================================================================== BUG: KASAN: slab-use-after-free in pwq_release_workfn+0x339/0x380 kernel/workqueue.c:4124 Read of size 4 at addr ffff8880779ac1c0 by task pool_workqueue_/3 CPU: 1 PID: 3 Comm: pool_workqueue_ Not tainted 6.6.0-rc2-syzkaller-00245-ga59addacf899 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report+0xda/0x110 mm/kasan/report.c:588 pwq_release_workfn+0x339/0x380 kernel/workqueue.c:4124 kthread_worker_fn+0x2ff/0xac0 kernel/kthread.c:823 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Allocated by task 8742: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0xa2/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:599 [inline] kzalloc include/linux/slab.h:720 [inline] alloc_workqueue+0x16f/0x1490 kernel/workqueue.c:4684 wg_newlink+0x353/0x8f0 drivers/net/wireguard/device.c:343 rtnl_newlink_create net/core/rtnetlink.c:3485 [inline] __rtnl_newlink+0x1177/0x1940 net/core/rtnetlink.c:3705 rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3718 rtnetlink_rcv_msg+0x3c4/0xdf0 net/core/rtnetlink.c:6444 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline] netlink_unicast+0x536/0x810 net/netlink/af_netlink.c:1368 netlink_sendmsg+0x93c/0xe40 net/netlink/af_netlink.c:1910 sock_sendmsg_nosec net/socket.c:730 [inline] sock_sendmsg+0xd9/0x180 net/socket.c:753 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2541 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2595 __sys_sendmsg+0x117/0x1e0 net/socket.c:2624 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 8742: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:522 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x15b/0x1b0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826 slab_free mm/slub.c:3809 [inline] __kmem_cache_free+0xb8/0x2f0 mm/slub.c:3822 alloc_workqueue+0xe76/0x1490 kernel/workqueue.c:4746 wg_newlink+0x353/0x8f0 drivers/net/wireguard/device.c:343 rtnl_newlink_create net/core/rtnetlink.c:3485 [inline] __rtnl_newlink+0x1177/0x1940 net/core/rtnetlink.c:3705 rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3718 rtnetlink_rcv_msg+0x3c4/0xdf0 net/core/rtnetlink.c:6444 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline] netlink_unicast+0x536/0x810 net/netlink/af_netlink.c:1368 netlink_sendmsg+0x93c/0xe40 net/netlink/af_netlink.c:1910 sock_sendmsg_nosec net/socket.c:730 [inline] sock_sendmsg+0xd9/0x180 net/socket.c:753 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2541 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2595 __sys_sendmsg+0x117/0x1e0 net/socket.c:2624 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 __call_rcu_common.constprop.0+0x9a/0x790 kernel/rcu/tree.c:2653 pwq_release_workfn+0x244/0x380 kernel/workqueue.c:4138 kthread_worker_fn+0x2ff/0xac0 kernel/kthread.c:823 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Second to last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 insert_work+0x38/0x230 kernel/workqueue.c:1647 __queue_work+0xb77/0x1050 kernel/workqueue.c:1803 call_timer_fn+0x19e/0x580 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1746 [inline] __run_timers+0x585/0xb10 kernel/time/timer.c:2022 run_timer_softirq+0x58/0xd0 kernel/time/timer.c:2035 __do_softirq+0x218/0x965 kernel/softirq.c:553 The buggy address belongs to the object at ffff8880779ac000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 448 bytes inside of freed 512-byte region [ffff8880779ac000, ffff8880779ac200) The buggy address belongs to the physical page: page:ffffea0001de6b00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x779ac head:ffffea0001de6b00 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888012c41c80 ffffea00009cb000 dead000000000002 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 29239, tgid 29238 (syz-executor.4), ts 833772426371, free_ts 833579226268 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1536 prep_new_page mm/page_alloc.c:1543 [inline] get_page_from_freelist+0xee0/0x2f20 mm/page_alloc.c:3170 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4426 alloc_pages+0x1a9/0x270 mm/mempolicy.c:2298 alloc_slab_page mm/slub.c:1870 [inline] allocate_slab+0x251/0x380 mm/slub.c:2017 new_slab mm/slub.c:2070 [inline] ___slab_alloc+0x8c7/0x1580 mm/slub.c:3223 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322 __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x131/0x340 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1022 [inline] __kmalloc+0x4f/0x100 mm/slab_common.c:1036 kmalloc include/linux/slab.h:603 [inline] kzalloc include/linux/slab.h:720 [inline] copy_splice_read+0x1ac/0x8f0 fs/splice.c:338 vfs_splice_read fs/splice.c:992 [inline] vfs_splice_read+0x2ea/0x3b0 fs/splice.c:962 splice_direct_to_actor+0x2a5/0xa30 fs/splice.c:1069 do_splice_direct+0x1af/0x280 fs/splice.c:1194 do_sendfile+0xb88/0x1390 fs/read_write.c:1254 __do_sys_sendfile64 fs/read_write.c:1322 [inline] __se_sys_sendfile64 fs/read_write.c:1308 [inline] __x64_sys_sendfile64+0x1d6/0x220 fs/read_write.c:1308 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1136 [inline] free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2312 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2405 bpf_check+0x11d4/0xabd0 kernel/bpf/verifier.c:19896 bpf_prog_load+0x153a/0x2270 kernel/bpf/syscall.c:2708 __sys_bpf+0xeed/0x4d30 kernel/bpf/syscall.c:5335 __do_sys_bpf kernel/bpf/syscall.c:5439 [inline] __se_sys_bpf kernel/bpf/syscall.c:5437 [inline] __x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:5437 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff8880779ac080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880779ac100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880779ac180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880779ac200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880779ac280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================