pve-kernel-qoup/patches/kernel/0047-kprobes-x86-Set-up-frame-pointer-in-kprobe-trampolin.patch
Fabian Grünbichler 321d628a98 add KPTI and related patches
picked from Ubuntu-4.13.0-23.26
2018-01-06 15:15:39 +01:00

87 lines
2.9 KiB
Diff

From f2c1440e8f0b728d48ee8ce295f4dfe495949e1f Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Tue, 3 Oct 2017 08:51:43 -0500
Subject: [PATCH 047/231] kprobes/x86: Set up frame pointer in kprobe
trampoline
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
CVE-2017-5754
Richard Weinberger saw an unwinder warning when running bcc's opensnoop:
WARNING: kernel stack frame pointer at ffff99ef4076bea0 in opensnoop:2008 has bad value 0000000000000008
unwind stack type:0 next_sp: (null) mask:0x2 graph_idx:0
...
ffff99ef4076be88: ffff99ef4076bea0 (0xffff99ef4076bea0)
ffff99ef4076be90: ffffffffac442721 (optimized_callback +0x81/0x90)
...
A lockdep stack trace was initiated from inside a kprobe handler, when
the unwinder noticed a bad frame pointer on the stack. The bad frame
pointer is related to the fact that the kprobe optprobe trampoline
doesn't save the frame pointer before calling into optimized_callback().
Reported-and-tested-by: Richard Weinberger <richard@sigma-star.at>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/7aef2f8ecd75c2f505ef9b80490412262cf4a44c.1507038547.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit ee213fc72fd67d0988525af501534f4cb924d1e9)
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
(cherry picked from commit 0f7d5518c91335584b16c7bed1c54c10b78ea76a)
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
---
arch/x86/kernel/kprobes/common.h | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kernel/kprobes/common.h b/arch/x86/kernel/kprobes/common.h
index db2182d63ed0..3fc0f9a794cb 100644
--- a/arch/x86/kernel/kprobes/common.h
+++ b/arch/x86/kernel/kprobes/common.h
@@ -3,6 +3,15 @@
/* Kprobes and Optprobes common header */
+#include <asm/asm.h>
+
+#ifdef CONFIG_FRAME_POINTER
+# define SAVE_RBP_STRING " push %" _ASM_BP "\n" \
+ " mov %" _ASM_SP ", %" _ASM_BP "\n"
+#else
+# define SAVE_RBP_STRING " push %" _ASM_BP "\n"
+#endif
+
#ifdef CONFIG_X86_64
#define SAVE_REGS_STRING \
/* Skip cs, ip, orig_ax. */ \
@@ -17,7 +26,7 @@
" pushq %r10\n" \
" pushq %r11\n" \
" pushq %rbx\n" \
- " pushq %rbp\n" \
+ SAVE_RBP_STRING \
" pushq %r12\n" \
" pushq %r13\n" \
" pushq %r14\n" \
@@ -48,7 +57,7 @@
" pushl %es\n" \
" pushl %ds\n" \
" pushl %eax\n" \
- " pushl %ebp\n" \
+ SAVE_RBP_STRING \
" pushl %edi\n" \
" pushl %esi\n" \
" pushl %edx\n" \
--
2.14.2