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* rcu: Kernel stack is corrupted in: perf_trace_rcu_dyntick
@ 2018-09-29  9:22 王晓东
  2018-10-03  2:45 ` Steven Rostedt
  2018-10-18  2:13 ` Steven Rostedt
  0 siblings, 2 replies; 6+ messages in thread
From: 王晓东 @ 2018-09-29  9:22 UTC (permalink / raw)
  To: rostedt, mingo, linux-kernel

Hi there,

We would like to report a kernel stack corrupted problem we identified
in the perf_trace_rcu_dyntick function of tracing events subsystem.
And the problem was founded by syzkaller.  We has tested the PoC on
the lasted master branch of kernel(4.19.0-rc5+).

The crash log generated with KASAN enabled:

root@pc:~# ./perf_trace_rcu_dyntick
[  582.069938] Kernel panic - not syncing: stack-protector: Kernel
stack is corrupted in: perf_trace_rcu_dyntick+0x355/0x4f0
[  582.069938]
[  582.071341] CPU: 6 PID: 3417 Comm: perf_trace_rcu_ Not tainted 4.19.0-rc5+ #1
[  582.072134] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
[  582.073103] Call Trace:
[  582.073364]  <IRQ>
[  582.073614]  dump_stack+0x8c/0xce
[  582.074039]  panic+0x1cb/0x3aa
[  582.074427]  ? refcount_error_report+0x296/0x296
[  582.075003]  ? timerqueue_del+0x71/0x130
[  582.075553]  ? perf_trace_rcu_dyntick+0x355/0x4f0
[  582.076063]  ? __stack_chk_fail+0x6/0x20
[  582.076763]  ? perf_trace_rcu_dyntick+0x355/0x4f0
[  582.077369]  __stack_chk_fail+0x1f/0x20
[  582.077877]  perf_trace_rcu_dyntick+0x355/0x4f0
[  582.078442]  ? rcu_gp_is_expedited+0xa0/0xa0
[  582.078993]  ? rcu_gp_is_expedited+0xa0/0xa0
[  582.079525]  ? check_preempt_curr+0x1c2/0x2a0
[  582.080059]  ? sched_clock_cpu+0x18/0x160
[  582.080551]  rcu_nmi_enter+0x1f0/0x2f0
[  582.081036]  ? rcu_gp_is_expedited+0xa0/0xa0
[  582.081507]  irq_enter+0xf/0x80
[  582.081914]  smp_apic_timer_interrupt+0x1b/0x2d0
[  582.082480]  apic_timer_interrupt+0xf/0x20
[  582.082984]  </IRQ>
[  582.083219] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50
[  582.087816] Code: e8 35 0b 20 00 48 8b 14 24 e9 fe fe ff ff 48 89
df e8 24 0b 20 00 e9 d9 fe ff ff 4c 89 e7 e8 17 0b 20 00 e9 ab fe ff
ff 90 90 <65> 48 8b 04 25 40 dd 01 00 65 8b 15 70 03 8f 63 81 e2 00 01
1f 00
[  582.090289] RSP: 0018:ffff8800651bf9e0 EFLAGS: 00000206 ORIG_RAX:
ffffffffffffff13
[  582.091238] RAX: 0000000000000000 RBX: ffffffff9eed12a5 RCX: ffffffff9c6ca1b6
[  582.092873] RDX: 0000000000000005 RSI: ffffffff9ee31d71 RDI: ffffffff9eed12a4
[  582.093934] RBP: 0000000000000078 R08: ffffed000d38dfb2 R09: ffffed000d38dfb1
[  582.095102] R10: 000000007350a3ba R11: ffff880069c6fd8f R12: ffff8800651bfa6e
[  582.096444] R13: 0000000000000001 R14: dffffc0000000000 R15: 000000000000006a
[  582.097414]  ? kallsyms_expand_symbol.constprop.11+0x176/0x250
[  582.098518]  kallsyms_expand_symbol.constprop.11+0x12e/0x250
[  582.099707]  kallsyms_lookup_name+0xbe/0x1d0
[  582.100369]  ? kallsyms_on_each_symbol+0x210/0x210
[  582.101436]  ? snprintf+0xbd/0xf0
[  582.102029]  ? vsprintf+0x30/0x30
[  582.102805]  ? kasan_kmalloc+0xa9/0xd0
[  582.103489]  ? alloc_trace_kprobe+0x6c0/0x930
[  582.104073]  kprobe_on_func_entry+0x57/0xb0
[  582.105421]  register_kretprobe+0x89/0xc10
[  582.105930]  ? set_print_fmt+0x32/0xa0
[  582.106376]  __register_trace_kprobe.part.10+0x14e/0x2e0
[  582.106980]  create_local_trace_kprobe+0x29c/0x3f0
[  582.107487]  perf_kprobe_init+0x15f/0x210
[  582.107912]  perf_kprobe_event_init+0xc4/0x140
[  582.108377]  perf_try_init_event+0xcb/0x290
[  582.108817]  perf_event_alloc+0x1476/0x2020
[  582.109264]  ? find_get_context.isra.106+0x690/0x690
[  582.109922]  ? __alloc_fd+0x1a3/0x4e0
[  582.120002]  __do_sys_perf_event_open+0x222/0x1f40
[  582.123049]  ? avc_has_perm_noaudit+0x340/0x340
[  582.131226]  ? perf_event_set_output+0x5f0/0x5f0
[  582.134395]  ? handle_mm_fault+0x103/0x350
[  582.138102]  ? ksys_ioctl+0x61/0x90
[  582.140234]  do_syscall_64+0x9a/0x2c0
[  582.142674]  ? prepare_exit_to_usermode+0xbc/0x150
[  582.146856]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  582.151127] RIP: 0033:0x446159
[  582.152816] Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00
00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24
08 0f 05 <48> 3d 01 f0 ff ff 0f 83 5b 08 fc ff c3 66 2e 0f 1f 84 00 00
00 00
[  582.167257] RSP: 002b:00007fffc2b023d8 EFLAGS: 00000246 ORIG_RAX:
000000000000012a
[  582.171375] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000446159
[  582.175760] RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000020000180
[  582.176487] RBP: 00007fffc2b025b0 R08: 0000000000000000 R09: 0000000000000000
[  582.177189] R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000406e40
[  582.177898] R13: 0000000000406ed0 R14: 0000000000000000 R15: 0000000000000000
[  583.353322] Shutting down cpus with NMI
[  583.354285] Kernel Offset: 0x1b400000 from 0xffffffff81000000
(relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[  583.356743] Rebooting in 86400 seconds..


This bug could be easily reproduced by running the PoC(generated by
syzkaller, and transformed to C Source code).

