================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0x2dfe/0x3ce0 kernel/locking/lockdep.c:5062 Read of size 8 at addr ffff8880254f0c18 by task vivid-000-vid-c/5916 CPU: 3 UID: 0 PID: 5916 Comm: vivid-000-vid-c Not tainted 6.11.0-syzkaller-11993-g3efc57369a0c #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:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 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+0x2dfe/0x3ce0 kernel/locking/lockdep.c:5062 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5822 __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+0xba/0xe0 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 RIP: 0010:__schedule+0xefd/0x5750 kernel/sched/core.c:6533 Code: fa 48 c1 ea 03 80 3c 02 00 0f 85 29 45 00 00 48 8b bd 10 ff ff ff 4d 89 67 10 4c 89 e6 e8 bb d5 dd f5 48 89 c7 e8 63 4b 3a f6 <48> 8b b5 98 fe ff ff 48 b8 00 00 00 00 00 fc ff df 48 01 c6 48 c7 RSP: 0018:ffffc90003ccfc40 EFLAGS: 00000202 RAX: 000000000009abbf RBX: ffff888026f54880 RCX: 1ffffffff20bdcc9 RDX: 0000000000000000 RSI: ffffffff8b6cd040 RDI: ffffffff8bd19b00 RBP: ffffc90003ccfdd8 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff905f288f R11: 0000000000000001 R12: ffff88806a93fa08 R13: 0000000000000000 R14: 0000000000000000 R15: ffff88806a93ee80 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6767 vivid_thread_vid_cap+0x6c9/0xb90 drivers/media/test-drivers/vivid/vivid-kthread-cap.c:794 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 5937: 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:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kmalloc_noprof include/linux/slab.h:878 [inline] p9_client_create+0xc8/0x11b0 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:3507 [inline] path_mount+0x14e6/0x1f20 fs/namespace.c:3834 do_mount fs/namespace.c:3847 [inline] __do_sys_mount fs/namespace.c:4055 [inline] __se_sys_mount fs/namespace.c:4032 [inline] __x64_sys_mount+0x294/0x320 fs/namespace.c:4032 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5937: 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 mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:2343 [inline] slab_free mm/slub.c:4580 [inline] kfree+0x14f/0x4b0 mm/slub.c:4728 p9_client_create+0xa58/0x11b0 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:3507 [inline] path_mount+0x14e6/0x1f20 fs/namespace.c:3834 do_mount fs/namespace.c:3847 [inline] __do_sys_mount fs/namespace.c:4055 [inline] __se_sys_mount fs/namespace.c:4032 [inline] __x64_sys_mount+0x294/0x320 fs/namespace.c:4032 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880254f0c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 24 bytes inside of freed 512-byte region [ffff8880254f0c00, ffff8880254f0e00) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x254f0 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: f5(slab) raw: 00fff00000000040 ffff88801b042c80 dead000000000100 dead000000000122 raw: 0000000000000000 0000000080100010 00000001f5000000 0000000000000000 head: 00fff00000000040 ffff88801b042c80 dead000000000100 dead000000000122 head: 0000000000000000 0000000080100010 00000001f5000000 0000000000000000 head: 00fff00000000002 ffffea0000953c01 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 82, tgid 82 (kworker/u32:4), ts 40087288758, free_ts 40049606636 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1545 [inline] get_page_from_freelist+0x101e/0x3070 mm/page_alloc.c:3457 __alloc_pages_noprof+0x223/0x25c0 mm/page_alloc.c:4733 alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265 alloc_slab_page mm/slub.c:2413 [inline] allocate_slab mm/slub.c:2579 [inline] new_slab+0x2ba/0x3f0 mm/slub.c:2632 ___slab_alloc+0xdac/0x1880 mm/slub.c:3819 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3909 __slab_alloc_node mm/slub.c:3962 [inline] slab_alloc_node mm/slub.c:4123 [inline] __kmalloc_cache_noprof+0x2b4/0x300 mm/slub.c:4291 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] mca_alloc net/ipv6/mcast.c:881 [inline] __ipv6_dev_mc_inc+0x2b7/0xc10 net/ipv6/mcast.c:937 addrconf_join_solict net/ipv6/addrconf.c:2241 [inline] addrconf_dad_begin net/ipv6/addrconf.c:4104 [inline] addrconf_dad_work+0x232/0x14d0 net/ipv6/addrconf.c:4229 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 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 page last free pid 5335 tgid 5335 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1108 [inline] free_unref_page+0x5f4/0xdc0 mm/page_alloc.c:2638 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4086 [inline] slab_alloc_node mm/slub.c:4135 [inline] __do_kmalloc_node mm/slub.c:4264 [inline] __kmalloc_noprof+0x199/0x400 mm/slub.c:4277 kmalloc_noprof include/linux/slab.h:882 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] fib6_info_alloc+0x40/0x160 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x337/0x1910 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 addrconf_dev_config net/ipv6/addrconf.c:3484 [inline] addrconf_init_auto_addrs+0x380/0x820 net/ipv6/addrconf.c:3572 addrconf_notify+0x6e2/0x19c0 net/ipv6/addrconf.c:3745 notifier_call_chain+0xb9/0x410 kernel/notifier.c:93 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1996 netdev_state_change net/core/dev.c:1378 [inline] netdev_state_change+0x115/0x150 net/core/dev.c:1371 netdev_set_operstate+0x104/0x150 net/core/rtnetlink.c:854 Memory state around the buggy address: ffff8880254f0b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880254f0b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880254f0c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880254f0c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880254f0d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: fa cli 1: 48 c1 ea 03 shr $0x3,%rdx 5: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 9: 0f 85 29 45 00 00 jne 0x4538 f: 48 8b bd 10 ff ff ff mov -0xf0(%rbp),%rdi 16: 4d 89 67 10 mov %r12,0x10(%r15) 1a: 4c 89 e6 mov %r12,%rsi 1d: e8 bb d5 dd f5 call 0xf5ddd5dd 22: 48 89 c7 mov %rax,%rdi 25: e8 63 4b 3a f6 call 0xf63a4b8d * 2a: 48 8b b5 98 fe ff ff mov -0x168(%rbp),%rsi <-- trapping instruction 31: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 38: fc ff df 3b: 48 01 c6 add %rax,%rsi 3e: 48 rex.W 3f: c7 .byte 0xc7