From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 793A936B076 for ; Fri, 17 Jul 2026 19:55:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784318120; cv=none; b=AaW9fDrE92cpL1d1aJCdUB4IO8tzkf0wnv3qEIZMRZTKLURWT9zw5c1+LSq1wp3FGHEeY+sgxZmFQ5qUVyHbfzD2oHf2UKsjG3ftTZsZy8/3u/zphV4HHL48C2QuKeOuUPJjf3LHQhMpXLJKLhAL0Z/rXPDWv9WfV45QS9Vo8xk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784318120; c=relaxed/simple; bh=38rB7DNzfVWvpRWRpFiS09jTlq6aoYQ09M47cAqZR9g=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=CNApoahKBsl8CnwEwMKZ+zbnLBf3UYnQGC1owgM0S6/+tq6tvbGnKWzk2W9ex6rcBjY3g5rYvOMnaIoRz3I+h8a5PHLwxba7oEITcss42gdrTaZFPjyyREYz5zrnoOhfr087k3v4AB+CgVnJM74joqTryHV34xRwunKIJnbgkng= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=EOJXU7TU; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="EOJXU7TU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9AEB51F00A3A; Fri, 17 Jul 2026 19:55:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784318119; bh=QYm5iruYgoHs3V8TKuxg1QcPFhu4oyMa+7Vo/jPq72s=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=EOJXU7TUYtZzqeqz1C/e3v7SqBFiO6VPLR5+zsCu2yA5WFJoH/7Iaic5Y0ATpfbkH 64bSAOTXNNiZucTNd1pWBRBSO8Tu7BoxUpQAoHhT7rxHg+kJ7RBTDxtqDsg1tZKXrG z7K4KMlRh3X+Q5tcCAxmQwUxpmDJEYolO2dEGDoJsgWi6Uo4sX2wy91CPteXTQdgAc KL1hsDpydzrE2XupM/25ptRCyGvIK6eC6ia0emKF05mdubGYLp7ZezV6LMM5dUrick fbyXBYCC5pBgSecKuf/s1emIwljwkWJI/tR8laHpVYZbM5U7joEYzcCrYAK1XIJ8wr GPEvojVtBbI0Q== From: Sasha Levin To: stable@vger.kernel.org Cc: Tristan Madani , syzbot+6df204b70bf3261691c5@syzkaller.appspotmail.com, syzbot+e76bf3d19b85350571ac@syzkaller.appspotmail.com, Viacheslav Dubeyko , Sasha Levin Subject: [PATCH 6.18.y 2/2] hfs/hfsplus: fix u32 overflow in check_and_correct_requested_length Date: Fri, 17 Jul 2026 15:55:16 -0400 Message-ID: <20260717195516.2194907-2-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260717195516.2194907-1-sashal@kernel.org> References: <2026071426-subplot-sinister-60df@gregkh> <20260717195516.2194907-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Tristan Madani [ Upstream commit 966cb76fb2857a4242cab6ea2ea17acf818a3da7 ] check_and_correct_requested_length() compares (off + len) against node_size using u32 arithmetic. When the caller passes a large len value (e.g. from an underflowed subtraction in hfs_brec_remove()), off + len can wrap past 2^32 and produce a small result, causing the bounds check to pass when it should fail. For example, with off=14 and len=0xFFFFFFF2 (underflowed from data_off - keyoffset - size in hfs_brec_remove), off + len wraps to 6, which is less than a typical node_size of 512, so the check passes and the subsequent memmove reads ~4GB past the node buffer. Fix this by widening the addition to u64 before comparing against node_size. This prevents the u32 wrap while keeping the logic straightforward. Reported-by: syzbot+6df204b70bf3261691c5@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=6df204b70bf3261691c5 Tested-by: syzbot+6df204b70bf3261691c5@syzkaller.appspotmail.com Reported-by: syzbot+e76bf3d19b85350571ac@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=e76bf3d19b85350571ac Tested-by: syzbot+e76bf3d19b85350571ac@syzkaller.appspotmail.com Fixes: a431930c9bac ("hfs: fix slab-out-of-bounds in hfs_bnode_read()") Cc: stable@vger.kernel.org Signed-off-by: Tristan Madani Reviewed-by: Viacheslav Dubeyko Signed-off-by: Viacheslav Dubeyko Link: https://lore.kernel.org/r/20260505111300.3592757-2-tristmd@gmail.com Signed-off-by: Viacheslav Dubeyko Signed-off-by: Sasha Levin --- fs/hfs/bnode.c | 2 +- fs/hfsplus/hfsplus_fs.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/hfs/bnode.c b/fs/hfs/bnode.c index 13d58c51fc46bf..9571f33b910857 100644 --- a/fs/hfs/bnode.c +++ b/fs/hfs/bnode.c @@ -41,7 +41,7 @@ u32 check_and_correct_requested_length(struct hfs_bnode *node, u32 off, u32 len) node_size = node->tree->node_size; - if ((off + len) > node_size) { + if ((u64)off + len > node_size) { u32 new_len = node_size - off; pr_err("requested length has been corrected: " diff --git a/fs/hfsplus/hfsplus_fs.h b/fs/hfsplus/hfsplus_fs.h index d2cc0f9f3d513d..2da2bd52d200ec 100644 --- a/fs/hfsplus/hfsplus_fs.h +++ b/fs/hfsplus/hfsplus_fs.h @@ -585,7 +585,7 @@ u32 check_and_correct_requested_length(struct hfs_bnode *node, u32 off, u32 len) node_size = node->tree->node_size; - if ((off + len) > node_size) { + if ((u64)off + len > node_size) { u32 new_len = node_size - off; pr_err("requested length has been corrected: " -- 2.53.0