================================================================== BUG: KASAN: use-after-free in __read_once_size include/linux/compiler.h:199 [inline] BUG: KASAN: use-after-free in sock_cgroup_ptr include/linux/cgroup.h:836 [inline] BUG: KASAN: use-after-free in inet_diag_bc_sk+0xb64/0xc70 net/ipv4/inet_diag.c:749 Read of size 8 at addr ffff888091bb6240 by task syz-executor.1/11296 CPU: 0 PID: 11296 Comm: syz-executor.1 Not tainted 5.7.0-rc2-syzkaller #0 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+0x188/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd3/0x315 mm/kasan/report.c:382 __kasan_report.cold+0x35/0x4d mm/kasan/report.c:511 kasan_report+0x33/0x50 mm/kasan/common.c:625 __read_once_size include/linux/compiler.h:199 [inline] sock_cgroup_ptr include/linux/cgroup.h:836 [inline] inet_diag_bc_sk+0xb64/0xc70 net/ipv4/inet_diag.c:749 inet_diag_dump_icsk+0xbe4/0x1306 net/ipv4/inet_diag.c:1061 __inet_diag_dump+0x8d/0x240 net/ipv4/inet_diag.c:1113 netlink_dump+0x50b/0xf50 net/netlink/af_netlink.c:2245 __netlink_dump_start+0x63f/0x910 net/netlink/af_netlink.c:2353 netlink_dump_start include/linux/netlink.h:246 [inline] inet_diag_handler_cmd+0x263/0x2c0 net/ipv4/inet_diag.c:1278 __sock_diag_cmd net/core/sock_diag.c:233 [inline] sock_diag_rcv_msg+0x2fe/0x3e0 net/core/sock_diag.c:264 netlink_rcv_skb+0x15a/0x410 net/netlink/af_netlink.c:2469 sock_diag_rcv+0x26/0x40 net/core/sock_diag.c:275 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 sock_write_iter+0x289/0x3c0 net/socket.c:1004 call_write_iter include/linux/fs.h:1907 [inline] do_iter_readv_writev+0x5a8/0x850 fs/read_write.c:694 do_iter_write fs/read_write.c:999 [inline] do_iter_write+0x18b/0x600 fs/read_write.c:980 vfs_writev+0x1b3/0x2f0 fs/read_write.c:1072 do_writev+0x27f/0x300 fs/read_write.c:1115 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x45c829 Code: 0d 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 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f9ca6cfbc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 000000000050d140 RCX: 000000000045c829 RDX: 0000000000000001 RSI: 00000000200000c0 RDI: 0000000000000007 RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000d18 R14: 00000000004cb1f4 R15: 00007f9ca6cfc6d4 Allocated by task 10089: save_stack+0x1b/0x40 mm/kasan/common.c:49 set_track mm/kasan/common.c:57 [inline] __kasan_kmalloc mm/kasan/common.c:495 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:468 __kmalloc_reserve.isra.0+0x39/0xe0 net/core/skbuff.c:142 __alloc_skb+0xef/0x5a0 net/core/skbuff.c:210 alloc_skb include/linux/skbuff.h:1083 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:492 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:549 [inline] nsim_dev_trap_report_work+0x2bb/0xbc0 drivers/net/netdevsim/dev.c:590 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268 worker_thread+0x96/0xe20 kernel/workqueue.c:2414 kthread+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Freed by task 10089: save_stack+0x1b/0x40 mm/kasan/common.c:49 set_track mm/kasan/common.c:57 [inline] kasan_set_free_info mm/kasan/common.c:317 [inline] __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:456 __cache_free mm/slab.c:3426 [inline] kfree+0x109/0x2b0 mm/slab.c:3757 skb_free_head+0x8b/0xa0 net/core/skbuff.c:590 skb_release_data+0x42e/0x8b0 net/core/skbuff.c:610 skb_release_all+0x46/0x60 net/core/skbuff.c:664 __kfree_skb net/core/skbuff.c:678 [inline] consume_skb net/core/skbuff.c:837 [inline] consume_skb+0xf3/0x400 net/core/skbuff.c:831 nsim_dev_trap_report drivers/net/netdevsim/dev.c:565 [inline] nsim_dev_trap_report_work+0x86d/0xbc0 drivers/net/netdevsim/dev.c:590 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268 worker_thread+0x96/0xe20 kernel/workqueue.c:2414 kthread+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 The buggy address belongs to the object at ffff888091bb6000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 576 bytes inside of 4096-byte region [ffff888091bb6000, ffff888091bb7000) The buggy address belongs to the page: page:ffffea000246ed80 refcount:1 mapcount:0 mapping:000000006727456a index:0x0 head:ffffea000246ed80 order:1 compound_mapcount:0 flags: 0xfffe0000010200(slab|head) raw: 00fffe0000010200 ffffea0002761008 ffffea0002a40608 ffff8880aa002000 raw: 0000000000000000 ffff888091bb6000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888091bb6100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888091bb6180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888091bb6200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888091bb6280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888091bb6300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================