tmpfs: No value for mount option 'dont_hash' ================================================================== BUG: KASAN: use-after-free in tasklet_action+0x29f/0x340 kernel/softirq.c:506 Read of size 8 at addr ffff88809fb2b2d0 by task syz-executor.1/28558 CPU: 0 PID: 28558 Comm: syz-executor.1 Not tainted 4.14.213-syzkaller #0 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+0x1b2/0x283 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x194 mm/kasan/report.c:351 kasan_report mm/kasan/report.c:409 [inline] __asan_report_load8_noabort+0x68/0x70 mm/kasan/report.c:430 tasklet_action+0x29f/0x340 kernel/softirq.c:506 __do_softirq+0x254/0xa1d kernel/softirq.c:288 invoke_softirq kernel/softirq.c:368 [inline] irq_exit+0x193/0x240 kernel/softirq.c:409 exiting_irq arch/x86/include/asm/apic.h:648 [inline] smp_apic_timer_interrupt+0x141/0x5e0 arch/x86/kernel/apic/apic.c:1102 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:793 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779 [inline] RIP: 0010:lock_acquire+0x1ec/0x3f0 kernel/locking/lockdep.c:4001 RSP: 0018:ffff88822d017c58 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff10 RAX: 1ffffffff11e1251 RBX: ffff8880a2a90600 RCX: ffff88822d017b60 RDX: dffffc0000000000 RSI: ffffffff8bca7f60 RDI: 0000000000000286 RBP: ffffffff89043f98 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000002 R11: ffff8880a2a90600 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001 __raw_write_lock include/linux/rwlock_api_smp.h:210 [inline] _raw_write_lock+0x2a/0x40 kernel/locking/spinlock.c:296 remove_proc_entry+0x6b/0x230 fs/proc/generic.c:549 bcm_release+0x424/0x6c0 net/can/bcm.c:1573 __sock_release+0xcd/0x2b0 net/socket.c:602 sock_close+0x15/0x20 net/socket.c:1139 __fput+0x25f/0x7a0 fs/file_table.c:210 task_work_run+0x11f/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x417b71 RSP: 002b:00007ffcd1d40ad0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000417b71 RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000004 RBP: 0000000000000001 R08: 0000000000000256 R09: 0000000054bb625a R10: 00007ffcd1d40bb0 R11: 0000000000000293 R12: ffffffffffffffff R13: 0000000000056de8 R14: 00000000000003e8 R15: 000000000119bf8c Allocated by task 28565: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551 kmem_cache_alloc_trace+0x131/0x3d0 mm/slab.c:3618 kmalloc include/linux/slab.h:488 [inline] kzalloc include/linux/slab.h:661 [inline] bcm_tx_setup net/can/bcm.c:952 [inline] bcm_sendmsg+0x2029/0x3a10 net/can/bcm.c:1388 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 ___sys_sendmsg+0x6c8/0x800 net/socket.c:2062 __sys_sendmsg+0xa3/0x120 net/socket.c:2096 SYSC_sendmsg net/socket.c:2107 [inline] SyS_sendmsg+0x27/0x40 net/socket.c:2103 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 28558: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xc9/0x250 mm/slab.c:3815 bcm_release+0xff/0x6c0 net/can/bcm.c:1540 __sock_release+0xcd/0x2b0 net/socket.c:602 sock_close+0x15/0x20 net/socket.c:1139 __fput+0x25f/0x7a0 fs/file_table.c:210 task_work_run+0x11f/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb The buggy address belongs to the object at ffff88809fb2b200 which belongs to the cache kmalloc-1024 of size 1024 The buggy address is located 208 bytes inside of 1024-byte region [ffff88809fb2b200, ffff88809fb2b600) The buggy address belongs to the page: page:ffffea00027eca80 count:1 mapcount:0 mapping:ffff88809fb2a000 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffff88809fb2a000 0000000000000000 0000000100000007 raw: ffffea00026746a0 ffffea000296a720 ffff88813fe80ac0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809fb2b180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809fb2b200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88809fb2b280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88809fb2b300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809fb2b380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================