diff options
Diffstat (limited to 'trunk/2.6.18/30035_amd64-zero-extend-32bit-ptrace.patch')
-rw-r--r-- | trunk/2.6.18/30035_amd64-zero-extend-32bit-ptrace.patch | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/trunk/2.6.18/30035_amd64-zero-extend-32bit-ptrace.patch b/trunk/2.6.18/30035_amd64-zero-extend-32bit-ptrace.patch new file mode 100644 index 0000000..0f2637a --- /dev/null +++ b/trunk/2.6.18/30035_amd64-zero-extend-32bit-ptrace.patch @@ -0,0 +1,88 @@ +From: Andi Kleen <ak@suse.de> +Date: Fri, 21 Sep 2007 14:16:18 +0000 (+0200) +Subject: x86_64: Zero extend all registers after ptrace in 32bit entry path. +X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Ftorvalds%2Flinux-2.6.git;a=commitdiff_plain;h=176df2457ef6207156ca1a40991c54ca01fef567 + +x86_64: Zero extend all registers after ptrace in 32bit entry path. + +Strictly it's only needed for eax. + +It actually does a little more than strictly needed -- the other registers +are already zero extended. + +Also remove the now unnecessary and non functional compat task check +in ptrace. + +This is CVE-2007-4573 + +Found by Wojciech Purczynski + +Signed-off-by: Andi Kleen <ak@suse.de> +Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> +--- + +Adjusted to apply to Debian's 2.6.18 by dann frazier <dannf@debian.org> + +diff -urpN linux-source-2.6.18.orig/arch/x86_64/ia32/ia32entry.S linux-source-2.6.18/arch/x86_64/ia32/ia32entry.S +--- linux-source-2.6.18.orig/arch/x86_64/ia32/ia32entry.S 2006-09-19 21:42:06.000000000 -0600 ++++ linux-source-2.6.18/arch/x86_64/ia32/ia32entry.S 2007-09-25 00:10:16.089100799 -0600 +@@ -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 +@@ -151,7 +163,7 @@ 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 +@@ -253,7 +265,7 @@ 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 +@@ -330,7 +342,7 @@ 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 -urpN linux-source-2.6.18.orig/arch/x86_64/kernel/ptrace.c linux-source-2.6.18/arch/x86_64/kernel/ptrace.c +--- linux-source-2.6.18.orig/arch/x86_64/kernel/ptrace.c 2006-09-19 21:42:06.000000000 -0600 ++++ linux-source-2.6.18/arch/x86_64/kernel/ptrace.c 2007-09-25 00:10:16.089100799 -0600 +@@ -223,10 +223,6 @@ static int putreg(struct task_struct *ch + { + 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) |