From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f207.google.com (mail-oi1-f207.google.com [209.85.167.207]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 426B5403E84 for ; Fri, 22 May 2026 14:05:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.207 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779458750; cv=none; b=nWMNQzWo4MGUCdHyzILEHCapm2bPlJjMkLwmkn2v53rk9a0WWEhXcTf/WGxdqj23OkihFrmWCmmotZZrtdL9nR11VU9J5dCzTUIVNpxqBZRa73GL0dAGdNpQLqG37U+XKLww9oekUKoUolVDVoMuYeg2uGkCWAbvKdwgWQH5ZCE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779458750; c=relaxed/simple; bh=53WAMty960onyx+uULkWfvkJXjJxSe29ATNZ+Id6eVY=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=YwRZBZHG4QQr36eGZJsxKZO7Kt7o2ZS4An5PNtL/J0BP0v9vemOgaEdWExX+qpcjzoNJWRRIsXlBgHmDsh28lchklS6k0oJ9O/WNcsyUaaNsrKBIzD7k2e9hYIYAlH/WCc/eP0DRu1h/AzgSoQ+Gdy3i5PqWN9GFNryswODLwYc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.167.207 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oi1-f207.google.com with SMTP id 5614622812f47-4855062d218so729381b6e.0 for ; Fri, 22 May 2026 07:05:45 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779458743; x=1780063543; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=+ZIiWkn0A9nMZoxqIl5sEKCHY941oTcWCUaSE0Q1Czs=; b=CuaCBtaBaCPdq/gpuylMAA8zQmvoz/2o3RdklV5u5eojVcT3WEG5iIBxZp3wUeAWRQ uGlBwsoAZWWhm/2BumgZ8eykuBV/Fw+uKMLs92xJVM0Ly/xLrD8xQ0ZpvBKM3oY4h1TE zZf26RflirQduj8sPwNOuXepAWwfKXkgDJZONzye98eilTCCN0rj+TINqAqjMcocgLOK 50QDE+DMnHrCraOG7KXt9X3xCQBKdONsoPaoMeAFfHJlj+KNA+MHl0yBwDE0WjCIJkWc MlYVRgqRz1vpV78/ydUXegCORCkU9baaqt+gIchUBcVQzxFlsOXD7XPHb9fu/8m5uWst nNrw== X-Gm-Message-State: AOJu0YwPznaBQ23+6C2/dZBM4HVUQVsxVhtg5FB7O98vwORAqp0+8nYo qtF15QW/pxpu28S2BUW9hbyt9Bsb0vr62N/GtLIm8Z7Z3AYDswwAsaGOZv7HivXJQJzd8HP0nhA M2cjGE0eCVtYvvbbOhKbTNlKRJR2PPWACMT8qvtqOEgs0syyVA8Vm8fcqWLj17g== Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:4fe6:b0:479:ffcf:52dc with SMTP id 5614622812f47-4854a3af8f8mr2153338b6e.44.1779458743571; Fri, 22 May 2026 07:05:43 -0700 (PDT) Date: Fri, 22 May 2026 07:05:43 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a1062b7.170a0220.35b2b7.0003.GAE@google.com> Subject: [syzbot] [sound?] KASAN: slab-use-after-free Read in snd_pcm_oss_look_for_setup (2) From: syzbot To: linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, perex@perex.cz, syzkaller-bugs@googlegroups.com, tiwai@suse.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 6916d5703ddf Merge tag 'drm-fixes-2026-05-16' of https://g.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=15012536580000 kernel config: https://syzkaller.appspot.com/x/.config?x=d0f0911eedbc130a dashboard link: https://syzkaller.appspot.com/bug?extid=8e498074a794999eb41c compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/1efefe7c73e1/disk-6916d570.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/1dcf16f12a0f/vmlinux-6916d570.xz kernel image: https://storage.googleapis.com/syzbot-assets/7bc2e1f3e5cd/bzImage-6916d570.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+8e498074a794999eb41c@syzkaller.appspotmail.com ================================================================== BUG: KASAN: slab-use-after-free in snd_pcm_oss_look_for_setup+0x2d3/0x370 sound/core/oss/pcm_oss.c:2355 Read of size 8 at addr ffff888022f56d00 by task syz.1.988/10837 CPU: 0 UID: 0 PID: 10837 Comm: syz.1.988 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1d0 mm/kasan/report.c:595 snd_pcm_oss_look_for_setup+0x2d3/0x370 sound/core/oss/pcm_oss.c:2355 snd_pcm_oss_open+0xddc/0x1390 sound/core/oss/pcm_oss.c:2521 soundcore_open+0x2e3/0x5a0 sound/sound_core.c:594 chrdev_open+0x234/0x6a0 fs/char_dev.c:411 do_dentry_open+0x6d8/0x1660 fs/open.c:947 vfs_open+0x82/0x3f0 fs/open.c:1079 do_open fs/namei.c:4699 [inline] path_openat+0x208c/0x31a0 fs/namei.c:4858 do_file_open+0x20e/0x430 fs/namei.c:4887 do_sys_openat2+0x10d/0x1e0 fs/open.c:1364 do_sys_open fs/open.c:1370 [inline] __do_sys_openat fs/open.c:1386 [inline] __se_sys_openat fs/open.c:1381 [inline] __x64_sys_openat+0x12d/0x210 fs/open.c:1381 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fda1919ce59 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:00007fda1a0fa028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fda19416090 RCX: 00007fda1919ce59 RDX: 0000000000020342 RSI: 00002000000001c0 RDI: ffffffffffffff9c RBP: 00007fda19232d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fda19416128 R14: 00007fda19416090 R15: 00007ffdc6f4a5c8 Allocated by task 