On Mon, Oct 12, 2015 at 1:41 PM, Vlastimil Babka <vbabka@xxxxxxx> wrote: > On 10/12/2015 11:55 AM, Dmitry Vyukov wrote: >> >> Hello, >> >> The following program crashes kernel: >> >> // autogenerated by syzkaller (http://github.com/google/syzkaller) >> #include <syscall.h> >> #include <string.h> >> #include <stdint.h> >> >> int main() >> { >> long r0 = syscall(SYS_shmget, 0x0ul, 0x2ul, 0x8ul); >> long r1 = syscall(SYS_shmat, r0, 0x20000000ul, 0x0ul); >> long r2 = syscall(SYS_mremap, 0x20000000ul, 0x1000ul, >> 0x3000ul, 0x3ul, 0x207f9000ul); >> long r19 = syscall(SYS_shmctl, r0, 0x0ul, 0); >> long r20 = syscall(SYS_remap_file_pages, 0x207f9000ul, >> 0x3000ul, 0x0ul, 0x7ul, 0x0ul); >> return 0; >> } >> >> On commit dd36d7393d6310b0c1adefb22fba79c3cf8a577c >> (git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git) >> >> ------------[ cut here ]------------ >> WARNING: CPU: 2 PID: 2636 at ipc/shm.c:162 shm_open+0x74/0x80() >> Modules linked in: >> CPU: 2 PID: 2636 Comm: a.out Not tainted 4.3.0-rc3+ #37 >> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs >> 01/01/2011 >> ffffffff81bcb43c ffff88081bf0bd70 ffffffff812fe8d6 0000000000000000 >> ffff88081bf0bda8 ffffffff81051ff1 ffffffffffffffea ffff88081b896ca8 >> ffff880819b81620 ffff8800bbaa6d00 ffff880819b81600 ffff88081bf0bdb8 >> Call Trace: >> [< inline >] __dump_stack lib/dump_stack.c:15 >> [<ffffffff812fe8d6>] dump_stack+0x44/0x5e lib/dump_stack.c:50 >> [<ffffffff81051ff1>] warn_slowpath_common+0x81/0xc0 kernel/panic.c:447 >> [<ffffffff810520e5>] warn_slowpath_null+0x15/0x20 kernel/panic.c:480 >> [< inline >] shm_lock ipc/shm.c:162 >> [<ffffffff81295c64>] shm_open+0x74/0x80 ipc/shm.c:196 >> [<ffffffff81295cbe>] shm_mmap+0x4e/0x80 ipc/shm.c:399 (discriminator 2) >> [<ffffffff81142d14>] mmap_region+0x3c4/0x5e0 mm/mmap.c:1627 >> [<ffffffff81143227>] do_mmap+0x2f7/0x3d0 mm/mmap.c:1402 >> [< inline >] do_mmap_pgoff include/linux/mm.h:1930 >> [< inline >] SYSC_remap_file_pages mm/mmap.c:2694 > > > Hmm what kind of stack unwinder catches inlines? Some external patch, based > on debuginfo? We use the following script to symbolize kernel stack traces. It adds file:line info and inlined frames. https://github.com/google/sanitizers/blob/master/address-sanitizer/tools/kasan_symbolize.py -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>