================================================================== BUG: KASAN: use-after-free in batadv_interface_tx+0x1194/0x1880 net/batman-adv/soft-interface.c:226 Read of size 2 at addr ffff8880a91645cb by task syz-executor2/28687 CPU: 0 PID: 28687 Comm: syz-executor2 Not tainted 4.20.0+ #3 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:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report mm/kasan/report.c:412 [inline] kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:396 __asan_report_load_n_noabort+0xf/0x20 mm/kasan/report.c:443 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:2932 [inline] packet_sendmsg+0x2753/0x6830 net/packet/af_packet.c:2957 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: 0033:0x457ec9 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:00007f159376fc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457ec9 RDX: 000000000000004c RSI: 0000000020000180 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f15937706d4 R13: 00000000004c53f5 R14: 00000000004d8ef0 R15: 00000000ffffffff Allocated by task 28528: save_stack+0x45/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc mm/kasan/kasan.c:553 [inline] kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:531 __do_kmalloc mm/slab.c:3722 [inline] __kmalloc+0x15d/0x750 mm/slab.c:3731 kmalloc include/linux/slab.h:551 [inline] sock_kmalloc net/core/sock.c:1992 [inline] sock_kmalloc+0x166/0x200 net/core/sock.c:1983 af_alg_alloc_areq+0x7c/0x300 crypto/af_alg.c:1097 _aead_recvmsg crypto/algif_aead.c:157 [inline] aead_recvmsg+0x49d/0x1b40 crypto/algif_aead.c:334 sock_recvmsg_nosec net/socket.c:794 [inline] sock_recvmsg net/socket.c:801 [inline] sock_recvmsg+0xd0/0x110 net/socket.c:797 sock_read_iter+0x3ba/0x5a0 net/socket.c:878 call_read_iter include/linux/fs.h:1851 [inline] do_iter_readv_writev+0x6f4/0xae0 fs/read_write.c:678 do_iter_read+0x268/0x650 fs/read_write.c:922 vfs_readv+0x175/0x1c0 fs/read_write.c:986 do_readv+0x11a/0x300 fs/read_write.c:1019 __do_sys_readv fs/read_write.c:1106 [inline] __se_sys_readv fs/read_write.c:1103 [inline] __x64_sys_readv+0x75/0xb0 fs/read_write.c:1103 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 28528: save_stack+0x45/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3817 __sock_kfree_s net/core/sock.c:2013 [inline] sock_kfree_s+0x29/0x70 net/core/sock.c:2019 af_alg_free_resources+0x71/0x90 crypto/af_alg.c:1033 _aead_recvmsg crypto/algif_aead.c:321 [inline] aead_recvmsg+0x979/0x1b40 crypto/algif_aead.c:334 sock_recvmsg_nosec net/socket.c:794 [inline] sock_recvmsg net/socket.c:801 [inline] sock_recvmsg+0xd0/0x110 net/socket.c:797 sock_read_iter+0x3ba/0x5a0 net/socket.c:878 call_read_iter include/linux/fs.h:1851 [inline] do_iter_readv_writev+0x6f4/0xae0 fs/read_write.c:678 do_iter_read+0x268/0x650 fs/read_write.c:922 vfs_readv+0x175/0x1c0 fs/read_write.c:986 do_readv+0x11a/0x300 fs/read_write.c:1019 __do_sys_readv fs/read_write.c:1106 [inline] __se_sys_readv fs/read_write.c:1103 [inline] __x64_sys_readv+0x75/0xb0 fs/read_write.c:1103 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880a9164480 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 331 bytes inside of 1024-byte region [ffff8880a9164480, ffff8880a9164880) The buggy address belongs to the page: page:ffffea0002a45900 count:1 mapcount:0 mapping:ffff88812c3f0ac0 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0002a39b88 ffffea000228fe08 ffff88812c3f0ac0 raw: 0000000000000000 ffff8880a9164000 0000000100000007 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a9164480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a9164500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880a9164580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a9164600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a9164680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================