================================================================== BUG: KASAN: slab-out-of-bounds in copy_to_urb+0x261/0x460 sound/usb/pcm.c:1487 Write of size 264 at addr ffff888059753e00 by task syz.5.4033/22163 CPU: 1 UID: 0 PID: 22163 Comm: syz.5.4033 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:200 __asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106 copy_to_urb+0x261/0x460 sound/usb/pcm.c:1487 prepare_playback_urb+0x953/0x13d0 sound/usb/pcm.c:1611 prepare_outbound_urb+0x377/0xc50 sound/usb/endpoint.c:333 snd_usb_endpoint_start+0x4db/0x1530 sound/usb/endpoint.c:1596 start_endpoints+0xa1/0x280 sound/usb/pcm.c:291 snd_usb_substream_playback_trigger+0x3e0/0x830 sound/usb/pcm.c:1711 snd_pcm_do_start+0xb7/0x180 sound/core/pcm_native.c:1454 snd_pcm_action_single sound/core/pcm_native.c:1310 [inline] snd_pcm_action+0xe7/0x240 sound/core/pcm_native.c:1393 __snd_pcm_lib_xfer+0x1762/0x1d00 sound/core/pcm_lib.c:2405 snd_pcm_oss_write3+0x1bc/0x350 sound/core/oss/pcm_oss.c:1241 snd_pcm_plug_write_transfer+0x2cb/0x4c0 sound/core/oss/pcm_plugin.c:630 snd_pcm_oss_write2 sound/core/oss/pcm_oss.c:1373 [inline] snd_pcm_oss_sync1+0x2f6/0x760 sound/core/oss/pcm_oss.c:1615 snd_pcm_oss_sync+0x6ef/0x9d0 sound/core/oss/pcm_oss.c:1680 snd_pcm_oss_release+0xff/0x250 sound/core/oss/pcm_oss.c:2573 __fput+0x44c/0xa70 fs/file_table.c:468 task_work_run+0x1d4/0x260 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:44 [inline] exit_to_user_mode_loop+0xef/0x4e0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2b7/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2b6c18f749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2b6d0cb038 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f2b6c3e6090 RCX: 00007f2b6c18f749 RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 000000000000000a RBP: 00007f2b6c213f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2b6c3e6128 R14: 00007f2b6c3e6090 R15: 00007f2b6c50fa28 Allocated by task 22163: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5657 [inline] __kmalloc_noprof+0x41d/0x800 mm/slub.c:5669 data_ep_set_params sound/usb/endpoint.c:1242 [inline] snd_usb_endpoint_set_params+0x1741/0x2f10 sound/usb/endpoint.c:1379 snd_usb_hw_params+0xb12/0x12e0 sound/usb/pcm.c:576 snd_pcm_hw_params+0x89d/0x1d30 sound/core/pcm_native.c:804 snd_pcm_oss_change_params_locked+0x21cd/0x3f70 sound/core/oss/pcm_oss.c:965 snd_pcm_oss_make_ready_locked+0x7d/0x300 sound/core/oss/pcm_oss.c:1186 snd_pcm_oss_write1 sound/core/oss/pcm_oss.c:1404 [inline] snd_pcm_oss_write+0x281/0xf20 sound/core/oss/pcm_oss.c:2794 vfs_write+0x27e/0xb30 fs/read_write.c:684 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888059753e00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 0 bytes inside of allocated 240-byte region [ffff888059753e00, ffff888059753ef0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x59752 head: order:1 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 ffff88813ffa6b40 ffffea0001369900 0000000000000006 raw: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813ffa6b40 ffffea0001369900 0000000000000006 head: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000 head: 00fff00000000001 ffffea000165d481 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 21971, tgid 21970 (syz.3.3979), ts 1340993593432, free_ts 1340989550713 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x234/0x290 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0x24e0/0x2580 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x86/0x3b0 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xe53/0x1820 mm/slub.c:4656 __slab_alloc+0x65/0x100 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] __kmalloc_cache_noprof+0x41e/0x700 mm/slub.c:5771 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] snd_seq_pool_new+0x51/0x1b0 sound/core/seq/seq_memory.c:521 seq_create_client1+0x69/0x6e0 sound/core/seq/seq_clientmgr.c:208 snd_seq_open+0x5f/0x570 sound/core/seq/seq_clientmgr.c:306 chrdev_open+0x4cc/0x5e0 fs/char_dev.c:414 do_dentry_open+0x7ce/0x1420 fs/open.c:962 vfs_open+0x3b/0x340 fs/open.c:1094 do_open fs/namei.c:4628 [inline] path_openat+0x340e/0x3dd0 fs/namei.c:4787 do_filp_open+0x1fa/0x410 fs/namei.c:4814 page last free pid 21980 tgid 21979 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc8/0xd30 mm/page_alloc.c:2943 mm_free_pgd kernel/fork.c:584 [inline] __mmdrop+0xb6/0x750 kernel/fork.c:726 exit_mm+0x169/0x230 kernel/exit.c:581 do_exit+0x627/0x22f0 kernel/exit.c:959 do_group_exit+0x21c/0x2d0 kernel/exit.c:1112 get_signal+0x1285/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x87/0x4e0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2b7/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888059753d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888059753e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888059753e80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc ^ ffff888059753f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888059753f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================