================================================================== BUG: KASAN: use-after-free in free_netdev+0x534/0x5b0 net/core/dev.c:10921 Read of size 8 at addr ffff888035061160 by task kworker/u4:4/1124 CPU: 1 PID: 1124 Comm: kworker/u4:4 Not tainted 5.15.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:256 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 free_netdev+0x534/0x5b0 net/core/dev.c:10921 netdev_run_todo+0x882/0xa80 net/core/dev.c:10602 default_device_exit_batch+0x2ff/0x3c0 net/core/dev.c:11581 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:593 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 16258: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] ____kasan_kmalloc mm/kasan/common.c:472 [inline] __kasan_kmalloc+0xa4/0xd0 mm/kasan/common.c:522 kmalloc_array include/linux/slab.h:631 [inline] kcalloc include/linux/slab.h:660 [inline] veth_alloc_queues drivers/net/veth.c:1314 [inline] veth_dev_init+0x114/0x2e0 drivers/net/veth.c:1341 register_netdevice+0x51e/0x1500 net/core/dev.c:10236 veth_newlink+0x58c/0xb20 drivers/net/veth.c:1726 __rtnl_newlink+0x106d/0x1750 net/core/rtnetlink.c:3458 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3506 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5572 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2485 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x86d/0xda0 net/netlink/af_netlink.c:1910 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 __sys_sendto+0x21c/0x320 net/socket.c:2036 __do_sys_sendto net/socket.c:2048 [inline] __se_sys_sendto net/socket.c:2044 [inline] __x64_sys_sendto+0xdd/0x1b0 net/socket.c:2044 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 1124: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xff/0x130 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1700 [inline] slab_free_freelist_hook+0x81/0x190 mm/slub.c:1725 slab_free mm/slub.c:3483 [inline] kfree+0xe4/0x530 mm/slub.c:4543 veth_free_queues drivers/net/veth.c:1330 [inline] veth_dev_free+0x33/0x70 drivers/net/veth.c:1352 netdev_run_todo+0x6b4/0xa80 net/core/dev.c:10600 default_device_exit_batch+0x2ff/0x3c0 net/core/dev.c:11581 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:593 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff888035061000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 352 bytes inside of 2048-byte region [ffff888035061000, ffff888035061800) The buggy address belongs to the page: page:ffffea0000d41800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x35060 head:ffffea0000d41800 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010c42000 raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 16258, ts 2220076368088, free_ts 2219311585793 prep_new_page mm/page_alloc.c:2424 [inline] get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4153 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5375 alloc_pages+0x1a7/0x300 mm/mempolicy.c:2197 alloc_slab_page mm/slub.c:1763 [inline] allocate_slab mm/slub.c:1900 [inline] new_slab+0x319/0x490 mm/slub.c:1963 ___slab_alloc+0x921/0xfe0 mm/slub.c:2994 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3081 slab_alloc_node mm/slub.c:3172 [inline] __kmalloc_node_track_caller+0x2d2/0x340 mm/slub.c:4936 kmalloc_reserve net/core/skbuff.c:352 [inline] pskb_expand_head+0x15e/0x1060 net/core/skbuff.c:1699 netlink_trim+0x1ea/0x240 net/netlink/af_netlink.c:1296 netlink_broadcast+0x5b/0xd50 net/netlink/af_netlink.c:1492 nlmsg_multicast include/net/netlink.h:1033 [inline] nlmsg_notify+0x8f/0x280 net/netlink/af_netlink.c:2528 rtnl_notify net/core/rtnetlink.c:730 [inline] rtmsg_ifinfo_send net/core/rtnetlink.c:3833 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:3848 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:3836 [inline] rtmsg_ifinfo+0xf0/0x120 net/core/rtnetlink.c:3854 __dev_notify_flags+0x226/0x2b0 net/core/dev.c:8802 rtnl_configure_link+0x16b/0x240 net/core/rtnetlink.c:3141 veth_newlink+0x4e5/0xb20 drivers/net/veth.c:1707 __rtnl_newlink+0x106d/0x1750 net/core/rtnetlink.c:3458 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1338 [inline] free_pcp_prepare+0x2c5/0x780 mm/page_alloc.c:1389 free_unref_page_prepare mm/page_alloc.c:3315 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3394 __unfreeze_partials+0x340/0x360 mm/slub.c:2495 qlink_free mm/kasan/quarantine.c:146 [inline] qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272 __kasan_slab_alloc+0x95/0xb0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slub.c:3206 [inline] slab_alloc mm/slub.c:3214 [inline] kmem_cache_alloc+0x209/0x390 mm/slub.c:3219 getname_flags.part.0+0x50/0x4f0 fs/namei.c:138 getname_flags+0x9a/0xe0 include/linux/audit.h:319 user_path_at_empty+0x2b/0x60 fs/namei.c:2800 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0x142/0x390 fs/stat.c:221 vfs_fstatat fs/stat.c:243 [inline] vfs_lstat include/linux/fs.h:3356 [inline] __do_sys_newlstat+0x91/0x110 fs/stat.c:398 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Memory state around the buggy address: ffff888035061000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888035061080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888035061100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888035061180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888035061200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================