Linux 2.6.22.7

Linux 2.6.22.7

[Chris Wright]

We (the -stable team) are announcing the release of the 2.6.22.7 kernel.
It contains a single security bugfix for the x86_64 architecture.
There is potential for local privilege escalation, so all x86_64 users
are certainly encouraged to upgrade.

CVE-2007-4573: x86_64: Zero extend all registers after ptrace in 32bit entry path.

I'll also be replying to this message with a copy of the patch between
2.6.22.6 and 2.6.22.7

The updated 2.6.22.y git tree can be found at:
        git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-2.6.22.y.git
and can be browsed at the normal kernel.org git web browser:
        http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.6.22.y.git;a=summary

thanks,
-chris

--------

 Makefile                     |    2 +-
 arch/x86_64/ia32/ia32entry.S |   18 +++++++++++++++---
 arch/x86_64/kernel/ptrace.c  |    4 ----
 3 files changed, 16 insertions(+), 8 deletions(-)

Summary of changes from v2.6.22.6 to v2.6.22.7
==============================================

Andi Kleen (1):
      x86_64: Zero extend all registers after ptrace in 32bit entry path.

Chris Wright (1):
      Linux 2.6.22.7

Re: Linux 2.6.22.7

[Chris Wright]

diff --git a/Makefile b/Makefile
index 3067f6a..12edea0 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 VERSION = 2
 PATCHLEVEL = 6
 SUBLEVEL = 22
-EXTRAVERSION = .6
+EXTRAVERSION = .7
 NAME = Holy Dancing Manatees, Batman!
 
 # *DOCUMENTATION*
diff --git a/arch/x86_64/ia32/ia32entry.S b/arch/x86_64/ia32/ia32entry.S
index 47565c3..0bc623a 100644
--- a/arch/x86_64/ia32/ia32entry.S
+++ b/arch/x86_64/ia32/ia32entry.S
@@ -38,6 +38,18 @@
 	movq	%rax,R8(%rsp)
 	.endm
 
+	.macro LOAD_ARGS32 offset
+	movl \offset(%rsp),%r11d
+	movl \offset+8(%rsp),%r10d
+	movl \offset+16(%rsp),%r9d
+	movl \offset+24(%rsp),%r8d
+	movl \offset+40(%rsp),%ecx
+	movl \offset+48(%rsp),%edx
+	movl \offset+56(%rsp),%esi
+	movl \offset+64(%rsp),%edi
+	movl \offset+72(%rsp),%eax
+	.endm
+	
 	.macro CFI_STARTPROC32 simple
 	CFI_STARTPROC	\simple
 	CFI_UNDEFINED	r8
@@ -152,7 +164,7 @@ sysenter_tracesys:
 	movq	$-ENOSYS,RAX(%rsp)	/* really needed? */
 	movq	%rsp,%rdi        /* &pt_regs -> arg1 */
 	call	syscall_trace_enter
-	LOAD_ARGS ARGOFFSET  /* reload args from stack in case ptrace changed it */
+	LOAD_ARGS32 ARGOFFSET  /* reload args from stack in case ptrace changed it */
 	RESTORE_REST
 	movl	%ebp, %ebp
 	/* no need to do an access_ok check here because rbp has been
@@ -255,7 +267,7 @@ cstar_tracesys:
 	movq $-ENOSYS,RAX(%rsp)	/* really needed? */
 	movq %rsp,%rdi        /* &pt_regs -> arg1 */
 	call syscall_trace_enter
-	LOAD_ARGS ARGOFFSET  /* reload args from stack in case ptrace changed it */
+	LOAD_ARGS32 ARGOFFSET  /* reload args from stack in case ptrace changed it */
 	RESTORE_REST
 	movl RSP-ARGOFFSET(%rsp), %r8d
 	/* no need to do an access_ok check here because r8 has been
@@ -333,7 +345,7 @@ ia32_tracesys:
 	movq $-ENOSYS,RAX(%rsp)	/* really needed? */
 	movq %rsp,%rdi        /* &pt_regs -> arg1 */
 	call syscall_trace_enter
-	LOAD_ARGS ARGOFFSET  /* reload args from stack in case ptrace changed it */
+	LOAD_ARGS32 ARGOFFSET  /* reload args from stack in case ptrace changed it */
 	RESTORE_REST
 	jmp ia32_do_syscall
 END(ia32_syscall)
diff --git a/arch/x86_64/kernel/ptrace.c b/arch/x86_64/kernel/ptrace.c
index 9409117..8d89d8c 100644
--- a/arch/x86_64/kernel/ptrace.c
+++ b/arch/x86_64/kernel/ptrace.c
@@ -223,10 +223,6 @@ static int putreg(struct task_struct *child,
 {
 	unsigned long tmp; 
 	
-	/* Some code in the 64bit emulation may not be 64bit clean.
-	   Don't take any chances. */
-	if (test_tsk_thread_flag(child, TIF_IA32))
-		value &= 0xffffffff;
 	switch (regno) {
 		case offsetof(struct user_regs_struct,fs):
 			if (value && (value & 3) != 3)