For any further information, please feel free to contact us at
wisedd@gmail.com. We would be more than happy to provide other
information of this problem.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: rcu: Kernel stack is corrupted in: perf_trace_rcu_dyntick
  2018-09-29  9:22 rcu: Kernel stack is corrupted in: perf_trace_rcu_dyntick 王晓东
@ 2018-10-03  2:45 ` Steven Rostedt
  2018-10-17  8:45   ` Phy Bio
  2018-10-18  2:13 ` Steven Rostedt
  1 sibling, 1 reply; 6+ messages in thread
From: Steven Rostedt @ 2018-10-03  2:45 UTC (permalink / raw)
  To: 王晓东
  Cc: mingo, linux-kernel, Masami Hiramatsu, Peter Zijlstra, Paul E. McKenney

On Sat, 29 Sep 2018 17:22:13 +0800
王晓东 <wisedd@gmail.com> wrote:

> Hi there,
> 
> We would like to report a kernel stack corrupted problem we identified
> in the perf_trace_rcu_dyntick function of tracing events subsystem.
> And the problem was founded by syzkaller.  We has tested the PoC on
> the lasted master branch of kernel(4.19.0-rc5+).
> 
> The crash log generated with KASAN enabled:
> 
> root@pc:~# ./perf_trace_rcu_dyntick
> [  582.069938] Kernel panic - not syncing: stack-protector: Kernel
> stack is corrupted in: perf_trace_rcu_dyntick+0x355/0x4f0
> [  582.069938]
> [  582.071341] CPU: 6 PID: 3417 Comm: perf_trace_rcu_ Not tainted 4.19.0-rc5+ #1
> [  582.072134] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
> BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
> [  582.073103] Call Trace:
> [  582.073364]  <IRQ>
> [  582.073614]  dump_stack+0x8c/0xce
> [  582.074039]  panic+0x1cb/0x3aa
> [  582.074427]  ? refcount_error_report+0x296/0x296
> [  582.075003]  ? timerqueue_del+0x71/0x130
> [  582.075553]  ? perf_trace_rcu_dyntick+0x355/0x4f0
> [  582.076063]  ? __stack_chk_fail+0x6/0x20
> [  582.076763]  ? perf_trace_rcu_dyntick+0x355/0x4f0
> [  582.077369]  __stack_chk_fail+0x1f/0x20
> [  582.077877]  perf_trace_rcu_dyntick+0x355/0x4f0
> [  582.078442]  ? rcu_gp_is_expedited+0xa0/0xa0
> [  582.078993]  ? rcu_gp_is_expedited+0xa0/0xa0
> [  582.079525]  ? check_preempt_curr+0x1c2/0x2a0
> [  582.080059]  ? sched_clock_cpu+0x18/0x160
> [  582.080551]  rcu_nmi_enter+0x1f0/0x2f0
> [  582.081036]  ? rcu_gp_is_expedited+0xa0/0xa0
> [  582.081507]  irq_enter+0xf/0x80
> [  582.081914]  smp_apic_timer_interrupt+0x1b/0x2d0
> [  582.082480]  apic_timer_interrupt+0xf/0x20
> [  582.082984]  </IRQ>
> [  582.083219] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50
> [  582.087816] Code: e8 35 0b 20 00 48 8b 14 24 e9 fe fe ff ff 48 89
> df e8 24 0b 20 00 e9 d9 fe ff ff 4c 89 e7 e8 17 0b 20 00 e9 ab fe ff
> ff 90 90 <65> 48 8b 04 25 40 dd 01 00 65 8b 15 70 03 8f 63 81 e2 00 01
> 1f 00
> [  582.090289] RSP: 0018:ffff8800651bf9e0 EFLAGS: 00000206 ORIG_RAX:
> ffffffffffffff13
> [  582.091238] RAX: 0000000000000000 RBX: ffffffff9eed12a5 RCX: ffffffff9c6ca1b6
> [  582.092873] RDX: 0000000000000005 RSI: ffffffff9ee31d71 RDI: ffffffff9eed12a4
> [  582.093934] RBP: 0000000000000078 R08: ffffed000d38dfb2 R09: ffffed000d38dfb1
> [  582.095102] R10: 000000007350a3ba R11: ffff880069c6fd8f R12: ffff8800651bfa6e
> [  582.096444] R13: 0000000000000001 R14: dffffc0000000000 R15: 000000000000006a
> [  582.097414]  ? kallsyms_expand_symbol.constprop.11+0x176/0x250
> [  582.098518]  kallsyms_expand_symbol.constprop.11+0x12e/0x250
> [  582.099707]  kallsyms_lookup_name+0xbe/0x1d0
> [  582.100369]  ? kallsyms_on_each_symbol+0x210/0x210
> [  582.101436]  ? snprintf+0xbd/0xf0
> [  582.102029]  ? vsprintf+0x30/0x30
> [  582.102805]  ? kasan_kmalloc+0xa9/0xd0
> [  582.103489]  ? alloc_trace_kprobe+0x6c0/0x930
> [  582.104073]  kprobe_on_func_entry+0x57/0xb0

I'm curious to what kretprobe was used.

-- Steve

> [  582.105421]  register_kretprobe+0x89/0xc10
> [  582.105930]  ? set_print_fmt+0x32/0xa0
> [  582.106376]  __register_trace_kprobe.part.10+0x14e/0x2e0
> [  582.106980]  create_local_trace_kprobe+0x29c/0x3f0
> [  582.107487]  perf_kprobe_init+0x15f/0x210
> [  582.107912]  perf_kprobe_event_init+0xc4/0x140
> [  582.108377]  perf_try_init_event+0xcb/0x290
> [  582.108817]  perf_event_alloc+0x1476/0x2020
> [  582.109264]  ? find_get_context.isra.106+0x690/0x690
> [  582.109922]  ? __alloc_fd+0x1a3/0x4e0
> [  582.120002]  __do_sys_perf_event_open+0x222/0x1f40
> [  582.123049]  ? avc_has_perm_noaudit+0x340/0x340
> [  582.131226]  ? perf_event_set_output+0x5f0/0x5f0
> [  582.134395]  ? handle_mm_fault+0x103/0x350
> [  582.138102]  ? ksys_ioctl+0x61/0x90
> [  582.140234]  do_syscall_64+0x9a/0x2c0
> [  582.142674]  ? prepare_exit_to_usermode+0xbc/0x150
> [  582.146856]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
> [  582.151127] RIP: 0033:0x446159
> [  582.152816] Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00
> 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24
> 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 5b 08 fc ff c3 66 2e 0f 1f 84 00 00
> 00 00
> [  582.167257] RSP: 002b:00007fffc2b023d8 EFLAGS: 00000246 ORIG_RAX:
> 000000000000012a
> [  582.171375] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000446159
> [  582.175760] RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000020000180
> [  582.176487] RBP: 00007fffc2b025b0 R08: 0000000000000000 R09: 0000000000000000
> [  582.177189] R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000406e40
> [  582.177898] R13: 0000000000406ed0 R14: 0000000000000000 R15: 0000000000000000
> [  583.353322] Shutting down cpus with NMI
> [  583.354285] Kernel Offset: 0x1b400000 from 0xffffffff81000000
> (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
> [  583.356743] Rebooting in 86400 seconds..
> 
> 
> This bug could be easily reproduced by running the PoC(generated by
> syzkaller, and transformed to C Source code).
> 
> For any further information, please feel free to contact us at
> wisedd@gmail.com. We would be more than happy to provide other
> information of this problem.


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: rcu: Kernel stack is corrupted in: perf_trace_rcu_dyntick
  2018-10-03  2:45 ` Steven Rostedt
@ 2018-10-17  8:45   ` Phy Bio
  2018-10-17 10:43     ` Paul E. McKenney
  0 siblings, 1 reply; 6+ messages in thread
From: Phy Bio @ 2018-10-17  8:45 UTC (permalink / raw)
  To: rostedt; +Cc: mingo, linux-kernel, mhiramat, peterz, paulmck

I will be very happy, if the source code can help you analyze this problem.

