git.ipfire.org Git - thirdparty/kernel/stable-queue.git/blob

   1 From ccde460b9ae5c2bd5e4742af0a7f623c2daad566 Mon Sep 17 00:00:00 2001
   2 From: He Zhe <zhe.he@windriver.com>
   3 Date: Tue, 14 Aug 2018 23:33:42 +0800
   4 Subject: x86/corruption-check: Fix panic in memory_corruption_check() when boot option without value is provided
   5
   6 From: He Zhe <zhe.he@windriver.com>
   7
   8 commit ccde460b9ae5c2bd5e4742af0a7f623c2daad566 upstream.
   9
  10 memory_corruption_check[{_period|_size}]()'s handlers do not check input
  11 argument before passing it to kstrtoul() or simple_strtoull(). The argument
  12 would be a NULL pointer if each of the kernel parameters, without its
  13 value, is set in command line and thus cause the following panic.
  14
  15 PANIC: early exception 0xe3 IP 10:ffffffff73587c22 error 0 cr2 0x0
  16 [    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.18-rc8+ #2
  17 [    0.000000] RIP: 0010:kstrtoull+0x2/0x10
  18 ...
  19 [    0.000000] Call Trace
  20 [    0.000000]  ? set_corruption_check+0x21/0x49
  21 [    0.000000]  ? do_early_param+0x4d/0x82
  22 [    0.000000]  ? parse_args+0x212/0x330
  23 [    0.000000]  ? rdinit_setup+0x26/0x26
  24 [    0.000000]  ? parse_early_options+0x20/0x23
  25 [    0.000000]  ? rdinit_setup+0x26/0x26
  26 [    0.000000]  ? parse_early_param+0x2d/0x39
  27 [    0.000000]  ? setup_arch+0x2f7/0xbf4
  28 [    0.000000]  ? start_kernel+0x5e/0x4c2
  29 [    0.000000]  ? load_ucode_bsp+0x113/0x12f
  30 [    0.000000]  ? secondary_startup_64+0xa5/0xb0
  31
  32 This patch adds checks to prevent the panic.
  33
  34 Signed-off-by: He Zhe <zhe.he@windriver.com>
  35 Cc: Linus Torvalds <torvalds@linux-foundation.org>
  36 Cc: Peter Zijlstra <peterz@infradead.org>
  37 Cc: Thomas Gleixner <tglx@linutronix.de>
  38 Cc: gregkh@linuxfoundation.org
  39 Cc: kstewart@linuxfoundation.org
  40 Cc: pombredanne@nexb.com
  41 Cc: stable@vger.kernel.org
  42 Link: http://lkml.kernel.org/r/1534260823-87917-1-git-send-email-zhe.he@windriver.com
  43 Signed-off-by: Ingo Molnar <mingo@kernel.org>
  44 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  45
  46 ---
  47  arch/x86/kernel/check.c |   15 +++++++++++++++
  48  1 file changed, 15 insertions(+)
  49
  50 --- a/arch/x86/kernel/check.c
  51 +++ b/arch/x86/kernel/check.c
  52 @@ -30,6 +30,11 @@ static __init int set_corruption_check(c
  53         ssize_t ret;
  54         unsigned long val;
  55
  56 +       if (!arg) {
  57 +               pr_err("memory_corruption_check config string not provided\n");
  58 +               return -EINVAL;
  59 +       }
  60 +
  61         ret = kstrtoul(arg, 10, &val);
  62         if (ret)
  63                 return ret;
  64 @@ -44,6 +49,11 @@ static __init int set_corruption_check_p
  65         ssize_t ret;
  66         unsigned long val;
  67
  68 +       if (!arg) {
  69 +               pr_err("memory_corruption_check_period config string not provided\n");
  70 +               return -EINVAL;
  71 +       }
  72 +
  73         ret = kstrtoul(arg, 10, &val);
  74         if (ret)
  75                 return ret;
  76 @@ -58,6 +68,11 @@ static __init int set_corruption_check_s
  77         char *end;
  78         unsigned size;
  79
  80 +       if (!arg) {
  81 +               pr_err("memory_corruption_check_size config string not provided\n");
  82 +               return -EINVAL;
  83 +       }
  84 +
  85         size = memparse(arg, &end);
  86
  87         if (*end == '\0')