================================================================== BUG: KASAN: slab-use-after-free in __list_add_valid_or_report+0x105/0x130 lib/list_debug.c:29 Read of size 8 at addr ffff888036c41b00 by task syz.5.2529/14679 CPU: 1 UID: 0 PID: 14679 Comm: syz.5.2529 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x156/0x4c9 mm/kasan/report.c:482 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595 __list_add_valid_or_report+0x105/0x130 lib/list_debug.c:29 __list_add_valid include/linux/list.h:96 [inline] __list_add include/linux/list.h:158 [inline] list_add include/linux/list.h:177 [inline] clone_mnt+0x633/0x930 fs/namespace.c:1275 copy_tree+0xfc/0xbf0 fs/namespace.c:2159 copy_mnt_ns+0x2bd/0xc30 fs/namespace.c:4246 create_new_namespaces+0xd3/0xac0 kernel/nsproxy.c:98 unshare_nsproxy_namespaces+0xc3/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x455/0xab0 kernel/fork.c:3174 __do_sys_unshare kernel/fork.c:3245 [inline] __se_sys_unshare kernel/fork.c:3243 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:3243 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcd83b9c629 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fcd81dd5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007fcd83e16090 RCX: 00007fcd83b9c629 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000002a020400 RBP: 00007fcd83c32b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fcd83e16128 R14: 00007fcd83e16090 R15: 00007ffe4cf093c8 Allocated by task 14266: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4501 [inline] slab_alloc_node mm/slub.c:4830 [inline] kmem_cache_alloc_noprof+0x241/0x6e0 mm/slub.c:4837 alloc_vfsmnt+0x23/0x6a0 fs/namespace.c:287 clone_mnt+0x4b/0x930 fs/namespace.c:1246 create_new_namespace fs/namespace.c:3098 [inline] open_new_namespace fs/namespace.c:3168 [inline] vfs_open_tree+0xb02/0x1500 fs/namespace.c:3217 __do_sys_open_tree fs/namespace.c:3227 [inline] __se_sys_open_tree fs/namespace.c:3225 [inline] __x64_sys_open_tree+0xa3/0x150 fs/namespace.c:3225 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 14267: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2687 [inline] slab_free mm/slub.c:6124 [inline] kmem_cache_free+0x124/0x6a0 mm/slub.c:6254 rcu_do_batch kernel/rcu/tree.c:2617 [inline] rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2869 handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xef/0x150 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 Last potentially related work creation: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556 __call_rcu_common.constprop.0+0xa5/0x9b0 kernel/rcu/tree.c:3131 task_work_run+0x150/0x240 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0x100/0x4a0 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x67c/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Second to last potentially related work creation: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556 task_work_add+0x28b/0x3b0 kernel/task_work.c:70 mntput_no_expire_slowpath+0x3da/0xb00 fs/namespace.c:1379 mntput_no_expire+0x1fd/0x220 fs/namespace.c:1406 mntput+0x6b/0xa0 fs/namespace.c:1416 create_new_namespace fs/namespace.c:3082 [inline] open_new_namespace fs/namespace.c:3168 [inline] vfs_open_tree+0x1235/0x1500 fs/namespace.c:3217 __do_sys_open_tree fs/namespace.c:3227 [inline] __se_sys_open_tree fs/namespace.c:3225 [inline] __x64_sys_open_tree+0xa3/0x150 fs/namespace.c:3225 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888036c41a40 which belongs to the cache mnt_cache of size 352 The buggy address is located 192 bytes inside of freed 352-byte region [ffff888036c41a40, ffff888036c41ba0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888036c41a40 pfn:0x36c40 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88802d25ea01 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88801d6b0000 ffffea00007db610 ffffea000070dd90 raw: ffff888036c41a40 0000000800120002 00000000f5000000 ffff88802d25ea01 head: 00fff00000000240 ffff88801d6b0000 ffffea00007db610 ffffea000070dd90 head: ffff888036c41a40 0000000800120002 00000000f5000000 ffff88802d25ea01 head: 00fff00000000001 ffffea0000db1001 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5925, tgid 5925 (syz-executor), ts 56160814571, free_ts 55996717212 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x153/0x170 mm/page_alloc.c:1888 prep_new_page mm/page_alloc.c:1896 [inline] get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3961 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5249 alloc_slab_page mm/slub.c:3255 [inline] allocate_slab mm/slub.c:3444 [inline] new_slab+0xa6/0x6d0 mm/slub.c:3502 refill_objects+0x26b/0x400 mm/slub.c:7134 refill_sheaf mm/slub.c:2804 [inline] alloc_full_sheaf mm/slub.c:2825 [inline] __pcs_replace_empty_main+0x19f/0x600 mm/slub.c:4588 alloc_from_pcs mm/slub.c:4681 [inline] slab_alloc_node mm/slub.c:4815 [inline] kmem_cache_alloc_noprof+0x480/0x6e0 mm/slub.c:4837 alloc_vfsmnt+0x23/0x6a0 fs/namespace.c:287 clone_mnt+0x4b/0x930 fs/namespace.c:1246 copy_tree+0x329/0xbf0 fs/namespace.c:2194 __do_loopback+0x2fc/0x520 fs/namespace.c:2974 do_loopback fs/namespace.c:3006 [inline] path_mount+0x1967/0x23d0 fs/namespace.c:4140 do_mount fs/namespace.c:4159 [inline] __do_sys_mount fs/namespace.c:4348 [inline] __se_sys_mount fs/namespace.c:4325 [inline] __x64_sys_mount+0x293/0x310 fs/namespace.c:4325 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5924 tgid 5924 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1432 [inline] __free_frozen_pages+0x7ca/0x10a0 mm/page_alloc.c:2977 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xe0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4501 [inline] slab_alloc_node mm/slub.c:4830 [inline] kmem_cache_alloc_node_noprof+0x25a/0x6f0 mm/slub.c:4882 __alloc_skb+0x140/0x710 net/core/skbuff.c:702 alloc_skb include/linux/skbuff.h:1383 [inline] netlink_alloc_large_skb+0x69/0x150 net/netlink/af_netlink.c:1184 netlink_sendmsg+0x680/0xda0 net/netlink/af_netlink.c:1869 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] __sys_sendto+0x4aa/0x520 net/socket.c:2206 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2209 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888036c41a00: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ffff888036c41a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888036c41b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888036c41b80: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc ffff888036c41c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================