On Fri, Mar 3, 2017 at 2:11 AM, Dmitry Vyukov <dvyu...@google.com> wrote: > Also like this one: > > ================================================================== > BUG: KASAN: use-after-free in atomic_long_read > include/linux/compiler.h:254 [inline] at addr ffff8800538aba60 > BUG: KASAN: use-after-free in get_work_pool+0x2f2/0x340 > kernel/workqueue.c:709 at addr ffff8800538aba60 > Read of size 8 by task syz-executor6/7965 > CPU: 2 PID: 7965 Comm: syz-executor6 Not tainted 4.10.0+ #248 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:15 [inline] > dump_stack+0x2ee/0x3ef lib/dump_stack.c:51 > kasan_object_err+0x1c/0x70 mm/kasan/report.c:166 > print_address_description mm/kasan/report.c:204 [inline] > kasan_report_error mm/kasan/report.c:288 [inline] > kasan_report.part.2+0x198/0x440 mm/kasan/report.c:310 > kasan_report mm/kasan/report.c:331 [inline] > __asan_report_load8_noabort+0x29/0x30 mm/kasan/report.c:331 > atomic_long_read include/linux/compiler.h:254 [inline] > get_work_pool+0x2f2/0x340 kernel/workqueue.c:709 > __queue_work+0x2b3/0x1210 kernel/workqueue.c:1401 > queue_work_on+0x2e9/0x330 kernel/workqueue.c:1486 > queue_work include/linux/workqueue.h:487 [inline] > strp_check_rcv+0x25/0x30 net/strparser/strparser.c:494
It is not kcm_wq, it is strp_wq, and the work struct is strp->rx_work which lives in struct kcm_psock. The work is cancelled by strp_done(), it seems get queued again after strp_done()... > kcm_attach net/kcm/kcmsock.c:1434 [inline] > kcm_attach_ioctl net/kcm/kcmsock.c:1455 [inline] > kcm_ioctl+0x8bb/0x1800 net/kcm/kcmsock.c:1690 > sock_do_ioctl+0x65/0xb0 net/socket.c:895 > sock_ioctl+0x2c2/0x440 net/socket.c:993 > vfs_ioctl fs/ioctl.c:43 [inline] > do_vfs_ioctl+0x1bf/0x1790 fs/ioctl.c:683 > SYSC_ioctl fs/ioctl.c:698 [inline] > SyS_ioctl+0x8f/0xc0 fs/ioctl.c:689 > entry_SYSCALL_64_fastpath+0x1f/0xc2 > RIP: 0033:0x4458d9 > RSP: 002b:00007f1dce9d1b58 EFLAGS: 00000286 ORIG_RAX: 0000000000000010 > RAX: ffffffffffffffda RBX: 0000000000000024 RCX: 00000000004458d9 > RDX: 0000000020b68000 RSI: 00000000000089e0 RDI: 0000000000000024 > RBP: 00000000006e0220 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000286 R12: 00000000007080a8 > R13: 0000000000000000 R14: 00007f1dce9d29c0 R15: 00007f1dce9d2700 > Object at ffff8800538ab940, in cache kcm_psock_cache size: 616 > Allocated: > PID = 7965 > save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57 > save_stack+0x43/0xd0 mm/kasan/kasan.c:502 > set_track mm/kasan/kasan.c:514 [inline] > kasan_kmalloc+0xaa/0xd0 mm/kasan/kasan.c:605 > kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:544 > kmem_cache_alloc+0x102/0x680 mm/slab.c:3571 > kmem_cache_zalloc include/linux/slab.h:653 [inline] > kcm_attach net/kcm/kcmsock.c:1384 [inline] > kcm_attach_ioctl net/kcm/kcmsock.c:1455 [inline] > kcm_ioctl+0x303/0x1800 net/kcm/kcmsock.c:1690 > sock_do_ioctl+0x65/0xb0 net/socket.c:895 > sock_ioctl+0x2c2/0x440 net/socket.c:993 > vfs_ioctl fs/ioctl.c:43 [inline] > do_vfs_ioctl+0x1bf/0x1790 fs/ioctl.c:683 > SYSC_ioctl fs/ioctl.c:698 [inline] > SyS_ioctl+0x8f/0xc0 fs/ioctl.c:689 > entry_SYSCALL_64_fastpath+0x1f/0xc2 > Freed: > PID = 7982 > save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57 > save_stack+0x43/0xd0 mm/kasan/kasan.c:502 > set_track mm/kasan/kasan.c:514 [inline] > kasan_slab_free+0x6f/0xb0 mm/kasan/kasan.c:578 > __cache_free mm/slab.c:3513 [inline] > kmem_cache_free+0x71/0x240 mm/slab.c:3773 > kcm_unattach+0xee7/0x1520 net/kcm/kcmsock.c:1558 > kcm_unattach_ioctl net/kcm/kcmsock.c:1603 [inline] > kcm_ioctl+0xfae/0x1800 net/kcm/kcmsock.c:1700 > sock_do_ioctl+0x65/0xb0 net/socket.c:895 > sock_ioctl+0x2c2/0x440 net/socket.c:993 > vfs_ioctl fs/ioctl.c:43 [inline] > do_vfs_ioctl+0x1bf/0x1790 fs/ioctl.c:683 > SYSC_ioctl fs/ioctl.c:698 [inline] > SyS_ioctl+0x8f/0xc0 fs/ioctl.c:689 > entry_SYSCALL_64_fastpath+0x1f/0xc2 > Memory state around the buggy address: > ffff8800538ab900: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb > ffff8800538ab980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >>ffff8800538aba00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ^ > ffff8800538aba80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8800538abb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ==================================================================
