vcan0: j1939_tp_rxtimer: 0x00000000ca70701d: rx timeout, send abort ================================================================== BUG: KASAN: use-after-free in atomic_sub_return include/asm-generic/atomic-instrumented.h:159 [inline] BUG: KASAN: use-after-free in atomic_dec_return include/linux/atomic-fallback.h:455 [inline] BUG: KASAN: use-after-free in j1939_sock_pending_del+0x26/0x80 net/can/j1939/socket.c:73 Write of size 4 at addr ffff88808f0a84c0 by task syz-executor.2/9235 CPU: 1 PID: 9235 Comm: syz-executor.2 Not tainted 5.4.0-rc6+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:634 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192 __kasan_check_write+0x14/0x20 mm/kasan/common.c:98 atomic_sub_return include/asm-generic/atomic-instrumented.h:159 [inline] atomic_dec_return include/linux/atomic-fallback.h:455 [inline] j1939_sock_pending_del+0x26/0x80 net/can/j1939/socket.c:73 __j1939_session_drop net/can/j1939/transport.c:257 [inline] j1939_session_destroy net/can/j1939/transport.c:270 [inline] __j1939_session_release net/can/j1939/transport.c:280 [inline] kref_put include/linux/kref.h:65 [inline] j1939_session_put+0x107/0x180 net/can/j1939/transport.c:285 j1939_tp_rxtimer+0x26e/0x27b net/can/j1939/transport.c:1177 __run_hrtimer kernel/time/hrtimer.c:1514 [inline] __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1576 hrtimer_run_softirq+0x17e/0x270 kernel/time/hrtimer.c:1593 __do_softirq+0x262/0x98c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1137 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 RIP: 0010:__unwind_start+0x6/0x3d0 arch/x86/kernel/unwind_frame.c:368 Code: 75 0f 8b 17 31 c0 85 d2 74 05 e8 a5 f5 ff ff c9 c3 48 89 7d f8 e8 ba 45 7c 00 48 8b 7d f8 eb e2 0f 1f 40 00 55 48 89 e5 41 57 <49> 89 ff 41 56 41 55 49 89 f5 31 f6 41 54 49 89 d4 ba 60 00 00 00 RSP: 0018:ffff88808f857650 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: ffff8880a89ec440 RBX: ffffffff81622f30 RCX: ffff88808f8576f0 RDX: 0000000000000000 RSI: ffff8880a89ec440 RDI: ffff88808f857668 RBP: ffff88808f857658 R08: 1ffffffff14f0d44 R09: ffffed101319ea00 R10: fffffbfff14f0d44 R11: ffffffff8a786a27 R12: ffff88808f857720 R13: 0000000000000000 R14: ffff8880a89ec440 R15: ffff8880aa402000 unwind_start arch/x86/include/asm/unwind.h:60 [inline] arch_stack_walk+0x5e/0xf0 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0xac/0xe0 kernel/stacktrace.c:123 save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc mm/kasan/common.c:510 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:483 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:518 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc mm/slab.c:3319 [inline] __do_kmalloc mm/slab.c:3653 [inline] __kmalloc+0x14c/0x770 mm/slab.c:3664 kmalloc include/linux/slab.h:561 [inline] tomoyo_realpath_from_path+0xcd/0x7b0 security/tomoyo/realpath.c:277 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x230/0x430 security/tomoyo/file.c:822 tomoyo_path_symlink+0xaa/0xf0 security/tomoyo/tomoyo.c:206 security_path_symlink+0x10a/0x170 security/security.c:1053 do_symlinkat+0x137/0x290 fs/namei.c:4144 __do_sys_symlink fs/namei.c:4165 [inline] __se_sys_symlink fs/namei.c:4163 [inline] __x64_sys_symlink+0x59/0x80 fs/namei.c:4163 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459f47 Code: 0f 1f 00 b8 5c 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 6d b9 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 58 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 4d b9 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffe50ed6d68 EFLAGS: 00000202 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000459f47 RDX: 00007ffe50ed6e03 RSI: 00000000004bfc7e RDI: 00007ffe50ed6df0 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000013 R10: 0000000000000075 R11: 0000000000000202 R12: 0000000000000001 R13: 00007ffe50ed6da0 R14: 0000000000000000 R15: 00007ffe50ed6db0 Allocated by task 9215: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc mm/kasan/common.c:510 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:483 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:524 __do_kmalloc mm/slab.c:3655 [inline] __kmalloc+0x163/0x770 mm/slab.c:3664 kmalloc include/linux/slab.h:561 [inline] sk_prot_alloc+0x23a/0x310 net/core/sock.c:1603 sk_alloc+0x39/0xf70 net/core/sock.c:1657 can_create+0x1e7/0x4b0 net/can/af_can.c:157 __sock_create+0x3d8/0x730 net/socket.c:1418 sock_create net/socket.c:1469 [inline] __sys_socket+0x103/0x220 net/socket.c:1511 __do_sys_socket net/socket.c:1520 [inline] __se_sys_socket net/socket.c:1518 [inline] __x64_sys_socket+0x73/0xb0 net/socket.c:1518 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 9235: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] kasan_set_free_info mm/kasan/common.c:332 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:471 kasan_slab_free+0xe/0x10 mm/kasan/common.c:480 __cache_free mm/slab.c:3425 [inline] kfree+0x10a/0x2c0 mm/slab.c:3756 sk_prot_free net/core/sock.c:1640 [inline] __sk_destruct+0x4aa/0x680 net/core/sock.c:1724 sk_destruct+0xd5/0x110 net/core/sock.c:1739 __sk_free+0xfb/0x360 net/core/sock.c:1750 sock_wfree+0xed/0x190 net/core/sock.c:1966 skb_release_head_state+0xeb/0x260 net/core/skbuff.c:652 skb_release_all+0x16/0x60 net/core/skbuff.c:663 __kfree_skb net/core/skbuff.c:679 [inline] kfree_skb net/core/skbuff.c:697 [inline] kfree_skb+0x101/0x3c0 net/core/skbuff.c:691 skb_queue_purge+0x19/0x40 net/core/skbuff.c:3078 j1939_session_destroy net/can/j1939/transport.c:269 [inline] __j1939_session_release net/can/j1939/transport.c:280 [inline] kref_put include/linux/kref.h:65 [inline] j1939_session_put+0x97/0x180 net/can/j1939/transport.c:285 j1939_tp_rxtimer+0x26e/0x27b net/can/j1939/transport.c:1177 __run_hrtimer kernel/time/hrtimer.c:1514 [inline] __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1576 hrtimer_run_softirq+0x17e/0x270 kernel/time/hrtimer.c:1593 __do_softirq+0x262/0x98c kernel/softirq.c:292 The buggy address belongs to the object at ffff88808f0a8000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1216 bytes inside of 2048-byte region [ffff88808f0a8000, ffff88808f0a8800) The buggy address belongs to the page: page:ffffea00023c2a00 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea000238bc88 ffffea0001a787c8 ffff8880aa400e00 raw: 0000000000000000 ffff88808f0a8000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88808f0a8380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88808f0a8400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88808f0a8480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88808f0a8500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88808f0a8580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================