patches/kernel/0247-x86-dumpstack-Print-registers-for-first-stack-frame.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Josh Poimboeuf <jpoimboe@redhat.com>
   3 Date: Sun, 31 Dec 2017 10:18:07 -0600
   4 Subject: [PATCH] x86/dumpstack: Print registers for first stack frame
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 CVE-2017-5754
  10
  11 In the stack dump code, if the frame after the starting pt_regs is also
  12 a regs frame, the registers don't get printed.  Fix that.
  13
  14 Reported-by: Andy Lutomirski <luto@amacapital.net>
  15 Tested-by: Alexander Tsoy <alexander@tsoy.me>
  16 Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
  17 Cc: Andy Lutomirski <luto@kernel.org>
  18 Cc: Linus Torvalds <torvalds@linux-foundation.org>
  19 Cc: Peter Zijlstra <peterz@infradead.org>
  20 Cc: Thomas Gleixner <tglx@linutronix.de>
  21 Cc: Toralf Förster <toralf.foerster@gmx.de>
  22 Cc: stable@vger.kernel.org
  23 Fixes: 3b3fa11bc700 ("x86/dumpstack: Print any pt_regs found on the stack")
  24 Link: http://lkml.kernel.org/r/396f84491d2f0ef64eda4217a2165f5712f6a115.1514736742.git.jpoimboe@redhat.com
  25 Signed-off-by: Ingo Molnar <mingo@kernel.org>
  26 (cherry picked from commit 3ffdeb1a02be3086f1411a15c5b9c481fa28e21f)
  27 Signed-off-by: Andy Whitcroft <apw@canonical.com>
  28 Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
  29 (cherry picked from commit 3aef1ce621ae2eb0bd58e07cf9e66a859faa17cd)
  30 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
  31 ---
  32  arch/x86/kernel/dumpstack.c | 3 ++-
  33  1 file changed, 2 insertions(+), 1 deletion(-)
  34
  35 diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c
  36 index 8da5b487919f..042f80c50e3b 100644
  37 --- a/arch/x86/kernel/dumpstack.c
  38 +++ b/arch/x86/kernel/dumpstack.c
  39 @@ -115,6 +115,7 @@ void show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
  40
  41         unwind_start(&state, task, regs, stack);
  42         stack = stack ? : get_stack_pointer(task, regs);
  43 +       regs = unwind_get_entry_regs(&state, &partial);
  44
  45         /*
  46          * Iterate through the stacks, starting with the current stack pointer.
  47 @@ -132,7 +133,7 @@ void show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
  48          * - hardirq stack
  49          * - entry stack
  50          */
  51 -       for (regs = NULL; stack; stack = PTR_ALIGN(stack_info.next_sp, sizeof(long))) {
  52 +       for ( ; stack; stack = PTR_ALIGN(stack_info.next_sp, sizeof(long))) {
  53                 const char *stack_name;
  54
  55                 if (get_stack_info(stack, task, &stack_info, &visit_mask)) {
  56 --
  57 2.14.2
  58