From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f77.google.com (mail-oo1-f77.google.com [209.85.161.77]) (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 8C9C42FFF90 for ; Sun, 9 Aug 2026 21:51:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.77 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786312293; cv=none; b=M9c7MCEZ/9ScD/PrpV7pjlwSZQL7VFH1O6/maxBrLJ7fnjGyrjohPzxe3gavpCltGp1zX6ht2eWauWgrT+OasbxDhL9zweJXwkTWI2i/Y2c3q3ptFJYYVBdXE/Q3otTer0Zw1/KryzUkydgztGCdv0G61O/r4psz9ijEer41z+g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786312293; c=relaxed/simple; bh=WY9FAFiTekcTQzamWFn7NLA8/c0tUAy11t7oHE+rePY=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=T2BVHTNzT4YL/uOclSYeVYmDPX5mrphxU09msJMuDwOlwPiMi3tqUtce7DuE6oUQVeeOUfPpYhj9bd0j4HzdelntnAaHrqlu+oIQ/SOrnCYBMKN5eCbbiBjayZVuaO4C4Xkhbp33ktezNUzr3iTNG6ytd5RzhgW/Oq/B6a8nJys= 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=209.85.161.77 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-oo1-f77.google.com with SMTP id 006d021491bc7-6aaefd6909fso498608eaf.2 for ; Sun, 09 Aug 2026 14:51:31 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1786312290; x=1786917090; h=content-type:to:from:subject:message-id:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=V1ZlWHjVY7ndYW1ZsOFi+iZRZGVj81O6tO9Dw18q/yM=; b=JGukh8IAm7rID4HfW5udZNvRpG62cC3QYO73zaDTLyD/0zCzrb1wTaM4DzhTYGFNiK gsU5W0/xFbAOQKqfG4375oKkuhxCPRlZh1gjdi7BNoq4kRNUI2rcZoeVMpN63cyNMw4M WCqs+ZbdffWpSGis/De03JrgZ/nKzmUPMwN+chCv+WZIwPqBlFYTyXve8g319tQ33gAO pM3LtwlFMsRT7cue3j2n4Rh8OnvJWfnzh3TIl7OJO3sZGQitcg24rjn7RgM9e50i0Sip Aw6R3mb26iLmpipb+sYCdkh2LK1CXy9foWjxuFhFBY/kD3x6xdLAt06EbhIERKSb9LHU Ilig== X-Gm-Message-State: AOJu0YwhE+ZDPvpOl1NoSKwZYUCvQrcXdY/CL/+dr/LCKMGLEX+b0QwI ZZ9CvLLKCQQWHQ+AdVWeig3LuPSShXM8IRJsL2e2wjNmHWx4LNVO+RaKZ6f8a4iLOmLfUoylY8A 0dFr7VHm0DLukngW8LRnWAbSGSwWbZxrzVBUTpnS/Qr7BgkUGEtcjqCizAi+2Lw== Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:208c:b0:69e:3e6b:c07 with SMTP id 006d021491bc7-6ae96c1edb3mr19908278eaf.5.1786312290501; Sun, 09 Aug 2026 14:51:30 -0700 (PDT) Date: Sun, 09 Aug 2026 14:51:30 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a78f662.b50370da.49fe0.0045.GAE@google.com> Subject: [syzbot] [trace?] KASAN: use-after-free Read in ignore_event From: syzbot To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, mathieu.desnoyers@efficios.com, mhiramat@kernel.org, rostedt@goodmis.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 3708dd948844 Merge tag 'pm-7.2-rc6' of git://git.kernel.or.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=17557a49580000 kernel config: https://syzkaller.appspot.com/x/.config?x=b7079b368dcec295 dashboard link: https://syzkaller.appspot.com/bug?extid=0b5074bf48547b3a63ac 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/3cbcba767cb8/disk-3708dd94.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/37b77da165c5/vmlinux-3708dd94.xz kernel image: https://storage.googleapis.com/syzbot-assets/0f4930dc3972/bzImage-3708dd94.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+0b5074bf48547b3a63ac@syzkaller.appspotmail.com ================================================================== BUG: KASAN: use-after-free in ignore_event+0x83e/0xaa0 kernel/trace/trace.c:2526 Read of size 2 at addr ffff88804705a1ac by task syz.6.1383/11771 CPU: 0 UID: 0 PID: 11771 Comm: syz.6.1383 Tainted: G S syzkaller #0 PREEMPT(full) Tainted: [S]=CPU_OUT_OF_SPEC Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 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/0x1c0 mm/kasan/report.c:595 ignore_event+0x83e/0xaa0 kernel/trace/trace.c:2526 trace_event_printf+0xb5/0x160 kernel/trace/trace_output.c:356 trace_raw_output_sys_enter+0x4c/0x60 include/trace/events/syscalls.h:18 print_trace_fmt kernel/trace/trace.c:3071 [inline] print_trace_line+0x97d/0x1790 kernel/trace/trace.c:3237 tracing_read_pipe+0x586/0xd60 kernel/trace/trace.c:5444 vfs_read+0x1e4/0xb40 fs/read_write.c:572 ksys_read+0x12a/0x250 fs/read_write.c:716 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f48cdd9e019 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:00007f48cebb5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f48ce025fa0 RCX: 00007f48cdd9e019 RDX: 0000000000002000 RSI: 0000200000001000 RDI: 0000000000000003 RBP: 00007f48cde3500c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f48ce026038 R14: 00007f48ce025fa0 R15: 00007ffe7508fde8 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4705a flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea00009a6048 ffffea00007bac08 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0x44dc0(GFP_KERNEL|__GFP_ZERO|__GFP_RETRY_MAYFAIL|__GFP_COMP), pid 9023, tgid 9022 (syz.6.770), ts 304966657874, free_ts 587151444439 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304 __alloc_pages_noprof+0xb/0x110 mm/page_alloc.c:5338 __alloc_pages_node_noprof include/linux/gfp.h:291 [inline] alloc_pages_node_noprof include/linux/gfp.h:318 [inline] alloc_cpu_data+0x60/0x160 kernel/trace/ring_buffer.c:427 __rb_allocate_pages+0xbd5/0x10a0 kernel/trace/ring_buffer.c:2436 ring_buffer_resize+0x6df/0x1e80 kernel/trace/ring_buffer.c:3270 __tracing_resize_ring_buffer.part.0+0x52/0x1f0 kernel/trace/trace.c:4738 __tracing_resize_ring_buffer kernel/trace/trace.c:4732 [inline] tracing_update_buffers+0xd4/0xf0 kernel/trace/trace.c:4977 event_enable_write+0x23f/0x340 kernel/trace/trace_events.c:1926 vfs_write+0x2aa/0x1050 fs/read_write.c:685 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 11775 tgid 11774 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950 free_buffer_page kernel/trace/ring_buffer.c:398 [inline] ring_buffer_subbuf_order_set+0x12d5/0x18a0 kernel/trace/ring_buffer.c:7439 buffer_subbuf_size_write+0x182/0x280 kernel/trace/trace.c:8221 vfs_write+0x2aa/0x1050 fs/read_write.c:685 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88804705a080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88804705a100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88804705a180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88804705a200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88804705a280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== --- This report is generated by a bot. 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