================================================================== BUG: KASAN: use-after-free in do_shrink_slab+0xb15/0xbd0 mm/vmscan.c:774 Read of size 8 at addr ffff888049c1b5b8 by task syz-fuzzer/3771 CPU: 2 PID: 3771 Comm: syz-fuzzer Not tainted 6.0.0-syzkaller-07362-g62e6e5940c0c #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 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 do_shrink_slab+0xb15/0xbd0 mm/vmscan.c:774 shrink_slab+0x17c/0x6f0 mm/vmscan.c:991 shrink_node_memcgs mm/vmscan.c:3182 [inline] shrink_node+0x8c9/0x1e80 mm/vmscan.c:3304 shrink_zones mm/vmscan.c:3542 [inline] do_try_to_free_pages+0x3b4/0x17a0 mm/vmscan.c:3601 try_to_free_pages+0x2a7/0x840 mm/vmscan.c:3836 __perform_reclaim mm/page_alloc.c:4750 [inline] __alloc_pages_direct_reclaim mm/page_alloc.c:4772 [inline] __alloc_pages_slowpath.constprop.0+0x88a/0x2300 mm/page_alloc.c:5177 __alloc_pages+0x43d/0x510 mm/page_alloc.c:5562 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2270 folio_alloc+0x1c/0x70 mm/mempolicy.c:2280 filemap_alloc_folio+0x306/0x3a0 mm/filemap.c:970 page_cache_ra_unbounded+0x1aa/0x5e0 mm/readahead.c:248 do_page_cache_ra mm/readahead.c:300 [inline] page_cache_ra_order+0x6e8/0xa00 mm/readahead.c:560 do_sync_mmap_readahead mm/filemap.c:3035 [inline] filemap_fault+0x1669/0x2640 mm/filemap.c:3127 __do_fault+0x10d/0x610 mm/memory.c:4173 do_read_fault mm/memory.c:4524 [inline] do_fault mm/memory.c:4653 [inline] handle_pte_fault mm/memory.c:4917 [inline] __handle_mm_fault+0x2130/0x39b0 mm/memory.c:5059 handle_mm_fault+0x1c8/0x780 mm/memory.c:5157 do_user_addr_fault+0x475/0x1210 arch/x86/mm/fault.c:1407 handle_page_fault arch/x86/mm/fault.c:1498 [inline] exc_page_fault+0x94/0x170 arch/x86/mm/fault.c:1554 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570 RIP: 0033:0x452c5c Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc 48 83 ec 18 48 89 6c 24 10 48 8d 6c 24 10 48 89 44 24 20 48 85 db 0f 86 5c 01 00 00 <0f> b6 10 90 85 d2 75 18 45 84 c0 75 13 31 c0 31 db 48 89 d9 31 ff RSP: 002b:000000c001d07778 EFLAGS: 00010206 RAX: 0000000000e30f41 RBX: 00000000000d0847 RCX: 00000000000d0847 RDX: 00000000000d0847 RSI: 000000c001d077cc RDI: 000000c001d077d8 RBP: 000000c001d07788 R08: 0000000000000001 R09: 0000000000e30f41 R10: 000000000052e660 R11: 0000000000053321 R12: 000000000052e660 R13: 00000000000d0847 R14: 000000c01ca7e820 R15: ffffffffffffffff Allocated by task 4301: 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 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x445/0x920 kernel/fork.c:3181 __do_sys_unshare kernel/fork.c:3252 [inline] __se_sys_unshare kernel/fork.c:3250 [inline] __ia32_sys_unshare+0x2c/0x40 kernel/fork.c:3250 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 4301: 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 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x445/0x920 kernel/fork.c:3181 __do_sys_unshare kernel/fork.c:3252 [inline] __se_sys_unshare kernel/fork.c:3250 [inline] __ia32_sys_unshare+0x2c/0x40 kernel/fork.c:3250 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 ffff888049c1b000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1464 bytes inside of 2048-byte region [ffff888049c1b000, ffff888049c1b800) The buggy address belongs to the physical page: page:ffffea0001270600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x49c18 head:ffffea0001270600 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4fff00000010200(slab|head|node=1|zone=1|lastcpupid=0x7ff) raw: 04fff00000010200 ffffea00013a3c00 dead000000000002 ffff888011842f00 raw: 0000000000000000 0000000080080008 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4294, tgid 4282 (syz-executor.3), ts 248792317076, free_ts 246942849430 prep_new_page mm/page_alloc.c:2532 [inline] get_page_from_freelist+0x109b/0x2ce0 mm/page_alloc.c:4283 __alloc_pages_slowpath.constprop.0+0x34d/0x2300 mm/page_alloc.c:5084 __alloc_pages+0x43d/0x510 mm/page_alloc.c:5562 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] slab_alloc mm/slub.c:3256 [inline] kmem_cache_alloc_trace+0x323/0x3e0 mm/slub.c:3287 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:733 [inline] copy_verifier_state+0x827/0xb80 kernel/bpf/verifier.c:1211 is_state_visited kernel/bpf/verifier.c:12060 [inline] do_check kernel/bpf/verifier.c:12175 [inline] do_check_common+0x1a22/0xcc20 kernel/bpf/verifier.c:14642 do_check_main kernel/bpf/verifier.c:14705 [inline] bpf_check+0x734c/0xac10 kernel/bpf/verifier.c:15275 bpf_prog_load+0x13cb/0x2230 kernel/bpf/syscall.c:2605 __sys_bpf+0x1605/0x4cf0 kernel/bpf/syscall.c:4965 __do_sys_bpf kernel/bpf/syscall.c:5069 [inline] __se_sys_bpf kernel/bpf/syscall.c:5067 [inline] __ia32_sys_bpf+0x74/0xc0 kernel/bpf/syscall.c:5067 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 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 __folio_put_large mm/swap.c:118 [inline] __folio_put+0x105/0x130 mm/swap.c:126 folio_put include/linux/mm.h:1125 [inline] put_page include/linux/mm.h:1177 [inline] __skb_frag_unref include/linux/skbuff.h:3383 [inline] skb_release_data+0x51e/0x870 net/core/skbuff.c:783 skb_release_all net/core/skbuff.c:854 [inline] __kfree_skb+0x46/0x60 net/core/skbuff.c:868 __tcp_close+0x230/0xf50 net/ipv4/tcp.c:2887 tcp_close+0x29/0xc0 net/ipv4/tcp.c:3031 inet_release+0x12e/0x270 net/ipv4/af_inet.c:428 inet6_release+0x4c/0x70 net/ipv6/af_inet6.c:482 __sock_release+0xcd/0x280 net/socket.c:650 sock_close+0x18/0x20 net/socket.c:1365 __fput+0x27c/0xa90 fs/file_table.c:320 task_work_run+0xdd/0x1a0 kernel/task_work.c:177 get_signal+0x1c3/0x2610 kernel/signal.c:2634 arch_do_signal_or_restart+0x82/0x2300 arch/x86/kernel/signal.c:869 exit_to_user_mode_loop kernel/entry/common.c:166 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:201 Memory state around the buggy address: ffff888049c1b480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888049c1b500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888049c1b580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888049c1b600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888049c1b680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================