From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f80.google.com (mail-pj1-f80.google.com [209.85.216.80]) (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 BA83A2D6E5A for ; Tue, 19 May 2026 13:01:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.80 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779195695; cv=none; b=HMC87TUYQXoudLnj1yNfTfC9+t5wtFaQTSoy7fDRkJQ4EjQaHz8+t5M5rGYltB4wILgO1F3hA/QX/9nOHoxzhFZFGce8S7j2XtaG7gm6Eq5Uv/o8eDHyb5ZDRS6ChdEj3ycRGRKHsA8lKFYwsICciDavi2B35dWJ+I9fvU8rV/8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779195695; c=relaxed/simple; bh=DqPkcxZ2Iky7o6NSqXBvZSJ5n+PhWbEN8ZbxQIMdLlk=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=RE/4DG3lTYDzz4NwTRDzc3rBEj7qOsvGmoEV4+kf5zih0snyMO7qqUseHmxNWC0LDMhZOEjuvlLFdsPVLNQoR/ynubTRMY50MPtYiruldK+kMd/UPtpjPLBFJqHbKyEpif8b0oXAOrmTxYXMbXP4zQ/IZoPC4GrRn1dVPh3u/Hs= 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=209.85.216.80 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-pj1-f80.google.com with SMTP id 98e67ed59e1d1-368ac44b26dso2957848a91.2 for ; Tue, 19 May 2026 06:01:33 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779195693; x=1779800493; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=3DkQrNtBhC+WBmhuRCOKUoIZJp9AAysSjS7AGbEqjnE=; b=A8Tbs0r0UJ0BPU4GDqYqnzqHab6xZ2hkzwwskmHCSqnkE18Tab8uWL2wwJLAjbYPXj 710Z1Ay4kMNr4MNTQVsd1ZAw6D+tVzc2EyM3DSkb8yk1amSJ6+KvO80JKOtYbnfNJCqg Zl6/LcqEEa4GjVddKzVYu8G1FS1EbjXNihYhbsl1D/548oCeCIY1oIo8Hg4NU9pQb0zQ w/U6Obazmy88/32sGHlaV4+X7JL6gfOuU6LBHckG7h7h2/t9oo046uwttdMwFYLVTmOD O4Fx3wA3mv1JxLPI9EaBSwAm9VtPB95p4mabGECQtaKqKWoPB9UeAseWWHlD1CqvfdWe LPqA== X-Forwarded-Encrypted: i=1; AFNElJ/9I7+JdTJ5tsta8yYJ66Di36fxE27q8Bjvdg1iO/pcJbSQWLODSO5Rf3bCs3EBUEaAdgs=@vger.kernel.org X-Gm-Message-State: AOJu0YwkZbtxiQbmvJbrq0TcN0Dz89wU89tpBwsJqxKH7z68mNICyqe0 FqfvLavNiLroXErIZ6HYx1MTP8yZS//zrswV4RMZj7pgOLNDKoxRjOQzXVyijOIRhRkDE4b4Kw1 jPKryWdzJiBG9JSTSfVaepDb+SUz6KoQNo6jSLdYRKoCxYVD669Bj3tK2huI= Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a17:90b:48c4:b0:35f:d56d:1c45 with SMTP id 98e67ed59e1d1-369519cc92amr18826406a91.12.1779195692869; Tue, 19 May 2026 06:01:32 -0700 (PDT) Date: Tue, 19 May 2026 06:01:32 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a0c5f2c.a00a0220.2c7954.0000.GAE@google.com> Subject: [syzbot] [kvm?] [kvm-x86?] KASAN: use-after-free Read in kvm_xen_shared_info_init From: syzbot To: bp@alien8.de, dave.hansen@linux.intel.com, dwmw2@infradead.org, hpa@zytor.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, mingo@redhat.com, paul@xen.org, pbonzini@redhat.com, seanjc@google.com, syzkaller-bugs@googlegroups.com, tglx@kernel.org, x86@kernel.org Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 4d3a2a466b8d HID: core: Fix size_t specifier in hid_report.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1073cd6a580000 kernel config: https://syzkaller.appspot.com/x/.config?x=d0f0911eedbc130a dashboard link: https://syzkaller.appspot.com/bug?extid=0948c82180d475ad24e2 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/03f143994ada/disk-4d3a2a46.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/de287d829354/vmlinux-4d3a2a46.xz kernel image: https://storage.googleapis.com/syzbot-assets/3467e0106c40/bzImage-4d3a2a46.