================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0x2de0/0x3cb0 kernel/locking/lockdep.c:5007 Read of size 8 at addr ffff888061e6d818 by task syz-executor/10357 CPU: 0 UID: 0 PID: 10357 Comm: syz-executor Not tainted 6.11.0-rc7-syzkaller-00020-g8d8d276ba2fb #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:lock_acquire+0x1f2/0x560 kernel/locking/lockdep.c:5727 Code: c1 05 5a 37 99 7e 83 f8 01 0f 85 ea 02 00 00 9c 58 f6 c4 02 0f 85 d5 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0000:ffffc90027f178c8 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff92004fe2f1b RCX: 0000000000000001 RDX: 0000000000000001 RSI: ffffffff8b4cd360 RDI: ffffffff8bb08060 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff2d126e0 R10: ffffffff96893707 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8ddb94a0 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:326 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] page_ext_get+0x3a/0x310 mm/page_ext.c:525 page_table_check_set mm/page_table_check.c:114 [inline] page_table_check_set+0x285/0x9d0 mm/page_table_check.c:102 __page_table_check_ptes_set+0x2d0/0x3e0 mm/page_table_check.c:225 page_table_check_ptes_set include/linux/page_table_check.h:74 [inline] set_ptes include/linux/pgtable.h:267 [inline] set_pte_range+0x30e/0x520 mm/memory.c:4806 filemap_map_order0_folio mm/filemap.c:3594 [inline] filemap_map_pages+0x50e/0x1440 mm/filemap.c:3644 do_fault_around mm/memory.c:5019 [inline] do_read_fault mm/memory.c:5052 [inline] do_fault mm/memory.c:5191 [inline] do_pte_missing mm/memory.c:3947 [inline] handle_pte_fault mm/memory.c:5521 [inline] __handle_mm_fault+0x39de/0x5400 mm/memory.c:5664 handle_mm_fault+0x498/0xa60 mm/memory.c:5832 do_user_addr_fault+0x60d/0x13f0 arch/x86/mm/fault.c:1338 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 RIP: 0023:0xf71e76d0 Code: 77 ff ff 83 c4 10 eb d3 66 90 83 ec 0c 8d 83 24 d5 b6 00 50 e8 e1 77 ff ff 83 c4 10 eb d4 8d b4 26 00 00 00 00 8d 74 26 00 90 a4 1b ef ff 81 c2 1f 49 1d 00 80 ba 20 d5 b6 00 00 74 7c c7 c0 RSP: 002b:00000000ffba031c EFLAGS: 00010282 RAX: 00000000f7f294c0 RBX: 00000000f73bbff4 RCX: 00000000f71e76d0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00000000f73bbff4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 10356: 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 10356: 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 ffff888061e6d800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 24 bytes inside of freed 512-byte region [ffff888061e6d800, ffff888061e6da00) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x61e6c head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0x4fff00000000040(head|node=1|zone=1|lastcpupid=0x7ff) page_type: 0xfdffffff(slab) raw: 04fff00000000040 ffff88801ac42c80 0000000000000000 dead000000000001 raw: 0000000000000000 0000000080100010 00000001fdffffff 0000000000000000 head: 04fff00000000040 ffff88801ac42c80 0000000000000000 dead000000000001 head: 0000000000000000 0000000080100010 00000001fdffffff 0000000000000000 head: 04fff00000000002 ffffea0001879b01 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5358, tgid 5358 (syz-executor), ts 104418445062, free_ts 0 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_add_mroute+0x1de/0x350 net/ipv6/addrconf.c:2550 addrconf_add_dev+0x14e/0x1c0 net/ipv6/addrconf.c:2568 inet6_addr_add+0x1a8/0xbc0 net/ipv6/addrconf.c:3024 inet6_rtm_newaddr+0x11d4/0x1aa0 net/ipv6/addrconf.c:5048 rtnetlink_rcv_msg+0x3c7/0xea0 net/core/rtnetlink.c:6647 page_owner free stack trace missing Memory state around the buggy address: ffff888061e6d700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888061e6d780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888061e6d800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888061e6d880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888061e6d900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: c1 05 5a 37 99 7e 83 roll $0x83,0x7e99375a(%rip) # 0x7e993761 7: f8 clc 8: 01 0f add %ecx,(%rdi) a: 85 ea test %ebp,%edx c: 02 00 add (%rax),%al e: 00 9c 58 f6 c4 02 0f add %bl,0xf02c4f6(%rax,%rbx,2) 15: 85 d5 test %edx,%ebp 17: 02 00 add (%rax),%al 19: 00 48 85 add %cl,-0x7b(%rax) 1c: ed in (%dx),%eax 1d: 74 01 je 0x20 1f: fb sti 20: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 27: fc ff df * 2a: 48 01 c3 add %rax,%rbx <-- trapping instruction 2d: 48 c7 03 00 00 00 00 movq $0x0,(%rbx) 34: 48 c7 43 08 00 00 00 movq $0x0,0x8(%rbx) 3b: 00 3c: 48 rex.W 3d: 8b .byte 0x8b 3e: 84 .byte 0x84 3f: 24 .byte 0x24