX_ARGS - i;
                unsigned int n_bad = n + i - SYSCALL_MAX_ARGS;
@@ -82,6 +85,9 @@ static inline void syscall_set_arguments
                                         unsigned int i, unsigned int n,
                                         const unsigned long *args)
 {
+       if (n == 0)
+               return;
+
        if (i + n > SYSCALL_MAX_ARGS) {
                pr_warning("%s called with max args %d, handling only %d\n",
                           __func__, i + n, SYSCALL_MAX_ARGS);


Patches currently in stable-queue which might be from 
[email protected] are

queue-3.10/arm64-check-for-number-of-arguments-in-syscall_get-set_arguments.patch
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