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+0948c82180d475ad24e2@syzkaller.appspotmail.com ================================================================== BUG: KASAN: use-after-free in kvm_xen_shared_info_init+0x3c6/0x440 arch/x86/kvm/xen.c:90 Read of size 4 at addr ffff8880517e3900 by task syz.2.1046/11260 CPU: 0 UID: 0 PID: 11260 Comm: syz.2.1046 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 kvm_xen_shared_info_init+0x3c6/0x440 arch/x86/kvm/xen.c:90 kvm_xen_hvm_set_attr+0xcef/0x16a0 arch/x86/kvm/xen.c:806 kvm_arch_vm_ioctl+0x2a0/0x18d0 arch/x86/kvm/x86.c:7528 kvm_vm_ioctl+0x1564/0x4050 virt/kvm/kvm_main.c:5380 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 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: 0033:0x7f62be79ce59 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:00007f62bf733028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f62bea15fa0 RCX: 00007f62be79ce59 RDX: 0000000000000004 RSI: 000000004048aec9 RDI: 0000000000000003 RBP: 00007f62be832d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f62bea16038 R14: 00007f62bea15fa0 R15: 00007ffcbacd7668 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x4 pfn:0x517e3 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea0001595b88 ffff8880b84412f0 0000000000000000 raw: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Movable, gfp_mask 0x140cca(GFP_HIGHUSER_MOVABLE|__GFP_COMP), pid 11260, tgid 11259 (syz.2.1046), ts 375671463264, free_ts 375831741570 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_pages_mpol+0x1fb/0x540 mm/mempolicy.c:2490 folio_alloc_mpol_noprof+0x36/0x260 mm/mempolicy.c:2509 vma_alloc_folio_noprof+0xed/0x1d0 mm/mempolicy.c:2544 folio_prealloc mm/memory.c:1193 [inline] wp_page_copy mm/memory.c:3859 [inline] do_wp_page+0x1ee1/0x4350 mm/memory.c:4320 handle_pte_fault mm/memory.c:6427 [inline] __handle_mm_fault+0x1ab6/0x2a00 mm/memory.c:6549 handle_mm_fault+0x36d/0xa20 mm/memory.c:6718 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x1178/0x32a0 mm/gup.c:1428 __get_user_pages_locked mm/gup.c:1692 [inline] get_user_pages_unlocked+0x1cb/0x7d0 mm/gup.c:2681 hva_to_pfn_slow virt/kvm/kvm_main.c:2903 [inline] hva_to_pfn+0x871/0xd60 virt/kvm/kvm_main.c:2999 hva_to_pfn_retry virt/kvm/pfncache.c:209 [inline] __kvm_gpc_refresh+0xcea/0x22c0 virt/kvm/pfncache.c:330 __kvm_gpc_activate+0x2ab/0x490 virt/kvm/pfncache.c:424 kvm_gpc_activate_hva+0x73/0xa0 virt/kvm/pfncache.c:444 kvm_xen_hvm_set_attr+0x395/0x16a0 arch/x86/kvm/xen.c:798 page last free pid 11260 tgid 11259 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 __folio_put+0x3b4/0x5f0 mm/swap.c:112 folio_put include/linux/mm.h:2090 [inline] put_page include/linux/mm.h:2159 [inline] kvm_release_page_clean virt/kvm/kvm_main.c:2813 [inline] kvm_release_page_clean+0x1dc/0x250 virt/kvm/kvm_main.c:2807 hva_to_pfn_retry virt/kvm/pfncache.c:246 [inline] __kvm_gpc_refresh+0x195d/0x22c0 virt/kvm/pfncache.c:330 __kvm_gpc_activate+0x2ab/0x490 virt/kvm/pfncache.c:424 kvm_gpc_activate_hva+0x73/0xa0 virt/kvm/pfncache.c:444 kvm_xen_hvm_set_attr+0x395/0x16a0 arch/x86/kvm/xen.c:798 kvm_arch_vm_ioctl+0x2a0/0x18d0 arch/x86/kvm/x86.c:7528 kvm_vm_ioctl+0x1564/0x4050 virt/kvm/kvm_main.c:5380 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 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 Memory state around the buggy address: ffff8880517e3800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880517e3880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8880517e3900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8880517e3980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880517e3a00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup