================================================================== BUG: KASAN: use-after-free in batadv_interface_tx+0x1194/0x1880 net/batman-adv/soft-interface.c:226 Read of size 2 at addr ffff88808aa3a80b by task syz-executor3/5298 CPU: 0 PID: 5298 Comm: syz-executor3 Not tainted 5.0.0-rc4+ #51 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+0x1db/0x2d0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 __asan_report_load_n_noabort+0xf/0x20 mm/kasan/generic_report.c:145 batadv_interface_tx+0x1194/0x1880 net/batman-adv/soft-interface.c:226 __netdev_start_xmit include/linux/netdevice.h:4382 [inline] netdev_start_xmit include/linux/netdevice.h:4391 [inline] dev_direct_xmit+0x368/0x670 net/core/dev.c:3930 packet_direct_xmit+0xfb/0x170 net/packet/af_packet.c:246 packet_snd net/packet/af_packet.c:2933 [inline] packet_sendmsg+0x27fb/0x6920 net/packet/af_packet.c:2958 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xdd/0x130 net/socket.c:631 ___sys_sendmsg+0x409/0x910 net/socket.c:2116 __sys_sendmmsg+0x246/0x730 net/socket.c:2211 __do_sys_sendmmsg net/socket.c:2240 [inline] __se_sys_sendmmsg net/socket.c:2237 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2237 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458089 Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffb34db5c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000458089 RDX: 0000000000000001 RSI: 0000000020008a80 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffb34db66d4 R13: 00000000004c4fe0 R14: 00000000004d8ba8 R15: 00000000ffffffff Allocated by task 13493: save_stack+0x45/0xd0 mm/kasan/common.c:73 set_track mm/kasan/common.c:85 [inline] __kasan_kmalloc mm/kasan/common.c:496 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:469 kasan_kmalloc mm/kasan/common.c:504 [inline] kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:411 kmem_cache_alloc+0x12d/0x710 mm/slab.c:3543 kmem_cache_zalloc include/linux/slab.h:730 [inline] __alloc_file+0x93/0x480 fs/file_table.c:100 alloc_empty_file+0x72/0x170 fs/file_table.c:150 alloc_file+0x5e/0x4d0 fs/file_table.c:192 alloc_file_pseudo+0x24a/0x3b0 fs/file_table.c:231 sock_alloc_file+0x4d/0x170 net/socket.c:394 sock_map_fd net/socket.c:417 [inline] __sys_socket+0x172/0x260 net/socket.c:1351 __do_sys_socket net/socket.c:1356 [inline] __se_sys_socket net/socket.c:1354 [inline] __x64_sys_socket+0x73/0xb0 net/socket.c:1354 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 7797: save_stack+0x45/0xd0 mm/kasan/common.c:73 set_track mm/kasan/common.c:85 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:458 kasan_slab_free+0xe/0x10 mm/kasan/common.c:466 __cache_free mm/slab.c:3487 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3749 file_free_rcu+0x98/0xe0 fs/file_table.c:49 __rcu_reclaim kernel/rcu/rcu.h:240 [inline] rcu_do_batch kernel/rcu/tree.c:2452 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2773 [inline] rcu_process_callbacks+0xc4a/0x1680 kernel/rcu/tree.c:2754 __do_softirq+0x30b/0xb11 kernel/softirq.c:292 The buggy address belongs to the object at ffff88808aa3a780 which belongs to the cache filp(91:syz4) of size 456 The buggy address is located 139 bytes inside of 456-byte region [ffff88808aa3a780, ffff88808aa3a948) The buggy address belongs to the page: page:ffffea00022a8e80 count:1 mapcount:0 mapping:ffff888093f21480 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea0002a21508 ffffea0002422bc8 ffff888093f21480 raw: 0000000000000000 ffff88808aa3a000 0000000100000006 ffff88808e498ac0 page dumped because: kasan: bad access detected page->mem_cgroup:ffff88808e498ac0 Memory state around the buggy address: ffff88808aa3a700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88808aa3a780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88808aa3a800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88808aa3a880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88808aa3a900: fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc ==================================================================