================================================================== BUG: KASAN: use-after-free in __read_once_size include/linux/compiler.h:185 [inline] BUG: KASAN: use-after-free in dev_queue_xmit_nit+0x7b5/0x950 net/core/dev.c:1925 Read of size 8 at addr ffff8880a0518ba8 by task syz-executor.5/12621 CPU: 0 PID: 12621 Comm: syz-executor.5 Not tainted 4.14.256-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+0x1b2/0x281 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351 kasan_report mm/kasan/report.c:409 [inline] __asan_report_load8_noabort+0x68/0x70 mm/kasan/report.c:430 __read_once_size include/linux/compiler.h:185 [inline] dev_queue_xmit_nit+0x7b5/0x950 net/core/dev.c:1925 xmit_one net/core/dev.c:3001 [inline] dev_hard_start_xmit+0xaa/0x890 net/core/dev.c:3021 __dev_queue_xmit+0x1d7f/0x2480 net/core/dev.c:3521 neigh_hh_output include/net/neighbour.h:490 [inline] neigh_output include/net/neighbour.h:498 [inline] ip6_finish_output2+0xc6a/0x1f10 net/ipv6/ip6_output.c:120 ip6_finish_output+0x5c6/0xd50 net/ipv6/ip6_output.c:192 NF_HOOK_COND include/linux/netfilter.h:239 [inline] ip6_output+0x1c5/0x660 net/ipv6/ip6_output.c:209 dst_output include/net/dst.h:470 [inline] NF_HOOK include/linux/netfilter.h:250 [inline] mld_sendpack+0x5fe/0xea0 net/ipv6/mcast.c:1657 mld_send_cr net/ipv6/mcast.c:1953 [inline] mld_ifc_timer_expire+0x57c/0xcd0 net/ipv6/mcast.c:2452 call_timer_fn+0x14a/0x650 kernel/time/timer.c:1280 expire_timers+0x232/0x4d0 kernel/time/timer.c:1319 __run_timers kernel/time/timer.c:1637 [inline] run_timer_softirq+0x1d5/0x5a0 kernel/time/timer.c:1650 __do_softirq+0x24d/0x9ff 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:638 [inline] smp_apic_timer_interrupt+0x141/0x5e0 arch/x86/kernel/apic/apic.c:1106 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:rcu_read_unlock_special+0x452/0xdd0 kernel/rcu/tree_plugin.h:542 RSP: 0018:ffff8880a375f518 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff10 RAX: 1ffffffff11e1279 RBX: ffff8880a1f661c0 RCX: 1ffff110143ecd57 RDX: dffffc0000000000 RSI: ffff8880a1f66ac0 RDI: 0000000000000286 RBP: ffff8880a1f66544 R08: ffff8880ba534cb0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000286 R13: ffff8880a1f66546 R14: ffff8880a1f66545 R15: 0000000000000000 __rcu_read_unlock+0x158/0x160 kernel/rcu/update.c:260 rcu_read_unlock include/linux/rcupdate.h:684 [inline] ext4_get_group_desc+0x193/0x430 fs/ext4/balloc.c:294 __ext4_get_inode_loc+0x178/0xf30 fs/ext4/inode.c:4515 ext4_get_inode_loc fs/ext4/inode.c:4641 [inline] ext4_reserve_inode_write+0xd9/0x230 fs/ext4/inode.c:5802 ext4_mark_inode_dirty+0x12f/0x7a0 fs/ext4/inode.c:5969 ext4_dirty_inode+0x6c/0x90 fs/ext4/inode.c:6008 __mark_inode_dirty+0x11e/0xf40 fs/fs-writeback.c:2131 mark_inode_dirty include/linux/fs.h:2024 [inline] dquot_alloc_space include/linux/quotaops.h:315 [inline] dquot_alloc_block include/linux/quotaops.h:332 [inline] ext4_mb_new_blocks+0x4c6/0x3db0 fs/ext4/mballoc.c:4562 ext4_ext_map_blocks+0x2845/0x6b10 fs/ext4/extents.c:4505 ext4_map_blocks+0x675/0x1730 fs/ext4/inode.c:656 ext4_alloc_file_blocks.isra.0+0x24e/0x840 fs/ext4/extents.c:4732 ext4_fallocate+0x713/0x1d80 fs/ext4/extents.c:5014 vfs_fallocate+0x346/0x790 fs/open.c:319 SYSC_fallocate fs/open.c:342 [inline] SyS_fallocate+0x4a/0x80 fs/open.c:336 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f8b79e94af9 RSP: 002b:00007f8b78e0a188 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f8b79fa7f60 RCX: 00007f8b79e94af9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00007f8b79eeeff7 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000008020001 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc85f6c89f R14: 00007f8b78e0a300 R15: 0000000000022000 Allocated by task 12611: 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 __do_kmalloc mm/slab.c:3720 [inline] __kmalloc+0x15a/0x400 mm/slab.c:3729 kmalloc include/linux/slab.h:493 [inline] sk_prot_alloc+0x1ba/0x290 net/core/sock.c:1484 sk_alloc+0x36/0xcd0 net/core/sock.c:1538 packet_create+0xf5/0x7f0 net/packet/af_packet.c:3295 __sock_create+0x303/0x620 net/socket.c:1275 sock_create net/socket.c:1315 [inline] SYSC_socket net/socket.c:1345 [inline] SyS_socket+0xd1/0x1b0 net/socket.c:1325 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 12611: 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 sk_prot_free net/core/sock.c:1521 [inline] __sk_destruct+0x5e3/0x760 net/core/sock.c:1600 sk_destruct net/core/sock.c:1615 [inline] __sk_free+0xd9/0x2d0 net/core/sock.c:1623 sk_free+0x2b/0x40 net/core/sock.c:1634 sock_put include/net/sock.h:1664 [inline] packet_release+0x837/0xa80 net/packet/af_packet.c:3124 __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 ffff8880a0518380 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 2088 bytes inside of 4096-byte region [ffff8880a0518380, ffff8880a0519380) The buggy address belongs to the page: page:ffffea0002814600 count:1 mapcount:0 mapping:ffff8880a0518380 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffff8880a0518380 0000000000000000 0000000100000001 raw: ffffea0002766ba0 ffffea000281f2a0 ffff88813fe74dc0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a0518a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a0518b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880a0518b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a0518c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a0518c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================