The source code is in the following:

#define _GNU_SOURCE

#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/prctl.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>

unsigned long long procid;

static void sleep_ms(uint64_t ms)
{
  usleep(ms * 1000);
}

static uint64_t current_time_ms(void)
{
  struct timespec ts;
  if (clock_gettime(CLOCK_MONOTONIC, &ts))
    exit(1);
  return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000;
}

#define BITMASK_LEN(type, bf_len) (type)((1ull << (bf_len)) - 1)

#define BITMASK_LEN_OFF(type, bf_off, bf_len)                                  \
  (type)(BITMASK_LEN(type, (bf_len)) << (bf_off))

#define STORE_BY_BITMASK(type, addr, val, bf_off, bf_len)                      \
  if ((bf_off) == 0 && (bf_len) == 0) {                                        \
    *(type*)(addr) = (type)(val);                                              \
  } else {                                                                     \
    type new_val = *(type*)(addr);                                             \
    new_val &= ~BITMASK_LEN_OFF(type, (bf_off), (bf_len));                     \
    new_val |= ((type)(val)&BITMASK_LEN(type, (bf_len))) << (bf_off);          \
    *(type*)(addr) = new_val;                                                  \
  }

static void kill_and_wait(int pid, int* status)
{
  kill(-pid, SIGKILL);
  kill(pid, SIGKILL);
  int i;
  for (i = 0; i < 100; i++) {
    if (waitpid(-1, status, WNOHANG | __WALL) == pid)
      return;
    usleep(1000);
  }
  DIR* dir = opendir("/sys/fs/fuse/connections");
  if (dir) {
    for (;;) {
      struct dirent* ent = readdir(dir);
      if (!ent)
        break;
      if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0)
        continue;
      char abort[300];
      snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort",
               ent->d_name);
      int fd = open(abort, O_WRONLY);
      if (fd == -1) {
        continue;
      }
      if (write(fd, abort, 1) < 0) {
      }
      close(fd);
    }
    closedir(dir);
  } else {
  }
  while (waitpid(-1, status, __WALL) != pid) {
  }
}

#define SYZ_HAVE_SETUP_TEST 1
static void setup_test()
{
  prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
  setpgrp();
}

#define SYZ_HAVE_RESET_TEST 1
static void reset_test()
{
  int fd;
  for (fd = 3; fd < 30; fd++)
    close(fd);
}

static void execute_one(void);

#define WAIT_FLAGS __WALL

static void loop(void)
{
  int iter;
  for (iter = 0;; iter++) {
    int pid = fork();
    if (pid < 0)
      exit(1);
    if (pid == 0) {
      setup_test();
      execute_one();
      reset_test();
      exit(0);
    }
    int status = 0;
    uint64_t start = current_time_ms();
    for (;;) {
      if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid)
        break;
      sleep_ms(1);
      if (current_time_ms() - start < 5 * 1000)
        continue;
      kill_and_wait(pid, &status);
      break;
    }
  }
}

