================================================================== BUG: KASAN: use-after-free in do_shrink_slab+0xb15/0xbd0 mm/vmscan.c:774 Read of size 8 at addr ffff888012abf5b8 by task kswapd1/130 CPU: 3 PID: 130 Comm: kswapd1 Not tainted 6.0.0-syzkaller-07994-ge8bc52cb8df8 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:317 [inline] print_report.cold+0x2ba/0x719 mm/kasan/report.c:433 kasan_report+0xb1/0x1e0 mm/kasan/report.c:495 do_shrink_slab+0xb15/0xbd0 mm/vmscan.c:774 shrink_slab+0x17c/0x6f0 mm/vmscan.c:991 shrink_node_memcgs mm/vmscan.c:3182 [inline] shrink_node+0x8c9/0x1e80 mm/vmscan.c:3304 kswapd_shrink_node mm/vmscan.c:4086 [inline] balance_pgdat+0x8ef/0x1580 mm/vmscan.c:4277 kswapd+0x79b/0xf80 mm/vmscan.c:4537 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Allocated by task 14018: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:437 [inline] ____kasan_kmalloc mm/kasan/common.c:516 [inline] ____kasan_kmalloc mm/kasan/common.c:475 [inline] __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:525 kmalloc include/linux/slab.h:605 [inline] kzalloc include/linux/slab.h:733 [inline] ops_init+0xfb/0x470 net/core/net_namespace.c:124 setup_net+0x5d1/0xc50 net/core/net_namespace.c:325 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x304d/0x7090 kernel/fork.c:2257 kernel_clone+0xe7/0xab0 kernel/fork.c:2671 __do_compat_sys_ia32_clone+0x9e/0xd0 arch/x86/kernel/sys_ia32.c:254 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 Freed by task 14018: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:367 [inline] ____kasan_slab_free+0x166/0x1c0 mm/kasan/common.c:329 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1759 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1785 slab_free mm/slub.c:3539 [inline] kfree+0xe2/0x580 mm/slub.c:4567 ops_init+0xcd/0x470 net/core/net_namespace.c:139 setup_net+0x5d1/0xc50 net/core/net_namespace.c:325 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x304d/0x7090 kernel/fork.c:2257 kernel_clone+0xe7/0xab0 kernel/fork.c:2671 __do_compat_sys_ia32_clone+0x9e/0xd0 arch/x86/kernel/sys_ia32.c:254 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 Last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348 call_rcu+0x99/0x790 kernel/rcu/tree.c:2796 netlink_release+0xeff/0x1db0 net/netlink/af_netlink.c:815 __sock_release net/socket.c:650 [inline] sock_release+0x87/0x1b0 net/socket.c:678 netlink_kernel_release+0x4b/0x60 net/netlink/af_netlink.c:2107 diag_net_exit+0x34/0x70 net/core/sock_diag.c:325 ops_exit_list+0xb0/0x170 net/core/net_namespace.c:162 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:594 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Second to last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348 call_rcu+0x99/0x790 kernel/rcu/tree.c:2796 netlink_release+0xeff/0x1db0 net/netlink/af_netlink.c:815 __sock_release+0xcd/0x280 net/socket.c:650 sock_close+0x18/0x20 net/socket.c:1365 __fput+0x27c/0xa90 fs/file_table.c:320 task_work_run+0xdd/0x1a0 kernel/task_work.c:177 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:169 [inline] exit_to_user_mode_prepare+0x23c/0x250 kernel/entry/common.c:201 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline] syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:294 __do_fast_syscall_32+0x72/0xf0 arch/x86/entry/common.c:181 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 The buggy address belongs to the object at ffff888012abf000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1464 bytes inside of 2048-byte region [ffff888012abf000, ffff888012abf800) The buggy address belongs to the physical page: page:ffffea00004aae00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12ab8 head:ffffea00004aae00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0000958e00 dead000000000002 ffff888011842f00 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3702, tgid 3702 (syz-executor.0), ts 184338065772, free_ts 50442351974 prep_new_page mm/page_alloc.c:2532 [inline] get_page_from_freelist+0x109b/0x2ce0 mm/page_alloc.c:4283 __alloc_pages+0x1c7/0x510 mm/page_alloc.c:5549 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:1829 [inline] allocate_slab+0x27e/0x3d0 mm/slub.c:1974 new_slab mm/slub.c:2034 [inline] ___slab_alloc+0x84f/0xe80 mm/slub.c:3036 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3123 slab_alloc_node mm/slub.c:3214 [inline] slab_alloc mm/slub.c:3256 [inline] kmem_cache_alloc_trace+0x323/0x3e0 mm/slub.c:3287 kmalloc include/linux/slab.h:600 [inline] rtnl_newlink+0x46/0xa0 net/core/rtnetlink.c:3590 rtnetlink_rcv_msg+0x43a/0xca0 net/core/rtnetlink.c:6091 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2540 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x917/0xe10 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:734 __sys_sendto+0x236/0x340 net/socket.c:2117 __do_compat_sys_socketcall+0x47f/0x660 net/compat.c:473 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1449 [inline] free_pcp_prepare+0x5e4/0xd20 mm/page_alloc.c:1499 free_unref_page_prepare mm/page_alloc.c:3380 [inline] free_unref_page+0x19/0x4d0 mm/page_alloc.c:3476 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:447 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:727 [inline] slab_alloc_node mm/slub.c:3248 [inline] kmem_cache_alloc_node+0x2b1/0x3f0 mm/slub.c:3298 __alloc_skb+0x210/0x2f0 net/core/skbuff.c:497 alloc_skb_fclone include/linux/skbuff.h:1315 [inline] tcp_stream_alloc_skb+0x38/0x580 net/ipv4/tcp.c:861 tcp_sendmsg_locked+0xc4b/0x2940 net/ipv4/tcp.c:1324 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1482 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:819 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:734 sock_write_iter+0x291/0x3d0 net/socket.c:1108 call_write_iter include/linux/fs.h:2190 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x9e9/0xdd0 fs/read_write.c:584 ksys_write+0x1e8/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 Memory state around the buggy address: ffff888012abf480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888012abf500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888012abf580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888012abf600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888012abf680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================