On 2018-08-03 04:46 AM, Wanlong Gao wrote:
Hi Martinand all folks,
Recently we find a kernel panic with memory corruption caused by SG_IO ioctl(),
and it can be easily reproduced by running following reproducer about
minutes,any idea?
Which kernel?
And what are the underlying devices (e.g. does /dev/sg0 refer to a SATA disk,
a real SCSI disk (SAS for example), USB mass storage, etc)?
Also can you get a copy of the kernel panic?
Doug Gilbert
C reproducer:
// autogenerated by syzkaller (http://github.com/google/syzkaller)
#define _GNU_SOURCE
#include <endian.h>
#include <sys/syscall.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <stdint.h>
#include <string.h>
static uintptr_t syz_open_dev(uintptr_t a0, uintptr_t a1, uintptr_t a2)
{
if (a0 == 0xc || a0 == 0xb) {
char buf[128];
sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1,
(uint8_t)a2);
return open(buf, O_RDWR, 0);
} else {
char buf[1024];
char* hash;
strncpy(buf, (char*)a0, sizeof(buf) - 1);
buf[sizeof(buf) - 1] = 0;
while ((hash = strchr(buf, '#'))) {
*hash = '0' + (char)(a1 % 10);
a1 /= 10;
}
return open(buf, a2, 0);
}
}
static void execute_one();
extern unsigned long long procid;
void loop()
{
while (1) {
execute_one();
}
}
uint64_t r[1] = {0xffffffffffffffff};
void execute_one()
{
long res = 0;
memcpy((void*)0x20000040, "/dev/sg#", 9);
res = syz_open_dev(0x20000040, 0, 0);
if (res != -1)
r[0] = res;
*(uint32_t*)0x200002c0 = 0x53;
*(uint32_t*)0x200002c4 = 0;
*(uint8_t*)0x200002c8 = 0xd;
*(uint8_t*)0x200002c9 = 0;
*(uint16_t*)0x200002ca = 0;
*(uint32_t*)0x200002cc = 0x95;
*(uint64_t*)0x200002d0 = 0x20000080;
*(uint64_t*)0x200002d8 = 0x20000000;
memcpy((void*)0x20000000,
"\x08\xf0\xa8\x77\xd3\xbe\x87\x5d\xda\x65\x79\x3f\xc7", 13);
*(uint64_t*)0x200002e0 = 0x20000180;
*(uint32_t*)0x200002e8 = 0x8001;
*(uint32_t*)0x200002ec = 0x10024;
*(uint32_t*)0x200002f0 = -1;
*(uint64_t*)0x200002f4 = 0x20000280;
*(uint8_t*)0x200002fc = 0;
*(uint8_t*)0x200002fd = 0;
*(uint8_t*)0x200002fe = 0;
*(uint8_t*)0x200002ff = 0;
*(uint16_t*)0x20000300 = 0;
*(uint16_t*)0x20000302 = 0;
*(uint32_t*)0x20000304 = 0;
*(uint32_t*)0x20000308 = 0;
*(uint32_t*)0x2000030c = 0;
syscall(__NR_ioctl, r[0], 0x2285, 0x200002c0);
}
int main()
{
syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
for (;;) {
loop();
}
}