void execute_one(void)
{
  *(uint32_t*)0x20000180 = 2;
  *(uint32_t*)0x20000184 = 0x70;
  *(uint8_t*)0x20000188 = 0x87;
  *(uint8_t*)0x20000189 = 0;
  *(uint8_t*)0x2000018a = 0;
  *(uint8_t*)0x2000018b = 0;
  *(uint32_t*)0x2000018c = 0;
  *(uint64_t*)0x20000190 = 0;
  *(uint64_t*)0x20000198 = 0;
  *(uint64_t*)0x200001a0 = 0;
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 0, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 1, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 2, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 3, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 4, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 5, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 6, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 7, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 8, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 9, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 10, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 11, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 12, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 13, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 14, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 15, 2);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 17, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 18, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 19, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 20, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 21, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 22, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 23, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 24, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 25, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 26, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 27, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 28, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 29, 35);
  *(uint32_t*)0x200001b0 = 0;
  *(uint32_t*)0x200001b4 = 0;
  *(uint64_t*)0x200001b8 = 0;
  *(uint64_t*)0x200001c0 = 0;
  *(uint64_t*)0x200001c8 = 0;
  *(uint64_t*)0x200001d0 = 0;
  *(uint32_t*)0x200001d8 = 0;
  *(uint32_t*)0x200001dc = 0;
  *(uint64_t*)0x200001e0 = 0;
  *(uint32_t*)0x200001e8 = 0;
  *(uint16_t*)0x200001ec = 0;
  *(uint16_t*)0x200001ee = 0;
  syscall(__NR_perf_event_open, 0x20000180, 0, -1, -1, 0);
  *(uint32_t*)0x20000140 = 0x66;
  syscall(__NR_ioctl, -1, 0x2283, 0x20000140);
  *(uint32_t*)0x20000180 = 6;
  *(uint32_t*)0x20000184 = 0x70;
  *(uint8_t*)0x20000188 = 0x59;
  *(uint8_t*)0x20000189 = 0;
  *(uint8_t*)0x2000018a = 0;
  *(uint8_t*)0x2000018b = 0;
  *(uint32_t*)0x2000018c = 0;
  *(uint64_t*)0x20000190 = 0;
  *(uint64_t*)0x20000198 = 0;
  *(uint64_t*)0x200001a0 = 0;
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 0, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 1, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 2, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 3, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 4, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 5, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 6, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 7, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 8, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 9, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 10, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 11, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 12, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 13, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 14, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 15, 2);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 17, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 18, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 19, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 20, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 21, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 22, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 23, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 24, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 25, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 26, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 27, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 28, 1);
  STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 29, 35);
  *(uint32_t*)0x200001b0 = 0;
  *(uint32_t*)0x200001b4 = 0;
  *(uint64_t*)0x200001b8 = 0x20000140;
  *(uint64_t*)0x200001c0 = 0;
  *(uint64_t*)0x200001c8 = 0;
  *(uint64_t*)0x200001d0 = 0;
  *(uint32_t*)0x200001d8 = 0;
  *(uint32_t*)0x200001dc = 0;
  *(uint64_t*)0x200001e0 = 0;
  *(uint32_t*)0x200001e8 = 0;
  *(uint16_t*)0x200001ec = 0;
  *(uint16_t*)0x200001ee = 0;
  syscall(__NR_perf_event_open, 0x20000180, -1, 0, -1, 0);
}
int main(void)
{
  syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
  for (procid = 0; procid < 8; procid++) {
    if (fork() == 0) {
      loop();
    }
  }
  sleep(1000000);
  return 0;
}
Steven Rostedt <rostedt@goodmis.org> 于2018年10月3日周三 上午10:45写道:
>
> On Sat, 29 Sep 2018 17:22:13 +0800
> 王晓东 <wisedd@gmail.com> wrote:
>
> > Hi there,
> >
> > We would like to report a kernel stack corrupted problem we identified
> > in the perf_trace_rcu_dyntick function of tracing events subsystem.
> > And the problem was founded by syzkaller.  We has tested the PoC on
> > the lasted master branch of kernel(4.19.0-rc5+).
> >
> > The crash log generated with KASAN enabled:
> >
> > root@pc:~# ./perf_trace_rcu_dyntick
> > [  582.069938] Kernel panic - not syncing: stack-protector: Kernel
> > stack is corrupted in: perf_trace_rcu_dyntick+0x355/0x4f0
> > [  582.069938]
> > [  582.071341] CPU: 6 PID: 3417 Comm: perf_trace_rcu_ Not tainted 4.19.0-rc5+ #1
> > [  582.072134] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
> > BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
> > [  582.073103] Call Trace:
> > [  582.073364]  <IRQ>
> > [  582.073614]  dump_stack+0x8c/0xce
> > [  582.074039]  panic+0x1cb/0x3aa
> > [  582.074427]  ? refcount_error_report+0x296/0x296
> > [  582.075003]  ? timerqueue_del+0x71/0x130
> > [  582.075553]  ? perf_trace_rcu_dyntick+0x355/0x4f0
> > [  582.076063]  ? __stack_chk_fail+0x6/0x20
> > [  582.076763]  ? perf_trace_rcu_dyntick+0x355/0x4f0
> > [  582.077369]  __stack_chk_fail+0x1f/0x20
> > [  582.077877]  perf_trace_rcu_dyntick+0x355/0x4f0
> > [  582.078442]  ? rcu_gp_is_expedited+0xa0/0xa0
> > [  582.078993]  ? rcu_gp_is_expedited+0xa0/0xa0
> > [  582.079525]  ? check_preempt_curr+0x1c2/0x2a0
> > [  582.080059]  ? sched_clock_cpu+0x18/0x160
> > [  582.080551]  rcu_nmi_enter+0x1f0/0x2f0
> > [  582.081036]  ? rcu_gp_is_expedited+0xa0/0xa0
> > [  582.081507]  irq_enter+0xf/0x80
> > [  582.081914]  smp_apic_timer_interrupt+0x1b/0x2d0
> > [  582.082480]  apic_timer_interrupt+0xf/0x20
> > [  582.082984]  </IRQ>
> > [  582.083219] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50
> > [  582.087816] Code: e8 35 0b 20 00 48 8b 14 24 e9 fe fe ff ff 48 89
> > df e8 24 0b 20 00 e9 d9 fe ff ff 4c 89 e7 e8 17 0b 20 00 e9 ab fe ff
> > ff 90 90 <65> 48 8b 04 25 40 dd 01 00 65 8b 15 70 03 8f 63 81 e2 00 01
> > 1f 00
> > [  582.090289] RSP: 0018:ffff8800651bf9e0 EFLAGS: 00000206 ORIG_RAX:
> > ffffffffffffff13
> > [  582.091238] RAX: 0000000000000000 RBX: ffffffff9eed12a5 RCX: ffffffff9c6ca1b6
> > [  582.092873] RDX: 0000000000000005 RSI: ffffffff9ee31d71 RDI: ffffffff9eed12a4
> > [  582.093934] RBP: 0000000000000078 R08: ffffed000d38dfb2 R09: ffffed000d38dfb1
> > [  582.095102] R10: 000000007350a3ba R11: ffff880069c6fd8f R12: ffff8800651bfa6e
> > [  582.096444] R13: 0000000000000001 R14: dffffc0000000000 R15: 000000000000006a
> > [  582.097414]  ? kallsyms_expand_symbol.constprop.11+0x176/0x250
> > [  582.098518]  kallsyms_expand_symbol.constprop.11+0x12e/0x250
> > [  582.099707]  kallsyms_lookup_name+0xbe/0x1d0
> > [  582.100369]  ? kallsyms_on_each_symbol+0x210/0x210
> > [  582.101436]  ? snprintf+0xbd/0xf0
> > [  582.102029]  ? vsprintf+0x30/0x30
> > [  582.102805]  ? kasan_kmalloc+0xa9/0xd0
> > [  582.103489]  ? alloc_trace_kprobe+0x6c0/0x930
> > [  582.104073]  kprobe_on_func_entry+0x57/0xb0
>
> I'm curious to what kretprobe was used.
>
> -- Steve
>
> > [  582.105421]  register_kretprobe+0x89/0xc10
> > [  582.105930]  ? set_print_fmt+0x32/0xa0
> > [  582.106376]  __register_trace_kprobe.part.10+0x14e/0x2e0
> > [  582.106980]  create_local_trace_kprobe+0x29c/0x3f0
> > [  582.107487]  perf_kprobe_init+0x15f/0x210
> > [  582.107912]  perf_kprobe_event_init+0xc4/0x140
> > [  582.108377]  perf_try_init_event+0xcb/0x290
> > [  582.108817]  perf_event_alloc+0x1476/0x2020
> > [  582.109264]  ? find_get_context.isra.106+0x690/0x690
> > [  582.109922]  ? __alloc_fd+0x1a3/0x4e0
> > [  582.120002]  __do_sys_perf_event_open+0x222/0x1f40
> > [  582.123049]  ? avc_has_perm_noaudit+0x340/0x340
> > [  582.131226]  ? perf_event_set_output+0x5f0/0x5f0
> > [  582.134395]  ? handle_mm_fault+0x103/0x350
> > [  582.138102]  ? ksys_ioctl+0x61/0x90
> > [  582.140234]  do_syscall_64+0x9a/0x2c0
> > [  582.142674]  ? prepare_exit_to_usermode+0xbc/0x150
> > [  582.146856]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
> > [  582.151127] RIP: 0033:0x446159
> > [  582.152816] Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00
> > 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24
> > 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 5b 08 fc ff c3 66 2e 0f 1f 84 00 00
> > 00 00
> > [  582.167257] RSP: 002b:00007fffc2b023d8 EFLAGS: 00000246 ORIG_RAX:
> > 000000000000012a
> > [  582.171375] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000446159
> > [  582.175760] RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000020000180
> > [  582.176487] RBP: 00007fffc2b025b0 R08: 0000000000000000 R09: 0000000000000000
> > [  582.177189] R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000406e40
> > [  582.177898] R13: 0000000000406ed0 R14: 0000000000000000 R15: 0000000000000000
> > [  583.353322] Shutting down cpus with NMI
> > [  583.354285] Kernel Offset: 0x1b400000 from 0xffffffff81000000
> > (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
> > [  583.356743] Rebooting in 86400 seconds..
> >
> >
> > This bug could be easily reproduced by running the PoC(generated by
> > syzkaller, and transformed to C Source code).
> >
> > For any further information, please feel free to contact us at
> > wisedd@gmail.com. We would be more than happy to provide other
> > information of this problem.
>

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: rcu: Kernel stack is corrupted in: perf_trace_rcu_dyntick
  2018-10-17  8:45   ` Phy Bio
@ 2018-10-17 10:43     ` Paul E. McKenney
  0 siblings, 0 replies; 6+ messages in thread
From: Paul E. McKenney @ 2018-10-17 10:43 UTC (permalink / raw)
  To: Phy Bio; +Cc: rostedt, mingo, linux-kernel, mhiramat, peterz

