================================================================== BUG: KASAN: slab-out-of-bounds in copy_to_urb+0x21f/0x410 sound/usb/pcm.c:1393 Write of size 264 at addr ffff8880729d6400 by task syz.0.17/4436 CPU: 0 PID: 4436 Comm: syz.0.17 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x235/0x290 mm/kasan/generic.c:189 memcpy+0x3c/0x60 mm/kasan/shadow.c:66 copy_to_urb+0x21f/0x410 sound/usb/pcm.c:1393 prepare_playback_urb+0x910/0x1440 sound/usb/pcm.c:1521 snd_usb_endpoint_start+0x4a6/0x12e0 sound/usb/endpoint.c:1620 start_endpoints+0xa1/0x270 sound/usb/pcm.c:273 snd_usb_substream_playback_trigger+0x3eb/0x7d0 sound/usb/pcm.c:1625 snd_pcm_action_single sound/core/pcm_native.c:1293 [inline] snd_pcm_action+0xda/0x230 sound/core/pcm_native.c:1376 __snd_pcm_lib_xfer+0x17ba/0x1c90 sound/core/pcm_lib.c:2310 snd_pcm_oss_write3+0x1b8/0x310 sound/core/oss/pcm_oss.c:1252 snd_pcm_plug_write_transfer+0x2ba/0x4b0 sound/core/oss/pcm_plugin.c:630 snd_pcm_oss_write2+0x1a5/0x410 sound/core/oss/pcm_oss.c:1384 snd_pcm_oss_write1 sound/core/oss/pcm_oss.c:1450 [inline] snd_pcm_oss_write+0x6a7/0xaf0 sound/core/oss/pcm_oss.c:2810 vfs_write+0x2e6/0xa30 fs/read_write.c:582 ksys_write+0x14c/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fcaac59aeb9 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:00007ffcc59f6fd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fcaac815fa0 RCX: 00007fcaac59aeb9 RDX: 00000000000005ce RSI: 0000200000000640 RDI: 0000000000000004 RBP: 00007fcaac608c1f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fcaac815fac R14: 00007fcaac815fa0 R15: 00007fcaac815fa0 Allocated by task 4436: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc+0xb0/0x240 mm/slab_common.c:949 data_ep_set_params sound/usb/endpoint.c:1259 [inline] snd_usb_endpoint_set_params+0x17f5/0x2f00 sound/usb/endpoint.c:1397 snd_usb_hw_params+0x1239/0x19d0 sound/usb/pcm.c:569 snd_pcm_hw_params+0x8a2/0x1ce0 sound/core/pcm_native.c:779 snd_pcm_oss_change_params_locked+0x206b/0x3c50 sound/core/oss/pcm_oss.c:976 snd_pcm_oss_make_ready_locked sound/core/oss/pcm_oss.c:1197 [inline] snd_pcm_oss_write1 sound/core/oss/pcm_oss.c:1415 [inline] snd_pcm_oss_write+0x277/0xaf0 sound/core/oss/pcm_oss.c:2810 vfs_write+0x2e6/0xa30 fs/read_write.c:582 ksys_write+0x14c/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff8880729d6400 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 0 bytes inside of 192-byte region [ffff8880729d6400, ffff8880729d64c0) The buggy address belongs to the physical page: page:ffffea0001ca7580 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x729d6 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 0000000000000000 dead000000000122 ffff888017441a00 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 24, tgid 24 (kdevtmpfs), ts 85378607699, free_ts 85342998293 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4328 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5614 __alloc_pages_node include/linux/gfp.h:237 [inline] alloc_slab_page+0x4f/0x160 mm/slub.c:1801 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc_node+0xa0/0x240 mm/slab_common.c:943 kmalloc_array_node include/linux/slab.h:676 [inline] kcalloc_node include/linux/slab.h:681 [inline] memcg_alloc_slab_cgroups+0x83/0x120 mm/memcontrol.c:2889 account_slab mm/slab.h:635 [inline] allocate_slab mm/slub.c:1962 [inline] new_slab+0xc3/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc_lru+0x1ae/0x2e0 mm/slub.c:3390 alloc_inode_sb include/linux/fs.h:3245 [inline] shmem_alloc_inode+0x24/0x40 mm/shmem.c:3898 alloc_inode fs/inode.c:261 [inline] new_inode_pseudo+0x5f/0x1c0 fs/inode.c:1063 new_inode+0x25/0x1c0 fs/inode.c:1091 shmem_get_inode+0x347/0xbf0 mm/shmem.c:2354 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1459 [inline] free_pcp_prepare mm/page_alloc.c:1509 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479 free_slab mm/slub.c:2036 [inline] discard_slab mm/slub.c:2042 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2591 put_cpu_partial+0x17c/0x250 mm/slub.c:2667 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] __kmem_cache_alloc_node+0x140/0x260 mm/slub.c:3398 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] nsim_fib4_rt_create drivers/net/netdevsim/fib.c:280 [inline] nsim_fib4_rt_insert drivers/net/netdevsim/fib.c:426 [inline] nsim_fib4_event drivers/net/netdevsim/fib.c:464 [inline] nsim_fib_event drivers/net/netdevsim/fib.c:884 [inline] nsim_fib_event_work+0x891/0x3450 drivers/net/netdevsim/fib.c:1494 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 process_scheduled_works kernel/workqueue.c:2355 [inline] worker_thread+0xd27/0x1270 kernel/workqueue.c:2441 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff8880729d6380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880729d6400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880729d6480: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880729d6500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880729d6580: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================