================================================================== BUG: KASAN: use-after-free in __list_add_valid+0xa5/0xb0 lib/list_debug.c:30 Read of size 8 at addr ffff8880438795c8 by task syz-executor.0/4285 CPU: 0 PID: 4285 Comm: syz-executor.0 Not tainted 6.0.0-syzkaller-09589-g55be6084c8e0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 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 __list_add_valid+0xa5/0xb0 lib/list_debug.c:30 __list_add include/linux/list.h:69 [inline] list_add_tail include/linux/list.h:102 [inline] register_shrinker_prepared+0x37/0x120 mm/vmscan.c:684 sget_fc+0x5e7/0x7c0 fs/super.c:581 vfs_get_super fs/super.c:1163 [inline] get_tree_nodev+0x24/0x1d0 fs/super.c:1198 mqueue_get_tree+0xee/0x130 ipc/mqueue.c:435 vfs_get_tree+0x89/0x2f0 fs/super.c:1530 fc_mount+0x13/0xc0 fs/namespace.c:1043 mq_create_mount ipc/mqueue.c:485 [inline] mq_init_ns+0x43e/0x630 ipc/mqueue.c:1701 create_ipc_ns ipc/namespace.c:58 [inline] copy_ipcs+0x35e/0x5e0 ipc/namespace.c:94 create_new_namespaces+0x210/0xb20 kernel/nsproxy.c:90 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x445/0x920 kernel/fork.c:3182 __do_sys_unshare kernel/fork.c:3253 [inline] __se_sys_unshare kernel/fork.c:3251 [inline] __ia32_sys_unshare+0x2c/0x40 kernel/fork.c:3251 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 RIP: 0023:0xf7fef549 Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f7fc95cc EFLAGS: 00000296 ORIG_RAX: 0000000000000136 RAX: ffffffffffffffda RBX: 000000006c060000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 4266: 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+0x307b/0x7110 kernel/fork.c:2257 kernel_clone+0xe7/0x8f0 kernel/fork.c:2672 __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 4266: 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+0x307b/0x7110 kernel/fork.c:2257 kernel_clone+0xe7/0x8f0 kernel/fork.c:2672 __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 The buggy address belongs to the object at ffff888043879000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1480 bytes inside of 2048-byte region [ffff888043879000, ffff888043879800) The buggy address belongs to the physical page: page:ffffea00010e1e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88804387d000 pfn:0x43878 head:ffffea00010e1e00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001ef0008 ffffea00010cb808 ffff888011842000 raw: ffff88804387d000 0000000000080004 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 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3660, tgid 3660 (syz-executor.2), ts 118785242529, free_ts 11122389500 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] __kmalloc_node_track_caller+0x2f1/0x390 mm/slub.c:4964 kmalloc_reserve net/core/skbuff.c:437 [inline] pskb_expand_head+0x203/0x1110 net/core/skbuff.c:1832 netlink_trim+0x1ea/0x240 net/netlink/af_netlink.c:1301 netlink_broadcast+0x5f/0xd90 net/netlink/af_netlink.c:1497 nlmsg_multicast include/net/netlink.h:1044 [inline] nlmsg_notify+0x8f/0x280 net/netlink/af_netlink.c:2583 rtnl_notify net/core/rtnetlink.c:767 [inline] rtmsg_ifinfo_send net/core/rtnetlink.c:3929 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:3944 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:3932 [inline] rtmsg_ifinfo+0xf0/0x120 net/core/rtnetlink.c:3950 __dev_notify_flags+0x226/0x2b0 net/core/dev.c:8573 dev_change_flags+0x112/0x170 net/core/dev.c:8615 do_setlink+0x9f1/0x3bb0 net/core/rtnetlink.c:2788 __rtnl_newlink+0xd6a/0x17e0 net/core/rtnetlink.c:3547 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 free_contig_range+0xb1/0x180 mm/page_alloc.c:9457 destroy_args+0xa8/0x646 mm/debug_vm_pgtable.c:1031 debug_vm_pgtable+0x2945/0x29d6 mm/debug_vm_pgtable.c:1354 do_one_initcall+0xfe/0x650 init/main.c:1296 do_initcall_level init/main.c:1369 [inline] do_initcalls init/main.c:1385 [inline] do_basic_setup init/main.c:1404 [inline] kernel_init_freeable+0x6b1/0x73a init/main.c:1623 kernel_init+0x1a/0x1d0 init/main.c:1512 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Memory state around the buggy address: ffff888043879480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888043879500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888043879580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888043879600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888043879680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 03 74 c0 01 add 0x1(%rax,%rax,8),%esi 4: 10 05 03 74 b8 01 adc %al,0x1b87403(%rip) # 0x1b8740d a: 10 06 adc %al,(%rsi) c: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 10: 10 07 adc %al,(%rdi) 12: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi 16: 10 08 adc %cl,(%rax) 18: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1c: 00 00 add %al,(%rax) 1e: 00 00 add %al,(%rax) 20: 00 51 52 add %dl,0x52(%rcx) 23: 55 push %rbp 24: 89 e5 mov %esp,%ebp 26: 0f 34 sysenter 28: cd 80 int $0x80 * 2a: 5d pop %rbp <-- trapping instruction 2b: 5a pop %rdx 2c: 59 pop %rcx 2d: c3 retq 2e: 90 nop 2f: 90 nop 30: 90 nop 31: 90 nop 32: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 39: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi