From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D36912D9EF9 for ; Mon, 13 Oct 2025 08:24:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760343852; cv=none; b=eujgKS0nb/P4RCnWFbeHYfQCpqFs0ymtFYeDk3ynLuovTLQBUtjT81f4O0gJmNDfI8nOmgGqSzUKMyRMt7Z6W1E6RC4T1tPv7N7mBb8YUwyQz8vyV835ml9Shp/kYum6a0uPnvnlCYzgVAt5P9ybe0VInL1jaFproDJFkhiTrQE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760343852; c=relaxed/simple; bh=0+aPmQvP5U0qIRoAp1lv+oixENT1rYW2aSGSXxmh4iA=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=HDLHWj1R9taZOyUpNUj4m4HQdoiiN2pQUglfnex76gdFVJJGGIwtlrQfQx0VegBPoJg9NsfQLk+kXiHza/WbFoEDsEV87xvhJWramKjrRl4xzQ4gSgPpLxPvFU45vLH9i0oJ1WNoQAmvVBXB+XpGvBdbWf+JK8jZdn1lyvrsfzA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=l/ga0tEw; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="l/ga0tEw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0DB5CC4CEFE; Mon, 13 Oct 2025 08:24:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1760343852; bh=0+aPmQvP5U0qIRoAp1lv+oixENT1rYW2aSGSXxmh4iA=; h=Subject:To:Cc:From:Date:From; b=l/ga0tEwny/KbUdq0H+FhU3hS4I0YIia47FbyDKEQwOf4mYndZVPzOpTh/fqcgkg8 TiwIzlmF/3t5nF4ileG7F3umrgodPtAa1fckC2vjilTHOMM+VxtVB7yIX9KdNTJ3lG Svo9QRGVS8JtyaugY1zi4wBugrZLz1Ug2dR4t6eY= Subject: FAILED: patch "[PATCH] fs: udf: fix OOB read in lengthAllocDescs handling" failed to apply to 5.10-stable tree To: Sergey.Larshin@kaspersky.com,jack@suse.cz Cc: From: Date: Mon, 13 Oct 2025 10:24:09 +0200 Message-ID: <2025101309-prescribe-imprison-4896@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x 3bd5e45c2ce30e239d596becd5db720f7eb83c99 # git commit -s git send-email --to '' --in-reply-to '2025101309-prescribe-imprison-4896@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 3bd5e45c2ce30e239d596becd5db720f7eb83c99 Mon Sep 17 00:00:00 2001 From: Larshin Sergey Date: Mon, 22 Sep 2025 16:13:58 +0300 Subject: [PATCH] fs: udf: fix OOB read in lengthAllocDescs handling When parsing Allocation Extent Descriptor, lengthAllocDescs comes from on-disk data and must be validated against the block size. Crafted or corrupted images may set lengthAllocDescs so that the total descriptor length (sizeof(allocExtDesc) + lengthAllocDescs) exceeds the buffer, leading udf_update_tag() to call crc_itu_t() on out-of-bounds memory and trigger a KASAN use-after-free read. BUG: KASAN: use-after-free in crc_itu_t+0x1d5/0x2b0 lib/crc-itu-t.c:60 Read of size 1 at addr ffff888041e7d000 by task syz-executor317/5309 CPU: 0 UID: 0 PID: 5309 Comm: syz-executor317 Not tainted 6.12.0-rc4-syzkaller-00261-g850925a8133c #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 crc_itu_t+0x1d5/0x2b0 lib/crc-itu-t.c:60 udf_update_tag+0x70/0x6a0 fs/udf/misc.c:261 udf_write_aext+0x4d8/0x7b0 fs/udf/inode.c:2179 extent_trunc+0x2f7/0x4a0 fs/udf/truncate.c:46 udf_truncate_tail_extent+0x527/0x7e0 fs/udf/truncate.c:106 udf_release_file+0xc1/0x120 fs/udf/file.c:185 __fput+0x23f/0x880 fs/file_table.c:431 task_work_run+0x24f/0x310 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xa2f/0x28e0 kernel/exit.c:939 do_group_exit+0x207/0x2c0 kernel/exit.c:1088 __do_sys_exit_group kernel/exit.c:1099 [inline] __se_sys_exit_group kernel/exit.c:1097 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1097 x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Validate the computed total length against epos->bh->b_size. Found by Linux Verification Center (linuxtesting.org) with Syzkaller. Reported-by: syzbot+8743fca924afed42f93e@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=8743fca924afed42f93e Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Larshin Sergey Link: https://patch.msgid.link/20250922131358.745579-1-Sergey.Larshin@kaspersky.com Signed-off-by: Jan Kara diff --git a/fs/udf/inode.c b/fs/udf/inode.c index f24aa98e6869..a79d73f28aa7 100644 --- a/fs/udf/inode.c +++ b/fs/udf/inode.c @@ -2272,6 +2272,9 @@ int udf_current_aext(struct inode *inode, struct extent_position *epos, if (check_add_overflow(sizeof(struct allocExtDesc), le32_to_cpu(header->lengthAllocDescs), &alen)) return -1; + + if (alen > epos->bh->b_size) + return -1; } switch (iinfo->i_alloc_type) {