================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x3ee7/0x56d0 kernel/locking/lockdep.c:4923 Read of size 8 at addr ffff888025227018 by task syz-fuzzer/3803 CPU: 1 PID: 3803 Comm: syz-fuzzer Not tainted 6.0.0-rc4-syzkaller-00062-g0066f1b0e275 #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 __lock_acquire+0x3ee7/0x56d0 kernel/locking/lockdep.c:4923 lock_acquire kernel/locking/lockdep.c:5666 [inline] lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5631 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 p9_tag_remove net/9p/client.c:367 [inline] p9_req_put net/9p/client.c:375 [inline] p9_req_put+0xc6/0x250 net/9p/client.c:372 req_done+0x1de/0x2e0 net/9p/trans_virtio.c:148 vring_interrupt drivers/virtio/virtio_ring.c:2462 [inline] vring_interrupt+0x29d/0x3d0 drivers/virtio/virtio_ring.c:2437 __handle_irq_event_percpu+0x227/0x870 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xa7/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x25f/0xd00 kernel/irq/chip.c:819 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline] handle_irq arch/x86/kernel/irq.c:231 [inline] __common_interrupt+0x9d/0x210 arch/x86/kernel/irq.c:250 common_interrupt+0x4d/0xc0 arch/x86/kernel/irq.c:240 asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:640 RIP: 0033:0x4fa16a Code: 94 24 80 00 00 00 4c 8b 52 38 48 8b 4a 40 48 8b 44 24 58 48 39 c8 0f 8d c9 fb ff ff 0f 1f 40 00 0f 83 4c 04 00 00 48 8d 34 80 <4d> 8b 04 f2 4c 89 84 24 f0 00 00 00 4d 8d 04 f2 4d 8d 40 08 41 0f RSP: 002b:000000c000c35430 EFLAGS: 00010297 RAX: 0000000000000000 RBX: 0000000000000072 RCX: 0000000000000006 RDX: 0000000001344500 RSI: 0000000000000000 RDI: 000000c00242e9f0 RBP: 000000c000c35548 R08: 000000c014561bc0 R09: 000000c01656b180 R10: 00000000014beda0 R11: 0000000000000000 R12: 0000000000203003 R13: 0000000000835af8 R14: 000000c0000001a0 R15: 00007fdca9886cf4 Allocated by task 4250: 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:600 [inline] p9_client_create+0xaf/0x1070 net/9p/client.c:934 v9fs_session_init+0x1e2/0x1810 fs/9p/v9fs.c:408 v9fs_mount+0xba/0xc90 fs/9p/vfs_super.c:126 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1530 do_new_mount fs/namespace.c:3040 [inline] path_mount+0x1326/0x1e20 fs/namespace.c:3370 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount fs/namespace.c:3568 [inline] __ia32_sys_mount+0x27e/0x300 fs/namespace.c:3568 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 4250: 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:1754 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1780 slab_free mm/slub.c:3534 [inline] kfree+0xe2/0x580 mm/slub.c:4562 p9_client_create+0x7a6/0x1070 net/9p/client.c:1005 v9fs_session_init+0x1e2/0x1810 fs/9p/v9fs.c:408 v9fs_mount+0xba/0xc90 fs/9p/vfs_super.c:126 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1530 do_new_mount fs/namespace.c:3040 [inline] path_mount+0x1326/0x1e20 fs/namespace.c:3370 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount fs/namespace.c:3568 [inline] __ia32_sys_mount+0x27e/0x300 fs/namespace.c:3568 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 ffff888025227000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 24 bytes inside of 512-byte region [ffff888025227000, ffff888025227200) The buggy address belongs to the physical page: page:ffffea0000948900 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x25224 head:ffffea0000948900 order:2 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888011842c80 raw: 0000000000000000 0000000080100010 00000001ffffffff 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 3703, tgid 3703 (syz-executor.0), ts 234360964234, free_ts 58456870600 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:5515 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:1824 [inline] allocate_slab+0x27e/0x3d0 mm/slub.c:1969 new_slab mm/slub.c:2029 [inline] ___slab_alloc+0x7f1/0xe10 mm/slub.c:3031 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3118 slab_alloc_node mm/slub.c:3209 [inline] __kmalloc_node_track_caller+0x2f2/0x380 mm/slub.c:4955 kmalloc_reserve net/core/skbuff.c:358 [inline] __alloc_skb+0xd9/0x2f0 net/core/skbuff.c:430 alloc_skb include/linux/skbuff.h:1257 [inline] alloc_uevent_skb+0x7b/0x210 lib/kobject_uevent.c:290 uevent_net_broadcast_tagged lib/kobject_uevent.c:351 [inline] kobject_uevent_net_broadcast lib/kobject_uevent.c:412 [inline] kobject_uevent_env+0x110a/0x1640 lib/kobject_uevent.c:593 device_add+0xb72/0x1e90 drivers/base/core.c:3498 netdev_register_kobject+0x181/0x400 net/core/net-sysfs.c:2015 register_netdevice+0xe01/0x1680 net/core/dev.c:10070 hsr_dev_finalize+0x506/0x7d0 net/hsr/hsr_device.c:539 hsr_newlink+0x315/0x730 net/hsr/hsr_netlink.c:102 rtnl_newlink_create net/core/rtnetlink.c:3363 [inline] __rtnl_newlink+0x1087/0x17e0 net/core/rtnetlink.c:3580 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 __unfreeze_partials+0x17c/0x1a0 mm/slub.c:2548 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:447 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:727 [inline] slab_alloc_node mm/slub.c:3243 [inline] __kmalloc_node+0x2a9/0x380 mm/slub.c:4468 kmalloc_node include/linux/slab.h:623 [inline] kvmalloc_node+0x3e/0x190 mm/util.c:613 kvmalloc include/linux/slab.h:750 [inline] seq_buf_alloc fs/seq_file.c:38 [inline] seq_read_iter+0x7f7/0x1280 fs/seq_file.c:210 proc_reg_read_iter+0x1fb/0x2d0 fs/proc/inode.c:305 call_read_iter include/linux/fs.h:2181 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x67d/0x930 fs/read_write.c:470 ksys_read+0x127/0x250 fs/read_write.c:607 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff888025226f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888025226f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888025227000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888025227080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888025227100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================