On Wed, Oct 17, 2018 at 04:45:48PM +0800, Phy Bio wrote:
> I will be very happy, if the source code can help you analyze this problem.
> 
> The source code is in the following:
> 
> #define _GNU_SOURCE
> 
> #include <dirent.h>
> #include <endian.h>
> #include <errno.h>
> #include <fcntl.h>
> #include <signal.h>
> #include <stdint.h>
> #include <stdio.h>
> #include <stdlib.h>
> #include <string.h>
> #include <sys/prctl.h>
> #include <sys/stat.h>
> #include <sys/syscall.h>
> #include <sys/types.h>
> #include <sys/wait.h>
> #include <time.h>
> #include <unistd.h>
> 
> unsigned long long procid;
> 
> static void sleep_ms(uint64_t ms)
> {
>   usleep(ms * 1000);
> }
> 
> static uint64_t current_time_ms(void)
> {
>   struct timespec ts;
>   if (clock_gettime(CLOCK_MONOTONIC, &ts))
>     exit(1);
>   return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000;
> }
> 
> #define BITMASK_LEN(type, bf_len) (type)((1ull << (bf_len)) - 1)
> 
> #define BITMASK_LEN_OFF(type, bf_off, bf_len)                                  \
>   (type)(BITMASK_LEN(type, (bf_len)) << (bf_off))
> 
> #define STORE_BY_BITMASK(type, addr, val, bf_off, bf_len)                      \
>   if ((bf_off) == 0 && (bf_len) == 0) {                                        \
>     *(type*)(addr) = (type)(val);                                              \
>   } else {                                                                     \
>     type new_val = *(type*)(addr);                                             \
>     new_val &= ~BITMASK_LEN_OFF(type, (bf_off), (bf_len));                     \
>     new_val |= ((type)(val)&BITMASK_LEN(type, (bf_len))) << (bf_off);          \
>     *(type*)(addr) = new_val;                                                  \
>   }
> 
> static void kill_and_wait(int pid, int* status)
> {
>   kill(-pid, SIGKILL);
>   kill(pid, SIGKILL);
>   int i;
>   for (i = 0; i < 100; i++) {
>     if (waitpid(-1, status, WNOHANG | __WALL) == pid)
>       return;
>     usleep(1000);
>   }
>   DIR* dir = opendir("/sys/fs/fuse/connections");
>   if (dir) {
>     for (;;) {
>       struct dirent* ent = readdir(dir);
>       if (!ent)
>         break;
>       if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0)
>         continue;
>       char abort[300];
>       snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort",
>                ent->d_name);
>       int fd = open(abort, O_WRONLY);
>       if (fd == -1) {
>         continue;
>       }
>       if (write(fd, abort, 1) < 0) {
>       }
>       close(fd);
>     }
>     closedir(dir);
>   } else {
>   }
>   while (waitpid(-1, status, __WALL) != pid) {
>   }
> }
> 
> #define SYZ_HAVE_SETUP_TEST 1
> static void setup_test()
> {
>   prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
>   setpgrp();
> }
> 
> #define SYZ_HAVE_RESET_TEST 1
> static void reset_test()
> {
>   int fd;
>   for (fd = 3; fd < 30; fd++)
>     close(fd);
> }
> 
> static void execute_one(void);
> 
> #define WAIT_FLAGS __WALL
> 
> static void loop(void)
> {
>   int iter;
>   for (iter = 0;; iter++) {
>     int pid = fork();
>     if (pid < 0)
>       exit(1);
>     if (pid == 0) {
>       setup_test();
>       execute_one();
>       reset_test();
>       exit(0);
>     }
>     int status = 0;
>     uint64_t start = current_time_ms();
>     for (;;) {
>       if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid)
>         break;
>       sleep_ms(1);
>       if (current_time_ms() - start < 5 * 1000)
>         continue;
>       kill_and_wait(pid, &status);
>       break;
>     }
>   }
> }
> 
> void execute_one(void)
> {
>   *(uint32_t*)0x20000180 = 2;
>   *(uint32_t*)0x20000184 = 0x70;
>   *(uint8_t*)0x20000188 = 0x87;
>   *(uint8_t*)0x20000189 = 0;
>   *(uint8_t*)0x2000018a = 0;
>   *(uint8_t*)0x2000018b = 0;
>   *(uint32_t*)0x2000018c = 0;
>   *(uint64_t*)0x20000190 = 0;
>   *(uint64_t*)0x20000198 = 0;
>   *(uint64_t*)0x200001a0 = 0;
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 0, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 1, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 2, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 3, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 4, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 5, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 6, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 7, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 8, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 9, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 10, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 11, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 12, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 13, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 14, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 15, 2);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 17, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 18, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 19, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 20, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 21, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 22, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 23, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 24, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 25, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 26, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 27, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 28, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 29, 35);
>   *(uint32_t*)0x200001b0 = 0;
>   *(uint32_t*)0x200001b4 = 0;
>   *(uint64_t*)0x200001b8 = 0;
>   *(uint64_t*)0x200001c0 = 0;
>   *(uint64_t*)0x200001c8 = 0;
>   *(uint64_t*)0x200001d0 = 0;
>   *(uint32_t*)0x200001d8 = 0;
>   *(uint32_t*)0x200001dc = 0;
>   *(uint64_t*)0x200001e0 = 0;
>   *(uint32_t*)0x200001e8 = 0;
>   *(uint16_t*)0x200001ec = 0;
>   *(uint16_t*)0x200001ee = 0;
>   syscall(__NR_perf_event_open, 0x20000180, 0, -1, -1, 0);
>   *(uint32_t*)0x20000140 = 0x66;
>   syscall(__NR_ioctl, -1, 0x2283, 0x20000140);
>   *(uint32_t*)0x20000180 = 6;
>   *(uint32_t*)0x20000184 = 0x70;
>   *(uint8_t*)0x20000188 = 0x59;
>   *(uint8_t*)0x20000189 = 0;
>   *(uint8_t*)0x2000018a = 0;
>   *(uint8_t*)0x2000018b = 0;
>   *(uint32_t*)0x2000018c = 0;
>   *(uint64_t*)0x20000190 = 0;
>   *(uint64_t*)0x20000198 = 0;
>   *(uint64_t*)0x200001a0 = 0;
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 0, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 1, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 2, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 3, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 4, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 5, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 6, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 7, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 8, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 9, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 10, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 11, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 12, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 13, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 14, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 15, 2);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 17, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 18, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 19, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 20, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 21, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 22, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 23, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 24, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 25, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 26, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 27, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 28, 1);
>   STORE_BY_BITMASK(uint64_t, 0x200001a8, 0, 29, 35);
>   *(uint32_t*)0x200001b0 = 0;
>   *(uint32_t*)0x200001b4 = 0;
>   *(uint64_t*)0x200001b8 = 0x20000140;
>   *(uint64_t*)0x200001c0 = 0;
>   *(uint64_t*)0x200001c8 = 0;
>   *(uint64_t*)0x200001d0 = 0;
>   *(uint32_t*)0x200001d8 = 0;
>   *(uint32_t*)0x200001dc = 0;
>   *(uint64_t*)0x200001e0 = 0;
>   *(uint32_t*)0x200001e8 = 0;
>   *(uint16_t*)0x200001ec = 0;
>   *(uint16_t*)0x200001ee = 0;
>   syscall(__NR_perf_event_open, 0x20000180, -1, 0, -1, 0);
> }
> int main(void)
> {
>   syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
>   for (procid = 0; procid < 8; procid++) {
>     if (fork() == 0) {
>       loop();
>     }
>   }
>   sleep(1000000);
>   return 0;
> }

Does this problem ever happen without the kretprobe in place?

