================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0x2de0/0x3cb0 kernel/locking/lockdep.c:5007 Read of size 8 at addr ffff888028224418 by task syz.0.4203/13936 CPU: 3 UID: 0 PID: 13936 Comm: syz.0.4203 Not tainted 6.11.0-rc7-syzkaller-00145-g57719771a244 #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+0x52/0xd0 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 RIP: 0010:write_comp_data+0x8b/0x90 kernel/kcov.c:271 Code: 00 00 4a 8d 34 dd 28 00 00 00 48 39 f2 72 1b 48 83 c7 01 48 89 38 4c 89 44 30 e0 4c 89 4c 30 e8 4c 89 54 30 f0 4a 89 4c d8 20 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 RSP: 0018:ffffc90000908718 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc900009087a0 RCX: ffffffff813cef46 RDX: ffff88803468c880 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffc900009087a0 R13: ffffffff81776c00 R14: ffffc90000908860 R15: ffff88803468c880 unwind_next_frame+0x46/0x23a0 arch/x86/kernel/unwind_orc.c:475 arch_stack_walk+0x100/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 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] kmem_cache_free+0x12f/0x3a0 mm/slub.c:4552 skb_kfree_head net/core/skbuff.c:1082 [inline] skb_kfree_head net/core/skbuff.c:1079 [inline] skb_free_head+0x18a/0x1d0 net/core/skbuff.c:1096 skb_release_data+0x75c/0x980 net/core/skbuff.c:1123 skb_release_all net/core/skbuff.c:1188 [inline] __kfree_skb net/core/skbuff.c:1202 [inline] consume_skb net/core/skbuff.c:1426 [inline] consume_skb+0xd0/0x160 net/core/skbuff.c:1420 mac80211_hwsim_tx_frame+0x1f3/0x2a0 drivers/net/wireless/virtual/mac80211_hwsim.c:2216 __mac80211_hwsim_beacon_tx drivers/net/wireless/virtual/mac80211_hwsim.c:2232 [inline] mac80211_hwsim_beacon_tx+0x592/0xa00 drivers/net/wireless/virtual/mac80211_hwsim.c:2315 __iterate_interfaces+0x2d0/0x5d0 net/mac80211/util.c:772 ieee80211_iterate_active_interfaces_atomic+0x71/0x1b0 net/mac80211/util.c:808 mac80211_hwsim_beacon+0x105/0x200 drivers/net/wireless/virtual/mac80211_hwsim.c:2345 __run_hrtimer kernel/time/hrtimer.c:1689 [inline] __hrtimer_run_queues+0x20c/0xcc0 kernel/time/hrtimer.c:1753 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1770 handle_softirqs+0x216/0x8f0 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:637 [inline] irq_exit_rcu+0xbb/0x120 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:124 [inline] RIP: 0010:rcu_is_watching+0x41/0xc0 kernel/rcu/tree.c:726 Code: 03 00 83 f8 07 89 c5 0f 87 82 00 00 00 48 8d 3c ed 80 ab 7c 8d 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <75> 5c 48 03 1c ed 80 ab 7c 8d 48 b8 00 00 00 00 00 fc ff df 48 89 RSP: 0018:ffffc90006a6f528 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: 0000000000037ec8 RCX: ffffffff8169c0b9 RDX: 1ffffffff1af9573 RSI: ffffffff8bb0fb80 RDI: ffffffff8d7cab98 RBP: 0000000000000003 R08: 0000000000000000 R09: fffffbfff20289b3 R10: ffffffff90144d9f R11: 0000000000000000 R12: ffffffff8ddb9f20 R13: 0000000000000008 R14: 000000000003db0c R15: ffffc90006a6fab8 trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x4f6/0x6f0 kernel/locking/lockdep.c:5770 rcu_lock_release include/linux/rcupdate.h:336 [inline] rcu_read_unlock_sched include/linux/rcupdate.h:951 [inline] pfn_valid include/linux/mmzone.h:2032 [inline] page_table_check_clear mm/page_table_check.c:70 [inline] __page_table_check_pte_clear+0x2d9/0x580 mm/page_table_check.c:169 page_table_check_pte_clear include/linux/page_table_check.h:49 [inline] ptep_get_and_clear_full arch/x86/include/asm/pgtable.h:1284 [inline] get_and_clear_full_ptes include/linux/pgtable.h:678 [inline] zap_present_folio_ptes mm/memory.c:1493 [inline] zap_present_ptes mm/memory.c:1576 [inline] zap_pte_range mm/memory.c:1618 [inline] zap_pmd_range mm/memory.c:1736 [inline] zap_pud_range mm/memory.c:1765 [inline] zap_p4d_range mm/memory.c:1786 [inline] unmap_page_range+0x228a/0x3d30 mm/memory.c:1807 unmap_single_vma+0x194/0x2b0 mm/memory.c:1853 unmap_vmas+0x22f/0x490 mm/memory.c:1897 