================================================================== BUG: KASAN: use-after-free in __snd_rawmidi_transmit_peek sound/core/rawmidi.c:1286 [inline] BUG: KASAN: use-after-free in snd_rawmidi_transmit+0x39a/0x410 sound/core/rawmidi.c:1411 Read of size 1 at addr ffff88805c578069 by task ksoftirqd/1/20 CPU: 1 PID: 20 Comm: ksoftirqd/1 Not tainted 5.15.164-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 print_address_description+0x63/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0x16b/0x1c0 mm/kasan/report.c:451 __snd_rawmidi_transmit_peek sound/core/rawmidi.c:1286 [inline] snd_rawmidi_transmit+0x39a/0x410 sound/core/rawmidi.c:1411 snd_usbmidi_standard_output+0x1eb/0xf20 sound/usb/midi.c:650 snd_usbmidi_do_output+0x206/0x520 sound/usb/midi.c:311 snd_usbmidi_error_timer+0x2a3/0x580 sound/usb/midi.c:362 call_timer_fn+0x16d/0x560 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1496 [inline] __run_timers+0x67c/0x890 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558 run_ksoftirqd+0xc6/0x120 kernel/softirq.c:925 smpboot_thread_fn+0x51b/0x9d0 kernel/smpboot.c:164 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Allocated by task 8335: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc+0xba/0xf0 mm/kasan/common.c:513 kasan_kmalloc include/linux/kasan.h:264 [inline] __kmalloc_node+0x199/0x390 mm/slub.c:4455 kmalloc_node include/linux/slab.h:614 [inline] kvmalloc_node+0x80/0x140 mm/util.c:619 kvmalloc include/linux/mm.h:805 [inline] kvzalloc include/linux/mm.h:813 [inline] snd_rawmidi_runtime_create sound/core/rawmidi.c:162 [inline] open_substream+0x2a4/0x6d0 sound/core/rawmidi.c:306 rawmidi_open_priv+0xc2/0x680 sound/core/rawmidi.c:357 snd_rawmidi_kernel_open+0x1b3/0x240 sound/core/rawmidi.c:392 midisynth_use+0xe7/0x2a0 sound/core/seq/seq_midi.c:221 subscribe_port sound/core/seq/seq_ports.c:412 [inline] check_and_subscribe_port+0x604/0xab0 sound/core/seq/seq_ports.c:495 snd_seq_port_connect+0x284/0x480 sound/core/seq/seq_ports.c:581 snd_seq_ioctl_subscribe_port+0x31a/0x780 sound/core/seq/seq_clientmgr.c:1490 snd_seq_oss_midi_open+0x425/0x9c0 sound/core/seq/oss/seq_oss_midi.c:365 snd_seq_oss_synth_setup_midi+0x114/0x500 sound/core/seq/oss/seq_oss_synth.c:269 snd_seq_oss_open+0x942/0x1010 sound/core/seq/oss/seq_oss_init.c:261 odev_open+0x5f/0x90 sound/core/seq/oss/seq_oss.c:128 chrdev_open+0x54a/0x630 fs/char_dev.c:414 do_dentry_open+0x807/0xfb0 fs/open.c:826 do_open fs/namei.c:3608 [inline] path_openat+0x2705/0x2f20 fs/namei.c:3742 do_filp_open+0x21c/0x460 fs/namei.c:3769 do_sys_openat2+0x13b/0x4f0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1280 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 8335: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x80 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0xf1/0x270 mm/slub.c:4559 snd_rawmidi_runtime_free sound/core/rawmidi.c:176 [inline] close_substream+0x390/0x600 sound/core/rawmidi.c:528 rawmidi_release_priv+0xf1/0x180 sound/core/rawmidi.c:547 snd_rawmidi_kernel_release+0x42/0xa0 sound/core/rawmidi.c:564 unsubscribe_port sound/core/seq/seq_ports.c:437 [inline] __delete_and_unsubscribe_port+0x2c5/0x470 sound/core/seq/seq_ports.c:537 snd_seq_port_disconnect+0x4ab/0x5d0 sound/core/seq/seq_ports.c:616 snd_seq_ioctl_unsubscribe_port+0x31a/0x780 sound/core/seq/seq_clientmgr.c:1535 snd_seq_oss_midi_close+0x348/0x760 sound/core/seq/oss/seq_oss_midi.c:413 snd_seq_oss_synth_reset+0x3c2/0xa20 sound/core/seq/oss/seq_oss_synth.c:406 snd_seq_oss_reset+0x57/0x240 sound/core/seq/oss/seq_oss_init.c:436 snd_seq_oss_release+0xea/0x300 sound/core/seq/oss/seq_oss_init.c:413 odev_release+0x52/0x70 sound/core/seq/oss/seq_oss.c:144 __fput+0x3fe/0x8e0 fs/file_table.c:280 task_work_run+0x129/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88805c578000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 105 bytes inside of 4096-byte region [ffff88805c578000, ffff88805c579000) The buggy address belongs to the page: page:ffffea0001715e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5c578 head:ffffea0001715e00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888011c42140 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 8335, ts 354223019253, free_ts 350281513465 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159 __alloc_pages+0x272/0x700 mm/page_alloc.c:5423 alloc_slab_page mm/slub.c:1775 [inline] allocate_slab mm/slub.c:1912 [inline] new_slab+0xbb/0x4b0 mm/slub.c:1975 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008 __slab_alloc mm/slub.c:3095 [inline] slab_alloc_node mm/slub.c:3186 [inline] __kmalloc_node+0x1fa/0x390 mm/slub.c:4451 kmalloc_node include/linux/slab.h:614 [inline] kvmalloc_node+0x80/0x140 mm/util.c:619 kvmalloc include/linux/mm.h:805 [inline] kvzalloc include/linux/mm.h:813 [inline] snd_rawmidi_runtime_create sound/core/rawmidi.c:162 [inline] open_substream+0x2a4/0x6d0 sound/core/rawmidi.c:306 rawmidi_open_priv+0xc2/0x680 sound/core/rawmidi.c:357 snd_rawmidi_kernel_open+0x1b3/0x240 sound/core/rawmidi.c:392 midisynth_use+0xe7/0x2a0 sound/core/seq/seq_midi.c:221 subscribe_port sound/core/seq/seq_ports.c:412 [inline] check_and_subscribe_port+0x604/0xab0 sound/core/seq/seq_ports.c:495 snd_seq_port_connect+0x284/0x480 sound/core/seq/seq_ports.c:581 snd_seq_ioctl_subscribe_port+0x31a/0x780 sound/core/seq/seq_clientmgr.c:1490 snd_seq_oss_midi_open+0x425/0x9c0 sound/core/seq/oss/seq_oss_midi.c:365 snd_seq_oss_synth_setup_midi+0x114/0x500 sound/core/seq/oss/seq_oss_synth.c:269 snd_seq_oss_open+0x942/0x1010 sound/core/seq/oss/seq_oss_init.c:261 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317 free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396 __vunmap+0x8d4/0xa20 mm/vmalloc.c:2621 kcov_put kernel/kcov.c:408 [inline] kcov_close+0x27/0x50 kernel/kcov.c:510 __fput+0x3fe/0x8e0 fs/file_table.c:280 task_work_run+0x129/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0x6a3/0x2480 kernel/exit.c:874 do_group_exit+0x144/0x310 kernel/exit.c:996 get_signal+0xc66/0x14e0 kernel/signal.c:2889 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Memory state around the buggy address: ffff88805c577f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805c577f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805c578000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805c578080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805c578100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb 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