							Thanx, Paul

> Steven Rostedt <rostedt@goodmis.org> 于2018年10月3日周三 上午10:45写道:
> >
> > On Sat, 29 Sep 2018 17:22:13 +0800
> > 王晓东 <wisedd@gmail.com> wrote:
> >
> > > Hi there,
> > >
> > > We would like to report a kernel stack corrupted problem we identified
> > > in the perf_trace_rcu_dyntick function of tracing events subsystem.
> > > And the problem was founded by syzkaller.  We has tested the PoC on
> > > the lasted master branch of kernel(4.19.0-rc5+).
> > >
> > > The crash log generated with KASAN enabled:
> > >
> > > root@pc:~# ./perf_trace_rcu_dyntick
> > > [  582.069938] Kernel panic - not syncing: stack-protector: Kernel
> > > stack is corrupted in: perf_trace_rcu_dyntick+0x355/0x4f0
> > > [  582.069938]
> > > [  582.071341] CPU: 6 PID: 3417 Comm: perf_trace_rcu_ Not tainted 4.19.0-rc5+ #1
> > > [  582.072134] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
> > > BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
> > > [  582.073103] Call Trace:
> > > [  582.073364]  <IRQ>
> > > [  582.073614]  dump_stack+0x8c/0xce
> > > [  582.074039]  panic+0x1cb/0x3aa
> > > [  582.074427]  ? refcount_error_report+0x296/0x296
> > > [  582.075003]  ? timerqueue_del+0x71/0x130
> > > [  582.075553]  ? perf_trace_rcu_dyntick+0x355/0x4f0
> > > [  582.076063]  ? __stack_chk_fail+0x6/0x20
> > > [  582.076763]  ? perf_trace_rcu_dyntick+0x355/0x4f0
> > > [  582.077369]  __stack_chk_fail+0x1f/0x20
> > > [  582.077877]  perf_trace_rcu_dyntick+0x355/0x4f0
> > > [  582.078442]  ? rcu_gp_is_expedited+0xa0/0xa0
> > > [  582.078993]  ? rcu_gp_is_expedited+0xa0/0xa0
> > > [  582.079525]  ? check_preempt_curr+0x1c2/0x2a0
> > > [  582.080059]  ? sched_clock_cpu+0x18/0x160
> > > [  582.080551]  rcu_nmi_enter+0x1f0/0x2f0
> > > [  582.081036]  ? rcu_gp_is_expedited+0xa0/0xa0
> > > [  582.081507]  irq_enter+0xf/0x80
> > > [  582.081914]  smp_apic_timer_interrupt+0x1b/0x2d0
> > > [  582.082480]  apic_timer_interrupt+0xf/0x20
> > > [  582.082984]  </IRQ>
> > > [  582.083219] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50
> > > [  582.087816] Code: e8 35 0b 20 00 48 8b 14 24 e9 fe fe ff ff 48 89
> > > df e8 24 0b 20 00 e9 d9 fe ff ff 4c 89 e7 e8 17 0b 20 00 e9 ab fe ff
> > > ff 90 90 <65> 48 8b 04 25 40 dd 01 00 65 8b 15 70 03 8f 63 81 e2 00 01
> > > 1f 00
> > > [  582.090289] RSP: 0018:ffff8800651bf9e0 EFLAGS: 00000206 ORIG_RAX:
> > > ffffffffffffff13
> > > [  582.091238] RAX: 0000000000000000 RBX: ffffffff9eed12a5 RCX: ffffffff9c6ca1b6
> > > [  582.092873] RDX: 0000000000000005 RSI: ffffffff9ee31d71 RDI: ffffffff9eed12a4
> > > [  582.093934] RBP: 0000000000000078 R08: ffffed000d38dfb2 R09: ffffed000d38dfb1
> > > [  582.095102] R10: 000000007350a3ba R11: ffff880069c6fd8f R12: ffff8800651bfa6e
> > > [  582.096444] R13: 0000000000000001 R14: dffffc0000000000 R15: 000000000000006a
> > > [  582.097414]  ? kallsyms_expand_symbol.constprop.11+0x176/0x250
> > > [  582.098518]  kallsyms_expand_symbol.constprop.11+0x12e/0x250
> > > [  582.099707]  kallsyms_lookup_name+0xbe/0x1d0
> > > [  582.100369]  ? kallsyms_on_each_symbol+0x210/0x210
> > > [  582.101436]  ? snprintf+0xbd/0xf0
> > > [  582.102029]  ? vsprintf+0x30/0x30
> > > [  582.102805]  ? kasan_kmalloc+0xa9/0xd0
> > > [  582.103489]  ? alloc_trace_kprobe+0x6c0/0x930
> > > [  582.104073]  kprobe_on_func_entry+0x57/0xb0
> >
> > I'm curious to what kretprobe was used.
> >
> > -- Steve
> >
> > > [  582.105421]  register_kretprobe+0x89/0xc10
> > > [  582.105930]  ? set_print_fmt+0x32/0xa0
> > > [  582.106376]  __register_trace_kprobe.part.10+0x14e/0x2e0
> > > [  582.106980]  create_local_trace_kprobe+0x29c/0x3f0
> > > [  582.107487]  perf_kprobe_init+0x15f/0x210
> > > [  582.107912]  perf_kprobe_event_init+0xc4/0x140
> > > [  582.108377]  perf_try_init_event+0xcb/0x290
> > > [  582.108817]  perf_event_alloc+0x1476/0x2020
> > > [  582.109264]  ? find_get_context.isra.106+0x690/0x690
> > > [  582.109922]  ? __alloc_fd+0x1a3/0x4e0
> > > [  582.120002]  __do_sys_perf_event_open+0x222/0x1f40
> > > [  582.123049]  ? avc_has_perm_noaudit+0x340/0x340
> > > [  582.131226]  ? perf_event_set_output+0x5f0/0x5f0
> > > [  582.134395]  ? handle_mm_fault+0x103/0x350
> > > [  582.138102]  ? ksys_ioctl+0x61/0x90
> > > [  582.140234]  do_syscall_64+0x9a/0x2c0
> > > [  582.142674]  ? prepare_exit_to_usermode+0xbc/0x150
> > > [  582.146856]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
> > > [  582.151127] RIP: 0033:0x446159
> > > [  582.152816] Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00
> > > 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24
> > > 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 5b 08 fc ff c3 66 2e 0f 1f 84 00 00
> > > 00 00
> > > [  582.167257] RSP: 002b:00007fffc2b023d8 EFLAGS: 00000246 ORIG_RAX:
> > > 000000000000012a
> > > [  582.171375] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000446159
> > > [  582.175760] RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000020000180
> > > [  582.176487] RBP: 00007fffc2b025b0 R08: 0000000000000000 R09: 0000000000000000
> > > [  582.177189] R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000406e40
> > > [  582.177898] R13: 0000000000406ed0 R14: 0000000000000000 R15: 0000000000000000
> > > [  583.353322] Shutting down cpus with NMI
> > > [  583.354285] Kernel Offset: 0x1b400000 from 0xffffffff81000000
> > > (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
> > > [  583.356743] Rebooting in 86400 seconds..
> > >
> > >
> > > This bug could be easily reproduced by running the PoC(generated by
> > > syzkaller, and transformed to C Source code).
> > >
> > > For any further information, please feel free to contact us at
> > > wisedd@gmail.com. We would be more than happy to provide other
> > > information of this problem.
> >
> 


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: rcu: Kernel stack is corrupted in: perf_trace_rcu_dyntick
  2018-09-29  9:22 rcu: Kernel stack is corrupted in: perf_trace_rcu_dyntick 王晓东
  2018-10-03  2:45 ` Steven Rostedt
@ 2018-10-18  2:13 ` Steven Rostedt
  2018-10-22  2:03   ` Phy Bio
  1 sibling, 1 reply; 6+ messages in thread
From: Steven Rostedt @ 2018-10-18  2:13 UTC (permalink / raw)
  To: 王晓东; +Cc: mingo, linux-kernel, Peter Zijlstra

On Sat, 29 Sep 2018 17:22:13 +0800
王晓东 <wisedd@gmail.com> wrote:

