================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0x2de0/0x3cb0 kernel/locking/lockdep.c:5007 Read of size 8 at addr ffff888012298018 by task kswapd0/112 CPU: 0 UID: 0 PID: 112 Comm: kswapd0 Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 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 __lock_acquire+0x2de0/0x3cb0 kernel/locking/lockdep.c:5007 lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 p9_tag_remove net/9p/client.c:397 [inline] p9_req_put net/9p/client.c:405 [inline] p9_req_put+0xaf/0x250 net/9p/client.c:402 req_done+0x1e7/0x2f0 net/9p/trans_virtio.c:147 vring_interrupt drivers/virtio/virtio_ring.c:2595 [inline] vring_interrupt+0x31b/0x400 drivers/virtio/virtio_ring.c:2570 __handle_irq_event_percpu+0x229/0x7c0 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x263/0xd10 kernel/irq/chip.c:831 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline] handle_irq arch/x86/kernel/irq.c:247 [inline] call_irq_handler arch/x86/kernel/irq.c:259 [inline] __common_interrupt+0xdf/0x250 arch/x86/kernel/irq.c:285 common_interrupt+0xab/0xd0 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x0/0x20 kernel/kcov.c:312 Code: 0c 24 0f b7 d6 0f b7 f7 bf 03 00 00 00 e9 58 fe ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 0c 24 89 f2 89 fe bf 05 00 00 00 e9 2a fe ff ff RSP: 0018:ffffc90001fd76c8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000041 RCX: ffffffff81da33ab RDX: 1ffff1100358c718 RSI: 0000000000000041 RDI: 0000000000000100 RBP: ffff88801ac638d8 R08: 0000000000000005 R09: 0000000000000100 R10: 0000000000000040 R11: 0000000000000000 R12: 0000000000000000 R13: ffff88801ac632b0 R14: dffffc0000000000 R15: 0000000000000002 vmap_node_shrink_count+0xbb/0x160 mm/vmalloc.c:5073 do_shrink_slab+0x82/0x11c0 mm/shrinker.c:382 shrink_slab+0x330/0x12c0 mm/shrinker.c:662 shrink_one+0x47e/0x7b0 mm/vmscan.c:4795 shrink_many mm/vmscan.c:4856 [inline] lru_gen_shrink_node mm/vmscan.c:4934 [inline] shrink_node+0x2452/0x39d0 mm/vmscan.c:5914 kswapd_shrink_node mm/vmscan.c:6742 [inline] balance_pgdat+0xc19/0x18f0 mm/vmscan.c:6934 kswapd+0x5ea/0xbf0 mm/vmscan.c:7203 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 Allocated by task 6018: 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:370 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:387 kmalloc_noprof include/linux/slab.h:681 [inline] p9_client_create+0xcf/0x11b0 net/9p/client.c:983 v9fs_session_init+0x1f8/0x1a80 fs/9p/v9fs.c:410 v9fs_mount+0xc6/0xa50 fs/9p/vfs_super.c:122 legacy_get_tree+0x109/0x220 fs/fs_context.c:662 vfs_get_tree+0x8f/0x380 fs/super.c:1800 do_new_mount fs/namespace.c:3472 [inline] path_mount+0x6e1/0x1f10 fs/namespace.c:3799 do_mount fs/namespace.c:3812 [inline] __do_sys_mount fs/namespace.c:4020 [inline] __se_sys_mount fs/namespace.c:3997 [inline] __ia32_sys_mount+0x292/0x310 fs/namespace.c:3997 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 6018: 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+0xf7/0x160 mm/kasan/common.c:240 __kasan_slab_free+0x32/0x50 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2256 [inline] slab_free mm/slub.c:4477 [inline] kfree+0x12a/0x3b0 mm/slub.c:4598 p9_client_create+0x9ca/0x11b0 net/9p/client.c:1054 v9fs_session_init+0x1f8/0x1a80 fs/9p/v9fs.c:410 v9fs_mount+0xc6/0xa50 fs/9p/vfs_super.c:122 legacy_get_tree+0x109/0x220 fs/fs_context.c:662 vfs_get_tree+0x8f/0x380 fs/super.c:1800 do_new_mount fs/namespace.c:3472 [inline] path_mount+0x6e1/0x1f10 fs/namespace.c:3799 do_mount fs/namespace.c:3812 [inline] __do_sys_mount fs/namespace.c:4020 [inline] __se_sys_mount fs/namespace.c:3997 [inline] __ia32_sys_mount+0x292/0x310 fs/namespace.c:3997 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 ffff888012298000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 