On Mon, Jan 8, 2018 at 12:43 PM, syzbot <syzbot+40396d275b34b0dd5...@syzkaller.appspotmail.com> wrote: > Hello, > > syzkaller hit the following crash on > f66faae2f80a45feafc04ce63ef744ac4b6e8c05 > git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git/master > compiler: gcc (GCC) 7.1.1 20170620 > .config is attached > Raw console output is attached. > Unfortunately, I don't have any reproducer for this bug yet. > > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+40396d275b34b0dd5...@syzkaller.appspotmail.com > It will help syzbot understand when the bug is fixed. See footer for > details. > If you forward the report, please keep this part and the footer.
This looks like an issue in kcm sockets, so +kcm maintainers. > device ip6_vti0 entered promiscuous mode > ================================================================== > BUG: KASAN: use-after-free in constant_test_bit > arch/x86/include/asm/bitops.h:325 [inline] > BUG: KASAN: use-after-free in work_is_static_object+0x39/0x40 > kernel/workqueue.c:443 > Read of size 8 at addr ffff8801beca5788 by task syz-executor2/12922 > > CPU: 0 PID: 12922 Comm: syz-executor2 Not tainted 4.15.0-rc5+ #178 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:17 [inline] > dump_stack+0x194/0x257 lib/dump_stack.c:53 > print_address_description+0x73/0x250 mm/kasan/report.c:252 > kasan_report_error mm/kasan/report.c:351 [inline] > kasan_report+0x25b/0x340 mm/kasan/report.c:409 > __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430 > constant_test_bit arch/x86/include/asm/bitops.h:325 [inline] > work_is_static_object+0x39/0x40 kernel/workqueue.c:443 > debug_object_activate+0x36f/0x730 lib/debugobjects.c:470 > debug_work_activate kernel/workqueue.c:492 [inline] > __queue_work+0x163/0x1230 kernel/workqueue.c:1381 > queue_work_on+0x16a/0x1c0 kernel/workqueue.c:1487 > queue_work include/linux/workqueue.h:488 [inline] > strp_check_rcv+0x25/0x30 net/strparser/strparser.c:552 > kcm_attach net/kcm/kcmsock.c:1439 [inline] > kcm_attach_ioctl net/kcm/kcmsock.c:1460 [inline] > kcm_ioctl+0x82f/0x1690 net/kcm/kcmsock.c:1665 > sock_do_ioctl+0x65/0xb0 net/socket.c:956 > sock_ioctl+0x2c2/0x440 net/socket.c:1053 > vfs_ioctl fs/ioctl.c:46 [inline] > do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686 > SYSC_ioctl fs/ioctl.c:701 [inline] > SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 > entry_SYSCALL_64_fastpath+0x23/0x9a > RIP: 0033:0x452ac9 > RSP: 002b:00007f1bbd860c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000010 > RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452ac9 > RDX: 0000000020954ff8 RSI: 00000000000089e0 RDI: 0000000000000017 > RBP: 000000000000057b R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f6428 > R13: 00000000ffffffff R14: 00007f1bbd8616d4 R15: 0000000000000000 > > Allocated by task 12922: > save_stack+0x43/0xd0 mm/kasan/kasan.c:447 > set_track mm/kasan/kasan.c:459 [inline] > kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 > kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489 > kmem_cache_alloc+0x12e/0x760 mm/slab.c:3544 > kmem_cache_zalloc include/linux/slab.h:678 [inline] > kcm_attach net/kcm/kcmsock.c:1394 [inline] > kcm_attach_ioctl net/kcm/kcmsock.c:1460 [inline] > kcm_ioctl+0x2d2/0x1690 net/kcm/kcmsock.c:1665 > sock_do_ioctl+0x65/0xb0 net/socket.c:956 > sock_ioctl+0x2c2/0x440 net/socket.c:1053 > vfs_ioctl fs/ioctl.c:46 [inline] > do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686 > SYSC_ioctl fs/ioctl.c:701 [inline] > SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 > entry_SYSCALL_64_fastpath+0x23/0x9a > > Freed by task 12929: > save_stack+0x43/0xd0 mm/kasan/kasan.c:447 > set_track mm/kasan/kasan.c:459 [inline] > kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 > __cache_free mm/slab.c:3488 [inline] > kmem_cache_free+0x83/0x2a0 mm/slab.c:3746 > kcm_unattach+0xe53/0x1510 net/kcm/kcmsock.c:1563 > kcm_unattach_ioctl net/kcm/kcmsock.c:1608 [inline] > kcm_ioctl+0xe54/0x1690 net/kcm/kcmsock.c:1675 > sock_do_ioctl+0x65/0xb0 net/socket.c:956 > sock_ioctl+0x2c2/0x440 net/socket.c:1053 > vfs_ioctl fs/ioctl.c:46 [inline] > do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686 > SYSC_ioctl fs/ioctl.c:701 [inline] > SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 > entry_SYSCALL_64_fastpath+0x23/0x9a > > The buggy address belongs to the object at ffff8801beca56c0 > which belongs to the cache kcm_psock_cache of size 544 > The buggy address is located 200 bytes inside of > 544-byte region [ffff8801beca56c0, ffff8801beca58e0) > The buggy address belongs to the page: > page:000000005180a80a count:1 mapcount:0 mapping:0000000058aa9a5c index:0x0 > compound_mapcount: 0 > flags: 0x2fffc0000008100(slab|head) > raw: 02fffc0000008100 ffff8801beca40c0 0000000000000000 000000010000000b > raw: ffff8801d31e8a48 ffff8801d31e8a48 ffff8801d3f6a380 0000000000000000 > page dumped because: kasan: bad access detected > > Memory state around the buggy address: > ffff8801beca5680: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb > ffff8801beca5700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >> >> ffff8801beca5780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ^ > ffff8801beca5800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8801beca5880: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc > ================================================================== > > > --- > This bug is generated by a dumb bot. It may contain errors. > See https://goo.gl/tpsmEJ for details. > Direct all questions to syzkal...@googlegroups.com. > > syzbot will keep track of this bug report. > If you forgot to add the Reported-by tag, once the fix for this bug is > merged > into any tree, please reply to this email with: > #syz fix: exact-commit-title > To mark this as a duplicate of another syzbot report, please reply with: > #syz dup: exact-subject-of-another-report > If it's a one-off invalid bug report, please reply with: > #syz invalid > Note: if the crash happens again, it will cause creation of a new bug > report. > Note: all commands must start from beginning of the line in the email body. > > -- > You received this message because you are subscribed to the Google Groups > "syzkaller-bugs" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to syzkaller-bugs+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/syzkaller-bugs/001a1144d6e8ef29870562424c44%40google.com. > For more options, visit https://groups.google.com/d/optout.