exit_mmap+0x1b8/0xb20 mm/mmap.c:3412 __mmput+0x12a/0x480 kernel/fork.c:1345 mmput+0x62/0x70 kernel/fork.c:1367 exit_mm kernel/exit.c:571 [inline] do_exit+0x9bf/0x2bb0 kernel/exit.c:869 do_group_exit+0xd3/0x2a0 kernel/exit.c:1031 get_signal+0x25fb/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f90cd97def9 Code: Unable to access opcode bytes at 0x7f90cd97decf. RSP: 002b:00007f90ce8330e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f90cdb35f88 RCX: 00007f90cd97def9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f90cdb35f88 RBP: 00007f90cdb35f80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f90cdb35f8c R13: 0000000000000000 R14: 00007fff9083a990 R15: 00007fff9083aa78 Allocated by task 13934: 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/0x1210 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+0x14e6/0x1f20 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] __x64_sys_mount+0x294/0x320 fs/namespace.c:3997 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 13934: 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+0xaaa/0x1210 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+0x14e6/0x1f20 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] __x64_sys_mount+0x294/0x320 fs/namespace.c:3997 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 ffff888028224400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 24 bytes inside of freed 512-byte region [ffff888028224400, ffff888028224600) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x28224 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xfdffffff(slab) raw: 00fff00000000040 ffff88801ac42c80 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000100010 00000001fdffffff 0000000000000000 head: 00fff00000000040 ffff88801ac42c80 0000000000000000 dead000000000001 head: 0000000000000000 0000000000100010 00000001fdffffff 0000000000000000 head: 00fff00000000002 ffffea0000a08901 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 4834, tgid 4834 (udevd), ts 46814742872, free_ts 46802483756 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] __kmalloc_cache_noprof+0x2b4/0x300 mm/slub.c:4188 kmalloc_noprof include/linux/slab.h:681 [inline] kzalloc_noprof include/linux/slab.h:807 [inline] kernfs_fop_open+0x28b/0xdb0 fs/kernfs/file.c:623 do_dentry_open+0x91f/0x15f0 fs/open.c:959 vfs_open+0x82/0x3f0 fs/open.c:1089 do_open fs/namei.c:3727 [inline] path_openat+0x2141/0x2d20 fs/namei.c:3886 do_filp_open+0x1dc/0x430 fs/namei.c:3913 do_sys_openat2+0x17a/0x1e0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_openat fs/open.c:1447 [inline] __se_sys_openat fs/open.c:1442 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1442 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 page last free pid 4834 tgid 4834 stack trace: create_dummy_stack mm/page_owner.c:94 [inline] register_dummy_stack+0x8a/0xd0 mm/page_owner.c:100 init_page_owner+0x48/0xc00 mm/page_owner.c:118 invoke_init_callbacks mm/page_ext.c:148 [inline] page_ext_init+0x6b8/0xab0 mm/page_ext.c:497 mm_core_init+0x12d/0x220 mm/mm_init.c:2673 Memory state around the buggy address: ffff888028224300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888028224380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888028224400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888028224480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888028224500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 4a 8d 34 dd 28 00 00 lea 0x28(,%r11,8),%rsi 9: 00 a: 48 39 f2 cmp %rsi,%rdx d: 72 1b jb 0x2a f: 48 83 c7 01 add $0x1,%rdi 13: 48 89 38 mov %rdi,(%rax) 16: 4c 89 44 30 e0 mov %r8,-0x20(%rax,%rsi,1) 1b: 4c 89 4c 30 e8 mov %r9,-0x18(%rax,%rsi,1) 20: 4c 89 54 30 f0 mov %r10,-0x10(%rax,%rsi,1) 25: 4a 89 4c d8 20 mov %rcx,0x20(%rax,%r11,8) * 2a: c3 ret <-- trapping instruction 2b: cc int3 2c: cc int3 2d: cc int3 2e: cc int3 2f: 90 nop 30: 90 nop 31: 90 nop 32: 90 nop 33: 90 nop 34: 90 nop 35: 90 nop 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: f3 repz