================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0x2de0/0x3cb0 kernel/locking/lockdep.c:5007 Read of size 8 at addr ffff888045cef418 by task swapper/3/0 CPU: 3 UID: 0 PID: 0 Comm: swapper/3 Not tainted 6.11.0-rc5-syzkaller-00219-g1934261d8974 #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:handle_softirqs+0x1da/0x8f0 kernel/softirq.c:540 Code: 89 44 24 18 48 89 6c 24 10 48 c7 c7 e0 76 4b 8b e8 9b ce c6 09 65 66 c7 05 99 d5 b3 7e 00 00 e8 3c 06 43 00 fb bb ff ff ff ff <49> c7 c6 c0 a0 a0 8d 41 0f bc dc 83 c3 01 0f 85 a7 00 00 00 e9 b4 RSP: 0018:ffffc90000908f30 EFLAGS: 00000206 RAX: 000000000180fce2 RBX: 00000000ffffffff RCX: 1ffffffff2027f91 RDX: 0000000000000000 RSI: ffffffff8b4cd740 RDI: ffffffff8bb0f900 RBP: ffff88801d6da440 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff901440df R11: 0000000000000000 R12: 0000000000000380 R13: 000000000000000a R14: 0000000000000001 R15: 0000000000000000 __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:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:92 [inline] RIP: 0010:default_idle+0xf/0x20 arch/x86/kernel/process.c:743 Code: 4c 01 c7 4c 29 c2 e9 72 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d d3 b8 2f 00 fb f4 c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 RSP: 0018:ffffc900001a7e08 EFLAGS: 00000246 RAX: 000000000180fcdd RBX: 0000000000000003 RCX: ffffffff8b16cb79 RDX: 0000000000000000 RSI: ffffffff8b4cd740 RDI: ffffffff8bb0f900 RBP: ffffed1003adb488 R08: 0000000000000001 R09: ffffed100d526fd9 R10: ffff88806a937ecb R11: 0000000000000000 R12: 0000000000000003 R13: ffff88801d6da440 R14: ffffffff901440d8 R15: 0000000000000000 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x32c/0x3f0 kernel/sched/idle.c:326 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:424 start_secondary+0x220/0x2b0 arch/x86/kernel/smpboot.c:313 common_startup_64+0x13e/0x148 Allocated by task 5267: 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 5267: 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:2252 [inline] slab_free mm/slub.c:4473 [inline] kfree+0x12a/0x3b0 mm/slub.c:4594 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 ffff888045cef400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 24 bytes inside of freed 512-byte region [ffff888045cef400, ffff888045cef600) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888045cee400 pfn:0x45cec 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: ffff888045cee400 000000008010000e 00000001fdffffff 0000000000000000 head: 00fff00000000040 ffff88801ac42c80 0000000000000000 dead000000000001 head: ffff888045cee400 000000008010000e 00000001fdffffff 0000000000000000 head: 00fff00000000002 ffffea0001173b01 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 831, tgid 831 (kworker/2:2), ts 416594154166, free_ts 408490911242 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1493 prep_new_page mm/page_alloc.c:1501 [inline] get_page_from_freelist+0x1351/0x2e50 mm/page_alloc.c:3439 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4695 __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:2321 allocate_slab mm/slub.c:2484 [inline] new_slab+0x84/0x260 mm/slub.c:2537 ___slab_alloc+0xdac/0x1870 mm/slub.c:3723 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3813 __slab_alloc_node mm/slub.c:3866 [inline] slab_alloc_node mm/slub.c:4025 [inline] __kmalloc_cache_noprof+0x2b4/0x300 mm/slub.c:4184 kmalloc_noprof include/linux/slab.h:681 [inline] kzalloc_noprof include/linux/slab.h:807 [inline] drm_atomic_helper_setup_commit+0x633/0x15e0 drivers/gpu/drm/drm_atomic_helper.c:2289 drm_atomic_helper_commit+0xa9/0x380 drivers/gpu/drm/drm_atomic_helper.c:2023 drm_atomic_commit+0x229/0x300 drivers/gpu/drm/drm_atomic.c:1522 drm_atomic_helper_dirtyfb+0x60d/0x790 drivers/gpu/drm/drm_damage_helper.c:181 drm_fbdev_shmem_helper_fb_dirty+0x1c9/0x330 drivers/gpu/drm/drm_fbdev_shmem.c:197 drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:383 [inline] drm_fb_helper_damage_work+0x285/0x5e0 drivers/gpu/drm/drm_fb_helper.c:406 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389 page last free pid 5401 tgid 5401 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1094 [inline] free_unref_page+0x64a/0xe40 mm/page_alloc.c:2612 __folio_put+0x31c/0x3e0 mm/swap.c:128 folio_put_refs include/linux/mm.h:1506 [inline] gup_put_folio+0x21a/0x2a0 mm/gup.c:115 unpin_user_pages_dirty_lock+0x223/0x4e0 mm/gup.c:325 xdp_umem_unpin_pages net/xdp/xdp_umem.c:26 [inline] xdp_umem_release net/xdp/xdp_umem.c:61 [inline] xdp_put_umem+0x1ab/0x470 net/xdp/xdp_umem.c:89 xp_release_deferred+0x14e/0x220 net/xdp/xsk_buff_pool.c:289 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389 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 Memory state around the buggy address: ffff888045cef300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888045cef380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888045cef400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888045cef480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888045cef500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 89 44 24 18 mov %eax,0x18(%rsp) 4: 48 89 6c 24 10 mov %rbp,0x10(%rsp) 9: 48 c7 c7 e0 76 4b 8b mov $0xffffffff8b4b76e0,%rdi 10: e8 9b ce c6 09 call 0x9c6ceb0 15: 65 66 c7 05 99 d5 b3 movw $0x0,%gs:0x7eb3d599(%rip) # 0x7eb3d5b8 1c: 7e 00 00 1f: e8 3c 06 43 00 call 0x430660 24: fb sti 25: bb ff ff ff ff mov $0xffffffff,%ebx * 2a: 49 c7 c6 c0 a0 a0 8d mov $0xffffffff8da0a0c0,%r14 <-- trapping instruction 31: 41 0f bc dc bsf %r12d,%ebx 35: 83 c3 01 add $0x1,%ebx 38: 0f 85 a7 00 00 00 jne 0xe5 3e: e9 .byte 0xe9 3f: b4 .byte 0xb4