Hello, syzbot found the following issue on: HEAD commit: 36c254515dc6 Merge tag 'powerpc-6.12-4' of git://git.kerne.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1427e440580000 kernel config: https://syzkaller.appspot.com/x/.config?x=667b897270c8ae6 dashboard link: https://syzkaller.appspot.com/bug?extid=36218cddfd84b5cc263e compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-36c25451.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/0a357f9d2448/vmlinux-36c25451.xz kernel image: https://storage.googleapis.com/syzbot-assets/fba8311d450b/bzImage-36c25451.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+36218cddfd84b5cc263e@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: slab-use-after-free in kvfree_call_rcu+0xb99/0xbe0 kernel/rcu/tree.c:3819 Write of size 8 at addr ffff888062198808 by task kworker/u32:11/1199 CPU: 1 UID: 0 PID: 1199 Comm: kworker/u32:11 Not tainted 6.12.0-rc2-syzkaller-00307-g36c254515dc6 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: netns cleanup_net Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:377 [inline] print_report+0xc3/0x620 mm/kasan/report.c:488 kasan_report+0xd9/0x110 mm/kasan/report.c:601 kvfree_call_rcu+0xb99/0xbe0 kernel/rcu/tree.c:3819 _cfg80211_unregister_wdev+0x38c/0x7f0 net/wireless/core.c:1238 ieee80211_remove_interfaces+0x36d/0x760 net/mac80211/iface.c:2300 ieee80211_unregister_hw+0x55/0x3a0 net/mac80211/main.c:1669 mac80211_hwsim_del_radio+0x268/0x370 drivers/net/wireless/virtual/mac80211_hwsim.c:5625 hwsim_exit_net+0x33f/0x6d0 drivers/net/wireless/virtual/mac80211_hwsim.c:6505 ops_exit_list+0xb0/0x180 net/core/net_namespace.c:173 cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626 process_one_work+0x958/0x1b30 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Allocated by task 5898: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:257 [inline] __do_kmalloc_node mm/slub.c:4264 [inline] __kmalloc_noprof+0x1e8/0x410 mm/slub.c:4276 kmalloc_noprof include/linux/slab.h:882 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] nl80211_set_cqm_rssi net/wireless/nl80211.c:13107 [inline] nl80211_set_cqm+0xa19/0x1780 net/wireless/nl80211.c:13174 genl_family_rcv_msg_doit+0x202/0x2f0 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x565/0x800 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2551 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline] netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1357 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1901 sock_sendmsg_nosec net/socket.c:729 [inline] __sock_sendmsg net/socket.c:744 [inline] ____sys_sendmsg+0x9ae/0xb40 net/socket.c:2607 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2661 __sys_sendmsg+0x117/0x1f0 net/socket.c:2690 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Freed by task 112: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:2342 [inline] slab_free mm/slub.c:4579 [inline] kfree+0x14f/0x4b0 mm/slub.c:4727 kvfree+0x47/0x50 mm/util.c:701 kvfree_rcu_list+0xf5/0x2c0 kernel/rcu/tree.c:3423 kvfree_rcu_drain_ready kernel/rcu/tree.c:3563 [inline] kfree_rcu_monitor+0x503/0x8b0 kernel/rcu/tree.c:3632 kfree_rcu_shrink_scan+0x245/0x3a0 kernel/rcu/tree.c:3966 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435 shrink_slab+0x32b/0x12a0 mm/shrinker.c:662 shrink_one+0x47e/0x7b0 mm/vmscan.c:4818 shrink_many mm/vmscan.c:4879 [inline] lru_gen_shrink_node mm/vmscan.c:4957 [inline] shrink_node+0x2452/0x39d0 mm/vmscan.c:5937 kswapd_shrink_node mm/vmscan.c:6765 [inline] balance_pgdat+0xc19/0x18f0 mm/vmscan.c:6957 kswapd+0x5ea/0xbf0 mm/vmscan.c:7226 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Last potentially related work creation: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xba/0xd0 mm/kasan/generic.c:541 kvfree_call_rcu+0x74/0xbe0 kernel/rcu/tree.c:3810 _cfg80211_unregister_wdev+0x38c/0x7f0 net/wireless/core.c:1238 ieee80211_remove_interfaces+0x36d/0x760 