> Hi there,
> 
> We would like to report a kernel stack corrupted problem we identified
> in the perf_trace_rcu_dyntick function of tracing events subsystem.
> And the problem was founded by syzkaller.  We has tested the PoC on
> the lasted master branch of kernel(4.19.0-rc5+).
> 
> The crash log generated with KASAN enabled:
> 
> root@pc:~# ./perf_trace_rcu_dyntick
> [  582.069938] Kernel panic - not syncing: stack-protector: Kernel
> stack is corrupted in: perf_trace_rcu_dyntick+0x355/0x4f0
> [  582.069938]
> [  582.071341] CPU: 6 PID: 3417 Comm: perf_trace_rcu_ Not tainted 4.19.0-rc5+ #1
> [  582.072134] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
> BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
> [  582.073103] Call Trace:
> [  582.073364]  <IRQ>
> [  582.073614]  dump_stack+0x8c/0xce
> [  582.074039]  panic+0x1cb/0x3aa
> [  582.074427]  ? refcount_error_report+0x296/0x296
> [  582.075003]  ? timerqueue_del+0x71/0x130
> [  582.075553]  ? perf_trace_rcu_dyntick+0x355/0x4f0
> [  582.076063]  ? __stack_chk_fail+0x6/0x20
> [  582.076763]  ? perf_trace_rcu_dyntick+0x355/0x4f0
> [  582.077369]  __stack_chk_fail+0x1f/0x20
> [  582.077877]  perf_trace_rcu_dyntick+0x355/0x4f0
> [  582.078442]  ? rcu_gp_is_expedited+0xa0/0xa0
> [  582.078993]  ? rcu_gp_is_expedited+0xa0/0xa0
> [  582.079525]  ? check_preempt_curr+0x1c2/0x2a0
> [  582.080059]  ? sched_clock_cpu+0x18/0x160
> [  582.080551]  rcu_nmi_enter+0x1f0/0x2f0
> [  582.081036]  ? rcu_gp_is_expedited+0xa0/0xa0
> [  582.081507]  irq_enter+0xf/0x80
> [  582.081914]  smp_apic_timer_interrupt+0x1b/0x2d0
> [  582.082480]  apic_timer_interrupt+0xf/0x20
> [  582.082984]  </IRQ>
> [  582.083219] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50
> [  582.087816] Code: e8 35 0b 20 00 48 8b 14 24 e9 fe fe ff ff 48 89
> df e8 24 0b 20 00 e9 d9 fe ff ff 4c 89 e7 e8 17 0b 20 00 e9 ab fe ff
> ff 90 90 <65> 48 8b 04 25 40 dd 01 00 65 8b 15 70 03 8f 63 81 e2 00 01
> 1f 00
> [  582.090289] RSP: 0018:ffff8800651bf9e0 EFLAGS: 00000206 ORIG_RAX:
> ffffffffffffff13
> [  582.091238] RAX: 0000000000000000 RBX: ffffffff9eed12a5 RCX: ffffffff9c6ca1b6
> [  582.092873] RDX: 0000000000000005 RSI: ffffffff9ee31d71 RDI: ffffffff9eed12a4
> [  582.093934] RBP: 0000000000000078 R08: ffffed000d38dfb2 R09: ffffed000d38dfb1
> [  582.095102] R10: 000000007350a3ba R11: ffff880069c6fd8f R12: ffff8800651bfa6e
> [  582.096444] R13: 0000000000000001 R14: dffffc0000000000 R15: 000000000000006a
> [  582.097414]  ? kallsyms_expand_symbol.constprop.11+0x176/0x250
> [  582.098518]  kallsyms_expand_symbol.constprop.11+0x12e/0x250
> [  582.099707]  kallsyms_lookup_name+0xbe/0x1d0
> [  582.100369]  ? kallsyms_on_each_symbol+0x210/0x210
> [  582.101436]  ? snprintf+0xbd/0xf0
> [  582.102029]  ? vsprintf+0x30/0x30
> [  582.102805]  ? kasan_kmalloc+0xa9/0xd0
> [  582.103489]  ? alloc_trace_kprobe+0x6c0/0x930
> [  582.104073]  kprobe_on_func_entry+0x57/0xb0
> [  582.105421]  register_kretprobe+0x89/0xc10
> [  582.105930]  ? set_print_fmt+0x32/0xa0
> [  582.106376]  __register_trace_kprobe.part.10+0x14e/0x2e0
> [  582.106980]  create_local_trace_kprobe+0x29c/0x3f0
> [  582.107487]  perf_kprobe_init+0x15f/0x210
> [  582.107912]  perf_kprobe_event_init+0xc4/0x140

I added Peter to the Cc, because he maintains perf.

I have no idea what's going on here with kretprobes? Non-root can have
kretprobes added to the kernel?

-- Steve


> [  582.108377]  perf_try_init_event+0xcb/0x290
> [  582.108817]  perf_event_alloc+0x1476/0x2020
> [  582.109264]  ? find_get_context.isra.106+0x690/0x690
> [  582.109922]  ? __alloc_fd+0x1a3/0x4e0
> [  582.120002]  __do_sys_perf_event_open+0x222/0x1f40
> [  582.123049]  ? avc_has_perm_noaudit+0x340/0x340
> [  582.131226]  ? perf_event_set_output+0x5f0/0x5f0
> [  582.134395]  ? handle_mm_fault+0x103/0x350
> [  582.138102]  ? ksys_ioctl+0x61/0x90
> [  582.140234]  do_syscall_64+0x9a/0x2c0
> [  582.142674]  ? prepare_exit_to_usermode+0xbc/0x150
> [  582.146856]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
> [  582.151127] RIP: 0033:0x446159
> [  582.152816] Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00
> 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24
> 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 5b 08 fc ff c3 66 2e 0f 1f 84 00 00
> 00 00
> [  582.167257] RSP: 002b:00007fffc2b023d8 EFLAGS: 00000246 ORIG_RAX:
> 000000000000012a
> [  582.171375] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000446159
> [  582.175760] RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000020000180
> [  582.176487] RBP: 00007fffc2b025b0 R08: 0000000000000000 R09: 0000000000000000
> [  582.177189] R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000406e40
> [  582.177898] R13: 0000000000406ed0 R14: 0000000000000000 R15: 0000000000000000
> [  583.353322] Shutting down cpus with NMI
> [  583.354285] Kernel Offset: 0x1b400000 from 0xffffffff81000000
> (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
> [  583.356743] Rebooting in 86400 seconds..
> 
> 
> This bug could be easily reproduced by running the PoC(generated by
> syzkaller, and transformed to C Source code).
> 
> For any further information, please feel free to contact us at
> wisedd@gmail.com. We would be more than happy to provide other
> information of this problem.


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: rcu: Kernel stack is corrupted in: perf_trace_rcu_dyntick
  2018-10-18  2:13 ` Steven Rostedt
@ 2018-10-22  2:03   ` Phy Bio
  0 siblings, 0 replies; 6+ messages in thread
From: Phy Bio @ 2018-10-22  2:03 UTC (permalink / raw)
  To: rostedt; +Cc: mingo, linux-kernel, peterz

This PoC generated by syzkaller needs ROOT permission to run.
Steven Rostedt <rostedt@goodmis.org> 于2018年10月18日周四 上午10:13写道:
>
> On Sat, 29 Sep 2018 17:22:13 +0800
> 王晓东 <wisedd@gmail.com> wrote:
>
> > Hi there,
> >
> > We would like to report a kernel stack corrupted problem we identified
> > in the perf_trace_rcu_dyntick function of tracing events subsystem.
> > And the problem was founded by syzkaller.  We has tested the PoC on
> > the lasted master branch of kernel(4.19.0-rc5+).
> >
> > The crash log generated with KASAN enabled:
> >
> > root@pc:~# ./perf_trace_rcu_dyntick
> > [  582.069938] Kernel panic - not syncing: stack-protector: Kernel
> > stack is corrupted in: perf_trace_rcu_dyntick+0x355/0x4f0
> > [  582.069938]
> > [  582.071341] CPU: 6 PID: 3417 Comm: perf_trace_rcu_ Not tainted 4.19.0-rc5+ #1
> > [  582.072134] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
> > BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
> > [  582.073103] Call Trace:
> > [  582.073364]  <IRQ>
> > [  582.073614]  dump_stack+0x8c/0xce
> > [  582.074039]  panic+0x1cb/0x3aa
> > [  582.074427]  ? refcount_error_report+0x296/0x296
> > [  582.075003]  ? timerqueue_del+0x71/0x130
> > [  582.075553]  ? perf_trace_rcu_dyntick+0x355/0x4f0
> > [  582.076063]  ? __stack_chk_fail+0x6/0x20
> > [  582.076763]  ? perf_trace_rcu_dyntick+0x355/0x4f0
> > [  582.077369]  __stack_chk_fail+0x1f/0x20
> > [  582.077877]  perf_trace_rcu_dyntick+0x355/0x4f0
> > [  582.078442]  ? rcu_gp_is_expedited+0xa0/0xa0
> > [  582.078993]  ? rcu_gp_is_expedited+0xa0/0xa0
> > [  582.079525]  ? check_preempt_curr+0x1c2/0x2a0
> > [  582.080059]  ? sched_clock_cpu+0x18/0x160
> > [  582.080551]  rcu_nmi_enter+0x1f0/0x2f0
> > [  582.081036]  ? rcu_gp_is_expedited+0xa0/0xa0
> > [  582.081507]  irq_enter+0xf/0x80
> > [  582.081914]  smp_apic_timer_interrupt+0x1b/0x2d0
> > [  582.082480]  apic_timer_interrupt+0xf/0x20
> > [  582.082984]  </IRQ>
> > [  582.083219] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50
> > [  582.087816] Code: e8 35 0b 20 00 48 8b 14 24 e9 fe fe ff ff 48 89
> > df e8 24 0b 20 00 e9 d9 fe ff ff 4c 89 e7 e8 17 0b 20 00 e9 ab fe ff
> > ff 90 90 <65> 48 8b 04 25 40 dd 01 00 65 8b 15 70 03 8f 63 81 e2 00 01
> > 1f 00
> > [  582.090289] RSP: 0018:ffff8800651bf9e0 EFLAGS: 00000206 ORIG_RAX:
> > ffffffffffffff13
> > [  582.091238] RAX: 0000000000000000 RBX: ffffffff9eed12a5 RCX: ffffffff9c6ca1b6
> > [  582.092873] RDX: 0000000000000005 RSI: ffffffff9ee31d71 RDI: ffffffff9eed12a4
> > [  582.093934] RBP: 0000000000000078 R08: ffffed000d38dfb2 R09: ffffed000d38dfb1
> > [  582.095102] R10: 000000007350a3ba R11: ffff880069c6fd8f R12: ffff8800651bfa6e
> > [  582.096444] R13: 0000000000000001 R14: dffffc0000000000 R15: 000000000000006a
> > [  582.097414]  ? kallsyms_expand_symbol.constprop.11+0x176/0x250
> > [  582.098518]  kallsyms_expand_symbol.constprop.11+0x12e/0x250
> > [  582.099707]  kallsyms_lookup_name+0xbe/0x1d0
> > [  582.100369]  ? kallsyms_on_each_symbol+0x210/0x210
> > [  582.101436]  ? snprintf+0xbd/0xf0
> > [  582.102029]  ? vsprintf+0x30/0x30
> > [  582.102805]  ? kasan_kmalloc+0xa9/0xd0
> > [  582.103489]  ? alloc_trace_kprobe+0x6c0/0x930
> > [  582.104073]  kprobe_on_func_entry+0x57/0xb0
> > [  582.105421]  register_kretprobe+0x89/0xc10
> > [  582.105930]  ? set_print_fmt+0x32/0xa0
> > [  582.106376]  __register_trace_kprobe.part.10+0x14e/0x2e0
> > [  582.106980]  create_local_trace_kprobe+0x29c/0x3f0
> > [  582.107487]  perf_kprobe_init+0x15f/0x210
> > [  582.107912]  perf_kprobe_event_init+0xc4/0x140
>
> I added Peter to the Cc, because he maintains perf.
>
> I have no idea what's going on here with kretprobes? Non-root can have
> kretprobes added to the kernel?
>
> -- Steve
>
>
> > [  582.108377]  perf_try_init_event+0xcb/0x290
> > [  582.108817]  perf_event_alloc+0x1476/0x2020
> > [  582.109264]  ? find_get_context.isra.106+0x690/0x690
> > [  582.109922]  ? __alloc_fd+0x1a3/0x4e0
> > [  582.120002]  __do_sys_perf_event_open+0x222/0x1f40
> > [  582.123049]  ? avc_has_perm_noaudit+0x340/0x340
> > [  582.131226]  ? perf_event_set_output+0x5f0/0x5f0
> > [  582.134395]  ? handle_mm_fault+0x103/0x350
> > [  582.138102]  ? ksys_ioctl+0x61/0x90
> > [  582.140234]  do_syscall_64+0x9a/0x2c0
> > [  582.142674]  ? prepare_exit_to_usermode+0xbc/0x150
> > [  582.146856]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
> > [  582.151127] RIP: 0033:0x446159
> > [  582.152816] Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00
> > 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24
> > 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 5b 08 fc ff c3 66 2e 0f 1f 84 00 00
> > 00 00
> > [  582.167257] RSP: 002b:00007fffc2b023d8 EFLAGS: 00000246 ORIG_RAX:
> > 000000000000012a
> > [  582.171375] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000446159
> > [  582.175760] RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000020000180
> > [  582.176487] RBP: 00007fffc2b025b0 R08: 0000000000000000 R09: 0000000000000000
> > [  582.177189] R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000406e40
> > [  582.177898] R13: 0000000000406ed0 R14: 0000000000000000 R15: 0000000000000000
> > [  583.353322] Shutting down cpus with NMI
> > [  583.354285] Kernel Offset: 0x1b400000 from 0xffffffff81000000
> > (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
> > [  583.356743] Rebooting in 86400 seconds..
> >
> >
> > This bug could be easily reproduced by running the PoC(generated by
> > syzkaller, and transformed to C Source code).
> >
> > For any further information, please feel free to contact us at
> > wisedd@gmail.com. We would be more than happy to provide other
> > information of this problem.
>

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2018-10-22  2:02 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-09-29  9:22 rcu: Kernel stack is corrupted in: perf_trace_rcu_dyntick 王晓东
2018-10-03  2:45 ` Steven Rostedt
2018-10-17  8:45   ` Phy Bio
2018-10-17 10:43     ` Paul E. McKenney
2018-10-18  2:13 ` Steven Rostedt
2018-10-22  2:03   ` Phy Bio

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