diff mbox

[3.8.y.z,extended,stable] Patch "microblaze: fix clone syscall" has been added to staging queue

Message ID 1376606882-23302-1-git-send-email-kamal@canonical.com
State New
Headers show

Commit Message

Kamal Mostafa Aug. 15, 2013, 10:48 p.m. UTC 
This is a note to let you know that I have just added a patch titled

    microblaze: fix clone syscall

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.7.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

From 4db3e074ae012ac65c0968fe399cf40127e43ca2 Mon Sep 17 00:00:00 2001
From: Michal Simek <michal.simek@xilinx.com>
Date: Tue, 13 Aug 2013 16:00:53 -0700
Subject: microblaze: fix clone syscall

commit dfa9771a7c4784bafd0673bc7abcee3813088b77 upstream.

Fix inadvertent breakage in the clone syscall ABI for Microblaze that
was introduced in commit f3268edbe6fe ("microblaze: switch to generic
fork/vfork/clone").

The Microblaze syscall ABI for clone takes the parent tid address in the
4th argument; the third argument slot is used for the stack size.  The
incorrectly-used CLONE_BACKWARDS type assigned parent tid to the 3rd
slot.

This commit restores the original ABI so that existing userspace libc
code will work correctly.

All kernel versions from v3.8-rc1 were affected.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
 arch/Kconfig             | 6 ++++++
 arch/microblaze/Kconfig  | 2 +-
 include/linux/syscalls.h | 5 +++++
 kernel/fork.c            | 6 ++++++
 4 files changed, 18 insertions(+), 1 deletion(-)

--
1.8.1.2
diff mbox

Patch

diff --git a/arch/Kconfig b/arch/Kconfig
index 7f8f281..acb6d03 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -373,4 +373,10 @@  config CLONE_BACKWARDS2
 	help
 	  Architecture has the first two arguments of clone(2) swapped.

+config CLONE_BACKWARDS3
+	bool
+	help
+	  Architecture has tls passed as the 3rd argument of clone(2),
+	  not the 5th one.
+
 source "kernel/gcov/Kconfig"
diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
index ba3b7c8..458991c 100644
--- a/arch/microblaze/Kconfig
+++ b/arch/microblaze/Kconfig
@@ -26,7 +26,7 @@  config MICROBLAZE
 	select GENERIC_ATOMIC64
 	select GENERIC_CLOCKEVENTS
 	select MODULES_USE_ELF_RELA
-	select CLONE_BACKWARDS
+	select CLONE_BACKWARDS3

 config SWAP
 	def_bool n
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 45e2db2..2ce3071 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -839,9 +839,14 @@  asmlinkage long sys_vfork(void);
 asmlinkage long sys_clone(unsigned long, unsigned long, int __user *, int,
 	       int __user *);
 #else
+#ifdef CONFIG_CLONE_BACKWARDS3
+asmlinkage long sys_clone(unsigned long, unsigned long, int, int __user *,
+			  int __user *, int);
+#else
 asmlinkage long sys_clone(unsigned long, unsigned long, int __user *,
 	       int __user *, int);
 #endif
+#endif

 asmlinkage long sys_execve(const char __user *filename,
 		const char __user *const __user *argv,
diff --git a/kernel/fork.c b/kernel/fork.c
index 5630e52..1c53e38 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1664,6 +1664,12 @@  SYSCALL_DEFINE5(clone, unsigned long, newsp, unsigned long, clone_flags,
 		 int __user *, parent_tidptr,
 		 int __user *, child_tidptr,
 		 int, tls_val)
+#elif defined(CONFIG_CLONE_BACKWARDS3)
+SYSCALL_DEFINE6(clone, unsigned long, clone_flags, unsigned long, newsp,
+		int, stack_size,
+		int __user *, parent_tidptr,
+		int __user *, child_tidptr,
+		int, tls_val)
 #else
 SYSCALL_DEFINE5(clone, unsigned long, clone_flags, unsigned long, newsp,
 		 int __user *, parent_tidptr,