10831: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kmalloc_noprof include/linux/slab.h:950 [inline] snd_pcm_oss_proc_write+0x736/0x9a0 sound/core/oss/pcm_oss.c:3058 snd_info_text_entry_release+0xfb/0x260 sound/core/info.c:386 close_pdeo.part.0+0xdf/0x2e0 fs/proc/inode.c:242 close_pdeo fs/proc/inode.c:540 [inline] proc_reg_release+0x2df/0x350 fs/proc/inode.c:546 __fput+0x3ff/0xb50 fs/file_table.c:510 task_work_run+0x150/0x240 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+0x107/0x4f0 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:318 [inline] do_syscall_64+0x6f2/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 10831: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/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:6250 [inline] kfree+0x223/0x6c0 mm/slub.c:6565 snd_pcm_oss_proc_write+0x7b1/0x9a0 sound/core/oss/pcm_oss.c:3072 snd_info_text_entry_release+0xfb/0x260 sound/core/info.c:386 close_pdeo.part.0+0xdf/0x2e0 fs/proc/inode.c:242 close_pdeo fs/proc/inode.c:540 [inline] proc_reg_release+0x2df/0x350 fs/proc/inode.c:546 __fput+0x3ff/0xb50 fs/file_table.c:510 task_work_run+0x150/0x240 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+0x107/0x4f0 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:318 [inline] do_syscall_64+0x6f2/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888022f56d00 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of freed 32-byte region [ffff888022f56d00, ffff888022f56d20) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888022f56240 pfn:0x22f56 flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000200 ffff88813fe2f780 ffffea0000d47510 ffffea0000ca7a10 raw: ffff888022f56240 000000080040003f 00000000f5000000 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 0xd2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5387, tgid 5387 (getty), ts 194081637728, free_ts 194058318447 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x153/0x170 mm/page_alloc.c:1858 prep_new_page mm/page_alloc.c:1866 [inline] get_page_from_freelist+0x11a6/0x33b0 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x27c/0x2bc0 mm/page_alloc.c:5226 alloc_slab_page mm/slub.c:3278 [inline] allocate_slab mm/slub.c:3467 [inline] new_slab+0xa6/0x6c0 mm/slub.c:3525 refill_objects+0x277/0x420 mm/slub.c:7271 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x375/0x650 mm/slub.c:4651 alloc_from_pcs mm/slub.c:4749 [inline] slab_alloc_node mm/slub.c:4883 [inline] __kmalloc_cache_noprof+0x493/0x6f0 mm/slub.c:5414 kmalloc_noprof include/linux/slab.h:950 [inline] slab_free_hook mm/slub.c:2641 [inline] slab_free mm/slub.c:6250 [inline] kmem_cache_free+0x41e/0x6c0 mm/slub.c:6377 tear_down_vmas+0x2a5/0x600 mm/mmap.c:1262 exit_mmap+0x469/0xa10 mm/mmap.c:1320 __mmput+0x12a/0x410 kernel/fork.c:1178 mmput+0x67/0x80 kernel/fork.c:1201 exit_mm kernel/exit.c:582 [inline] do_exit+0x8b2/0x2af0 kernel/exit.c:964 do_group_exit+0xd5/0x2a0 kernel/exit.c:1119 __do_sys_exit_group kernel/exit.c:1130 [inline] __se_sys_exit_group kernel/exit.c:1128 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1128 x64_sys_call+0x102c/0x1530 arch/x86/include/generated/asm/syscalls_64.h:232 page last free pid 15 tgid 15 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1402 [inline] __free_frozen_pages+0x747/0x1040 mm/page_alloc.c:2943 __pagetable_free include/linux/mm.h:3661 [inline] pagetable_free include/linux/mm.h:3685 [inline] pagetable_dtor_free include/linux/mm.h:3784 [inline] __tlb_remove_table include/asm-generic/tlb.h:221 [inline] __tlb_remove_table_free mm/mmu_gather.c:228 [inline] tlb_remove_table_rcu+0x2cf/0x380 mm/mmu_gather.c:291 rcu_do_batch kernel/rcu/tree.c:2617 [inline] rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2869 handle_softirqs+0x1ea/0xa00 kernel/softirq.c:622 run_ksoftirqd kernel/softirq.c:1076 [inline] run_ksoftirqd+0x38/0x60 kernel/softirq.c:1068 smpboot_thread_fn+0x3d3/0xaa0 kernel/smpboot.c:160 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff888022f56c00: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ffff888022f56c80: 00 00 00 fc fc fc fc fc fa fb fb fb fc fc fc fc >ffff888022f56d00: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ^ ffff888022f56d80: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ffff888022f56e00: 00 00 00 fc fc fc fc fc fa fb fb fb fc fc fc fc ================================================================== --- This report is generated by a bot. 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