================================================================== BUG: KASAN: use-after-free in tasklet_action+0x29f/0x340 syzkaller/managers/linux-4-14/kernel/kernel/softirq.c:506 Read of size 8 at addr ffff88804584e9d0 by task syz-executor.0/1018 CPU: 1 PID: 1018 Comm: syz-executor.0 Not tainted 4.14.218-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack syzkaller/managers/linux-4-14/kernel/lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 syzkaller/managers/linux-4-14/kernel/lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 syzkaller/managers/linux-4-14/kernel/mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x191 syzkaller/managers/linux-4-14/kernel/mm/kasan/report.c:351 kasan_report syzkaller/managers/linux-4-14/kernel/mm/kasan/report.c:409 [inline] __asan_report_load8_noabort+0x68/0x70 syzkaller/managers/linux-4-14/kernel/mm/kasan/report.c:430 tasklet_action+0x29f/0x340 syzkaller/managers/linux-4-14/kernel/kernel/softirq.c:506 __do_softirq+0x24d/0x9ff syzkaller/managers/linux-4-14/kernel/kernel/softirq.c:288 do_softirq_own_stack+0x2a/0x40 syzkaller/managers/linux-4-14/kernel/arch/x86/entry/entry_64.S:1016 do_softirq.part.0+0x154/0x1b0 syzkaller/managers/linux-4-14/kernel/kernel/softirq.c:332 do_softirq syzkaller/managers/linux-4-14/kernel/kernel/softirq.c:324 [inline] __local_bh_enable_ip+0x12b/0x170 syzkaller/managers/linux-4-14/kernel/kernel/softirq.c:185 sock_orphan syzkaller/managers/linux-4-14/kernel/./include/net/sock.h:1715 [inline] bcm_release+0x524/0x6c0 syzkaller/managers/linux-4-14/kernel/net/can/bcm.c:1582 __sock_release+0xcd/0x2b0 syzkaller/managers/linux-4-14/kernel/net/socket.c:602 sock_close+0x15/0x20 syzkaller/managers/linux-4-14/kernel/net/socket.c:1139 __fput+0x25f/0x7a0 syzkaller/managers/linux-4-14/kernel/fs/file_table.c:210 task_work_run+0x11f/0x190 syzkaller/managers/linux-4-14/kernel/kernel/task_work.c:113 tracehook_notify_resume syzkaller/managers/linux-4-14/kernel/./include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1ad/0x200 syzkaller/managers/linux-4-14/kernel/arch/x86/entry/common.c:164 prepare_exit_to_usermode syzkaller/managers/linux-4-14/kernel/arch/x86/entry/common.c:199 [inline] syscall_return_slowpath syzkaller/managers/linux-4-14/kernel/arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 syzkaller/managers/linux-4-14/kernel/arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x418e1b RSP: 002b:00007ffde0fad3c0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000007 RCX: 0000000000418e1b RDX: 0000000000000000 RSI: 0000000000572198 RDI: 0000000000000006 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000001b3062d5f4 R10: 00007ffde0fad4b0 R11: 0000000000000293 R12: 00000000000003e8 R13: 00000000000ae5fa R14: 000000000056bf60 R15: 000000000056bf60 Allocated by task 1028: save_stack syzkaller/managers/linux-4-14/kernel/mm/kasan/kasan.c:447 [inline] set_track syzkaller/managers/linux-4-14/kernel/mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xeb/0x160 syzkaller/managers/linux-4-14/kernel/mm/kasan/kasan.c:551 kmem_cache_alloc_trace+0x131/0x3d0 syzkaller/managers/linux-4-14/kernel/mm/slab.c:3618 kmalloc syzkaller/managers/linux-4-14/kernel/./include/linux/slab.h:488 [inline] kzalloc syzkaller/managers/linux-4-14/kernel/./include/linux/slab.h:661 [inline] bcm_tx_setup syzkaller/managers/linux-4-14/kernel/net/can/bcm.c:952 [inline] bcm_sendmsg+0x2029/0x3a10 syzkaller/managers/linux-4-14/kernel/net/can/bcm.c:1388 sock_sendmsg_nosec syzkaller/managers/linux-4-14/kernel/net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 syzkaller/managers/linux-4-14/kernel/net/socket.c:656 ___sys_sendmsg+0x6c8/0x800 syzkaller/managers/linux-4-14/kernel/net/socket.c:2062 __sys_sendmsg+0xa3/0x120 syzkaller/managers/linux-4-14/kernel/net/socket.c:2096 SYSC_sendmsg syzkaller/managers/linux-4-14/kernel/net/socket.c:2107 [inline] SyS_sendmsg+0x27/0x40 syzkaller/managers/linux-4-14/kernel/net/socket.c:2103 do_syscall_64+0x1d5/0x640 syzkaller/managers/linux-4-14/kernel/arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 1018: save_stack syzkaller/managers/linux-4-14/kernel/mm/kasan/kasan.c:447 [inline] set_track syzkaller/managers/linux-4-14/kernel/mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xc3/0x1a0 syzkaller/managers/linux-4-14/kernel/mm/kasan/kasan.c:524 __cache_free syzkaller/managers/linux-4-14/kernel/mm/slab.c:3496 [inline] kfree+0xc9/0x250 syzkaller/managers/linux-4-14/kernel/mm/slab.c:3815 bcm_release+0xff/0x6c0 syzkaller/managers/linux-4-14/kernel/net/can/bcm.c:1540 __sock_release+0xcd/0x2b0 syzkaller/managers/linux-4-14/kernel/net/socket.c:602 sock_close+0x15/0x20 syzkaller/managers/linux-4-14/kernel/net/socket.c:1139 __fput+0x25f/0x7a0 syzkaller/managers/linux-4-14/kernel/fs/file_table.c:210 task_work_run+0x11f/0x190 syzkaller/managers/linux-4-14/kernel/kernel/task_work.c:113 tracehook_notify_resume syzkaller/managers/linux-4-14/kernel/./include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1ad/0x200 syzkaller/managers/linux-4-14/kernel/arch/x86/entry/common.c:164 prepare_exit_to_usermode syzkaller/managers/linux-4-14/kernel/arch/x86/entry/common.c:199 [inline] syscall_return_slowpath syzkaller/managers/linux-4-14/kernel/arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 syzkaller/managers/linux-4-14/kernel/arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb The buggy address belongs to the object at ffff88804584e900 which belongs to the cache kmalloc-1024 of size 1024 The buggy address is located 208 bytes inside of 1024-byte region [ffff88804584e900, ffff88804584ed00) The buggy address belongs to the page: page:ffffea0001161380 count:1 mapcount:0 mapping:ffff88804584e000 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffff88804584e000 0000000000000000 0000000100000007 raw: ffffea0002a96220 ffffea00012eb320 ffff88813fe80ac0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88804584e880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88804584e900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88804584e980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88804584ea00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804584ea80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ieee80211 phy2720: hwaddr 02:00:00:0a:a0:00 registered ==================================================================