net/mac80211/iface.c:2300 ieee80211_unregister_hw+0x55/0x3a0 net/mac80211/main.c:1669 mac80211_hwsim_del_radio+0x268/0x370 drivers/net/wireless/virtual/mac80211_hwsim.c:5625 hwsim_exit_net+0x33f/0x6d0 drivers/net/wireless/virtual/mac80211_hwsim.c:6505 ops_exit_list+0xb0/0x180 net/core/net_namespace.c:173 cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626 process_one_work+0x958/0x1b30 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Second to last potentially related work creation: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xba/0xd0 mm/kasan/generic.c:541 kvfree_call_rcu+0x74/0xbe0 kernel/rcu/tree.c:3810 _cfg80211_unregister_wdev+0x38c/0x7f0 net/wireless/core.c:1238 cfg80211_netdev_notifier_call+0xa5c/0x1160 net/wireless/core.c:1494 notifier_call_chain+0xb9/0x410 kernel/notifier.c:93 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1996 call_netdevice_notifiers_extack net/core/dev.c:2034 [inline] call_netdevice_notifiers net/core/dev.c:2048 [inline] __dev_change_net_namespace+0x44f/0x12a0 net/core/dev.c:11583 dev_change_net_namespace include/linux/netdevice.h:3932 [inline] cfg80211_switch_netns+0x11e/0x690 net/wireless/core.c:169 nl80211_wiphy_netns+0x134/0x2b0 net/wireless/nl80211.c:12364 genl_family_rcv_msg_doit+0x202/0x2f0 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x565/0x800 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2551 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline] netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1357 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1901 sock_sendmsg_nosec net/socket.c:729 [inline] __sock_sendmsg net/socket.c:744 [inline] ____sys_sendmsg+0x9ae/0xb40 net/socket.c:2607 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2661 __sys_sendmsg+0x117/0x1f0 net/socket.c:2690 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e The buggy address belongs to the object at ffff888062198800 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 8 bytes inside of freed 64-byte region [ffff888062198800, ffff888062198840) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x62198 anon flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000000 ffff88801ac428c0 ffffea00017aef40 dead000000000005 raw: 0000000000000000 0000000000200020 00000001f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5424, tgid 5424 (syz-executor), ts 49927932309, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1545 [inline] get_page_from_freelist+0x101e/0x3070 mm/page_alloc.c:3457 __alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4733 alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265 alloc_slab_page mm/slub.c:2412 [inline] allocate_slab mm/slub.c:2578 [inline] new_slab+0x2ba/0x3f0 mm/slub.c:2631 ___slab_alloc+0xd1d/0x16f0 mm/slub.c:3818 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908 __slab_alloc_node mm/slub.c:3961 [inline] slab_alloc_node mm/slub.c:4122 [inline] __do_kmalloc_node mm/slub.c:4263 [inline] __kmalloc_noprof+0x379/0x410 mm/slub.c:4276 kmalloc_noprof include/linux/slab.h:882 [inline] kmalloc_array_noprof include/linux/slab.h:923 [inline] security_inode_init_security+0x140/0x390 security/security.c:1825 shmem_symlink+0x138/0x6a0 mm/shmem.c:3814 vfs_symlink fs/namei.c:4615 [inline] vfs_symlink+0x3e8/0x660 fs/namei.c:4599 do_symlinkat+0x263/0x310 fs/namei.c:4641 __do_sys_symlinkat fs/namei.c:4657 [inline] __se_sys_symlinkat fs/namei.c:4654 [inline] __ia32_sys_symlinkat+0x93/0xc0 fs/namei.c:4654 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e page_owner free stack trace missing Memory state around the buggy address: ffff888062198700: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888062198780: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff888062198800: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff888062198880: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888062198900: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup