================================================================== BUG: KASAN: use-after-free in batadv_interface_tx+0x1194/0x1880 net/batman-adv/soft-interface.c:226 Read of size 2 at addr ffff8880a5c7eacb by task syz-executor1/19590 CPU: 1 PID: 19590 Comm: syz-executor1 Not tainted 5.0.0-rc3+ #24 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:4385 [inline] netdev_start_xmit include/linux/netdevice.h:4394 [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_sendto+0x387/0x5f0 net/socket.c:1788 __do_sys_sendto net/socket.c:1800 [inline] __se_sys_sendto net/socket.c:1796 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1796 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:00007fdb46acac78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000458089 RDX: 0000000000000012 RSI: 00000000200001c0 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fdb46acb6d4 R13: 00000000004c56f0 R14: 00000000004d94c0 R15: 00000000ffffffff Allocated by task 9158: 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 mempool_alloc_slab+0x47/0x60 mm/mempool.c:505 mempool_alloc+0x19f/0x500 mm/mempool.c:385 bio_alloc_bioset+0x3c1/0x720 block/bio.c:489 bio_alloc include/linux/bio.h:393 [inline] submit_bh_wbc+0x133/0x7f0 fs/buffer.c:3061 __block_write_full_page+0x91a/0x1480 fs/buffer.c:1765 block_write_full_page+0x21f/0x270 fs/buffer.c:2955 blkdev_writepage+0x25/0x30 fs/block_dev.c:604 __writepage+0x67/0xe0 mm/page-writeback.c:2296 write_cache_pages+0xbec/0x1ce0 mm/page-writeback.c:2231 generic_writepages+0xed/0x160 mm/page-writeback.c:2320 blkdev_writepages+0x1e/0x30 fs/block_dev.c:1988 do_writepages+0x99/0x1a0 mm/page-writeback.c:2335 __writeback_single_inode+0x1c5/0x1620 fs/fs-writeback.c:1316 writeback_sb_inodes+0x762/0x1260 fs/fs-writeback.c:1580 __writeback_inodes_wb+0x16d/0x3d0 fs/fs-writeback.c:1649 wb_writeback+0xa2d/0xf70 fs/fs-writeback.c:1758 wb_check_start_all fs/fs-writeback.c:1882 [inline] wb_do_writeback fs/fs-writeback.c:1908 [inline] wb_workfn+0xe52/0x16f0 fs/fs-writeback.c:1942 process_one_work+0xd0c/0x1ce0 kernel/workqueue.c:2153 worker_thread+0x143/0x14a0 kernel/workqueue.c:2296 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Freed by task 16: 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 mempool_free_slab+0x1e/0x30 mm/mempool.c:512 mempool_free+0xed/0x380 mm/mempool.c:494 bio_free+0x324/0x570 block/bio.c:267 bio_put+0x17a/0x1f0 block/bio.c:561 end_bio_bh_io_sync+0xfb/0x140 fs/buffer.c:2981 bio_endio+0x840/0xfb0 block/bio.c:1793 req_bio_endio block/blk-core.c:196 [inline] blk_update_request+0x3dd/0xd10 block/blk-core.c:1454 scsi_end_request+0xf2/0xb70 drivers/scsi/scsi_lib.c:587 scsi_io_completion+0x263/0x1bb0 drivers/scsi/scsi_lib.c:993 scsi_finish_command+0x527/0x910 drivers/scsi/scsi.c:248 scsi_softirq_done+0x45d/0x520 drivers/scsi/scsi_lib.c:1499 blk_done_softirq+0x4ab/0x750 block/blk-softirq.c:37 __do_softirq+0x30b/0xb11 kernel/softirq.c:292 The buggy address belongs to the object at ffff8880a5c7eac0 which belongs to the cache bio-0 of size 200 The buggy address is located 11 bytes inside of 200-byte region [ffff8880a5c7eac0, ffff8880a5c7eb88) The buggy address belongs to the page: page:ffffea0002971f80 count:1 mapcount:0 mapping:ffff88821b732900 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00026ebec8 ffffea000248eec8 ffff88821b732900 raw: 0000000000000000 ffff8880a5c7e0c0 000000010000000c 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a5c7e980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a5c7ea00: fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc >ffff8880a5c7ea80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ^ ffff8880a5c7eb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a5c7eb80: fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================