24 bytes inside of freed 512-byte region [ffff888012298000, ffff888012298200) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12298 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xfdffffff(slab) raw: 00fff00000000040 ffff88801ac42c80 ffffea0000900200 dead000000000002 raw: 0000000000000000 0000000080100010 00000001fdffffff 0000000000000000 head: 00fff00000000040 ffff88801ac42c80 ffffea0000900200 dead000000000002 head: 0000000000000000 0000000080100010 00000001fdffffff 0000000000000000 head: 00fff00000000002 ffffea000048a601 ffffffffffffffff 0000000000000000 head: 0000000000000004 0000000000000000 00000000ffffffff 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 5647, tgid 5647 (syz-executor), ts 63974893131, free_ts 63938211796 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1500 prep_new_page mm/page_alloc.c:1508 [inline] get_page_from_freelist+0x1351/0x2e50 mm/page_alloc.c:3446 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4702 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_pages_node_noprof include/linux/gfp.h:296 [inline] alloc_slab_page+0x4e/0xf0 mm/slub.c:2325 allocate_slab mm/slub.c:2488 [inline] new_slab+0x84/0x260 mm/slub.c:2541 ___slab_alloc+0xdac/0x1870 mm/slub.c:3727 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3817 __slab_alloc_node mm/slub.c:3870 [inline] slab_alloc_node mm/slub.c:4029 [inline] __do_kmalloc_node mm/slub.c:4161 [inline] __kmalloc_noprof+0x379/0x410 mm/slub.c:4174 kmalloc_noprof include/linux/slab.h:685 [inline] kzalloc_noprof include/linux/slab.h:807 [inline] fib6_info_alloc+0x40/0x160 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x337/0x1aa0 net/ipv6/route.c:3761 ip6_route_add+0x26/0x1c0 net/ipv6/route.c:3853 addrconf_prefix_route+0x2fe/0x510 net/ipv6/addrconf.c:2486 inet6_addr_add+0x698/0xbc0 net/ipv6/addrconf.c:3063 inet6_rtm_newaddr+0x11d4/0x1aa0 net/ipv6/addrconf.c:5048 rtnetlink_rcv_msg+0x3c7/0xea0 net/core/rtnetlink.c:6647 netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2550 page last free pid 5693 tgid 5693 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1101 [inline] free_unref_page+0x64a/0xe40 mm/page_alloc.c:2619 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3992 [inline] slab_alloc_node mm/slub.c:4041 [inline] kmem_cache_alloc_noprof+0x121/0x2f0 mm/slub.c:4048 anon_vma_chain_alloc mm/rmap.c:142 [inline] __anon_vma_prepare+0xae/0x5e0 mm/rmap.c:195 vmf_anon_prepare+0x11c/0x250 mm/memory.c:3289 do_cow_fault mm/memory.c:5081 [inline] do_fault mm/memory.c:5193 [inline] do_pte_missing mm/memory.c:3947 [inline] handle_pte_fault mm/memory.c:5521 [inline] __handle_mm_fault+0x1001/0x5400 mm/memory.c:5664 handle_mm_fault+0x498/0xa60 mm/memory.c:5832 do_user_addr_fault+0x7a3/0x13f0 arch/x86/mm/fault.c:1389 handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 Memory state around the buggy address: ffff888012297f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888012297f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888012298000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888012298080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888012298100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 0c 24 or $0x24,%al 2: 0f b7 d6 movzwl %si,%edx 5: 0f b7 f7 movzwl %di,%esi 8: bf 03 00 00 00 mov $0x3,%edi d: e9 58 fe ff ff jmp 0xfffffe6a 12: 0f 1f 84 00 00 00 00 nopl 0x0(%rax,%rax,1) 19: 00 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 90 nop 1e: 90 nop 1f: 90 nop 20: 90 nop 21: 90 nop 22: 90 nop 23: 90 nop 24: 90 nop 25: 90 nop 26: 90 nop 27: 90 nop 28: 90 nop 29: 90 nop * 2a: f3 0f 1e fa endbr64 <-- trapping instruction 2e: 48 8b 0c 24 mov (%rsp),%rcx 32: 89 f2 mov %esi,%edx 34: 89 fe mov %edi,%esi 36: bf 05 00 00 00 mov $0x5,%edi 3b: e9 2a fe ff ff jmp 0xfffffe6a