================================================================== BUG: KASAN: slab-use-after-free in __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] BUG: KASAN: slab-use-after-free in _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166 Read of size 1 at addr ffff88802be8e068 by task syz.7.333/8125 CPU: 0 UID: 0 PID: 8125 Comm: syz.7.333 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 __kasan_check_byte+0x2a/0x40 mm/kasan/common.c:574 kasan_check_byte include/linux/kasan.h:402 [inline] lock_acquire+0x84/0x350 kernel/locking/lockdep.c:5844 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166 rt_mutex_slowunlock+0xbf/0x8b0 kernel/locking/rtmutex.c:1426 spin_unlock include/linux/spinlock_rt.h:109 [inline] class_spinlock_destructor include/linux/spinlock.h:587 [inline] dma_buf_fd+0x178/0x330 drivers/dma-buf/dma-buf.c:796 udmabuf_create+0xf26/0xfe0 drivers/dma-buf/udmabuf.c:453 udmabuf_ioctl_create drivers/dma-buf/udmabuf.c:484 [inline] udmabuf_ioctl+0x1f6/0x310 drivers/dma-buf/udmabuf.c:515 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xff/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd93168c819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd92f89c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fd931906180 RCX: 00007fd93168c819 RDX: 0000200000000000 RSI: 0000000040187542 RDI: 0000000000000006 RBP: 00007fd931722c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd931906218 R14: 00007fd931906180 R15: 00007ffe4322fd18 Allocated by task 8125: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5295 [inline] __kmalloc_noprof+0x3e7/0x7b0 mm/slub.c:5307 kmalloc_noprof include/linux/slab.h:954 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] dma_buf_export+0x3ba/0xad0 drivers/dma-buf/dma-buf.c:739 export_udmabuf drivers/dma-buf/udmabuf.c:320 [inline] udmabuf_create+0xee5/0xfe0 drivers/dma-buf/udmabuf.c:442 udmabuf_ioctl_create drivers/dma-buf/udmabuf.c:484 [inline] udmabuf_ioctl+0x1f6/0x310 drivers/dma-buf/udmabuf.c:515 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xff/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 8126: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2689 [inline] slab_free mm/slub.c:6246 [inline] kfree+0x1c5/0x6c0 mm/slub.c:6561 __dentry_kill+0x211/0x690 fs/dcache.c:723 finish_dput+0xc9/0x480 fs/dcache.c:927 __fput+0x6a3/0xa70 fs/file_table.c:518 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline] do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88802be8e000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 104 bytes inside of freed 1024-byte region [ffff88802be8e000, ffff88802be8e400) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2be88 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff88801a02cdc0 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000 head: 0080000000000040 ffff88801a02cdc0 dead000000000100 dead000000000122 head: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000 head: 0080000000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6099, tgid 6099 (kworker/u8:17), ts 193857129425, free_ts 193798974250 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1858 prep_new_page mm/page_alloc.c:1866 [inline] get_page_from_freelist+0x27d6/0x2850 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5226 alloc_slab_page mm/slub.c:3278 [inline] allocate_slab+0x77/0x660 mm/slub.c:3467 new_slab mm/slub.c:3525 [inline] refill_objects+0x33c/0x3d0 mm/slub.c:7251 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x373/0x720 mm/slub.c:4651 alloc_from_pcs mm/slub.c:4749 [inline] slab_alloc_node mm/slub.c:4883 [inline] __do_kmalloc_node mm/slub.c:5294 [inline] __kmalloc_noprof+0x530/0x7b0 mm/slub.c:5307 kmalloc_noprof include/linux/slab.h:954 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] ieee802_11_parse_elems_full+0x159/0x2ab0 net/mac80211/parse.c:1051 ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2518 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1565 [inline] ieee80211_ibss_rx_queued_mgmt+0x4ca/0x2cb0 net/mac80211/ibss.c:1596 ieee80211_iface_process_skb net/mac80211/iface.c:1795 [inline] ieee80211_iface_work+0x845/0x1390 net/mac80211/iface.c:1849 cfg80211_wiphy_work+0x2cf/0x460 net/wireless/core.c:513 process_one_work kernel/workqueue.c:3308 [inline] process_scheduled_works+0xb68/0x1910 kernel/workqueue.c:3399 worker_thread+0xa90/0x1040 kernel/workqueue.c:3485 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 page last free pid 5834 tgid 5834 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1402 [inline] __free_frozen_pages+0xf9b/0x10f0 mm/page_alloc.c:2943 __slab_free+0x252/0x2a0 mm/slub.c:5608 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4569 [inline] slab_alloc_node mm/slub.c:4898 [inline] kmem_cache_alloc_noprof+0x33b/0x680 mm/slub.c:4905 alloc_filename fs/namei.c:142 [inline] do_getname+0x2e/0x250 fs/namei.c:182 getname_flags fs/namei.c:225 [inline] class_filename_flags_constructor include/linux/fs.h:2562 [inline] user_path_at+0x2a/0x160 fs/namei.c:3642 ksys_umount fs/namespace.c:2062 [inline] __do_sys_umount fs/namespace.c:2070 [inline] __se_sys_umount fs/namespace.c:2068 [inline] __x64_sys_umount+0xf6/0x170 fs/namespace.c:2068 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88802be8df00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802be8df80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88802be8e000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802be8e080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802be8e100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================