================================================================== BUG: KASAN: slab-use-after-free in pwq_release_workfn+0x253/0x260 kernel/workqueue.c:4124 Read of size 4 at addr ffff88806731e5c0 by task pool_workqueue_/3 CPU: 0 PID: 3 Comm: pool_workqueue_ Not tainted 6.6.0-rc1-syzkaller #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+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0x163/0x540 mm/kasan/report.c:475 kasan_report+0x175/0x1b0 mm/kasan/report.c:588 pwq_release_workfn+0x253/0x260 kernel/workqueue.c:4124 kthread_worker_fn+0x49a/0x9f0 kernel/kthread.c:823 kthread+0x2b8/0x350 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Allocated by task 5155: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:599 [inline] kzalloc include/linux/slab.h:720 [inline] alloc_workqueue+0x172/0x1520 kernel/workqueue.c:4684 loop_configure+0x613/0x1250 drivers/block/loop.c:1058 lo_ioctl+0x8f5/0x2080 blkdev_ioctl+0x5cf/0x730 block/ioctl.c:630 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xf8/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 5155: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook mm/slub.c:1826 [inline] slab_free mm/slub.c:3809 [inline] __kmem_cache_free+0x25f/0x3b0 mm/slub.c:3822 alloc_workqueue+0xeba/0x1520 kernel/workqueue.c:4746 loop_configure+0x613/0x1250 drivers/block/loop.c:1058 lo_ioctl+0x8f5/0x2080 blkdev_ioctl+0x5cf/0x730 block/ioctl.c:630 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xf8/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff88806731e400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 448 bytes inside of freed 512-byte region [ffff88806731e400, ffff88806731e600) The buggy address belongs to the physical page: page:ffffea00019cc700 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6731c head:ffffea00019cc700 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 ffff888012841c80 dead000000000122 0000000000000000 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 9, tgid 9 (kworker/0:1), ts 64718813944, free_ts 64613099674 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1536 prep_new_page mm/page_alloc.c:1543 [inline] get_page_from_freelist+0x31db/0x3360 mm/page_alloc.c:3170 __alloc_pages+0x255/0x670 mm/page_alloc.c:4426 alloc_slab_page+0x6a/0x160 mm/slub.c:1870 allocate_slab mm/slub.c:2017 [inline] new_slab+0x84/0x2f0 mm/slub.c:2070 ___slab_alloc+0xade/0x1100 mm/slub.c:3223 __slab_alloc mm/slub.c:3322 [inline] __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x1af/0x270 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1022 [inline] __kmalloc+0xa8/0x230 mm/slab_common.c:1036 kmalloc include/linux/slab.h:603 [inline] kzalloc include/linux/slab.h:720 [inline] ieee80211_ibss_build_presp+0x118/0x18c0 net/mac80211/ibss.c:70 __ieee80211_sta_join_ibss+0x708/0x1610 net/mac80211/ibss.c:316 ieee80211_sta_create_ibss+0x36e/0x610 net/mac80211/ibss.c:1352 ieee80211_sta_find_ibss net/mac80211/ibss.c:1482 [inline] ieee80211_ibss_work+0xdd7/0x1490 net/mac80211/ibss.c:1709 cfg80211_wiphy_work+0x21e/0x250 net/wireless/core.c:435 process_one_work+0x781/0x1130 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0xabf/0x1060 kernel/workqueue.c:2784 kthread+0x2b8/0x350 kernel/kthread.c:388 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+0x8c3/0x9f0 mm/page_alloc.c:2312 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2405 free_large_kmalloc+0xff/0x190 mm/slab_common.c:1000 skb_kfree_head net/core/skbuff.c:945 [inline] skb_free_head net/core/skbuff.c:957 [inline] skb_release_data+0x660/0x850 net/core/skbuff.c:987 skb_release_all net/core/skbuff.c:1053 [inline] __kfree_skb net/core/skbuff.c:1067 [inline] consume_skb+0xb3/0x150 net/core/skbuff.c:1283 netlink_recvmsg+0x60a/0x11d0 net/netlink/af_netlink.c:1988 sock_recvmsg_nosec net/socket.c:1027 [inline] sock_recvmsg net/socket.c:1049 [inline] ____sys_recvmsg+0x2a4/0x580 net/socket.c:2760 ___sys_recvmsg net/socket.c:2802 [inline] __sys_recvmsg+0x2f0/0x3d0 net/socket.c:2832 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff88806731e480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806731e500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88806731e580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806731e600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88806731e680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================