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 EBDCC1C8603 for ; Sat, 18 Jul 2026 00:51:18 +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=1784335880; cv=none; b=PafFebY6vArfJ+Gc1PDSyM8ZRPwvVKbT9vOBgcx+xC2vAFNLPHldV4Co+xqNDhmKGhBqlttWZEzD+mWFwudTIvnkVGH98uUJKuDaFuBFBo25GNTg10FOxIyFjb8Jiiw4IFFFCC1jkNRaYcyySioKcRwtih/Onk6mGu999zEjkSE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784335880; c=relaxed/simple; bh=uiv+m0orN6qKT2D2RZEJtganZlr3DMSPD08Wb4H7KxQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=qI+TpDWuqSduk6yN5EeLCKDpQrv+EQFqXIYg7U+tXe7eaC4c45emGwKcJQmGN99I9RFb/eATDXYD50KrNScJDNHC53kJbLk0eBb+tz0vnEhmW8ol5LiNi6R6/WdJSuwMgBQkGyc417IgowTEnexAnqtUfKbavwfDYQitApVz9Qg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=PRqRNQMe; 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="PRqRNQMe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2970E1F00A3A; Sat, 18 Jul 2026 00:51:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784335878; bh=OqJl/no25bH7Pk2EjnA6/yCe6VyrEXX+l2UtfJgdOUg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=PRqRNQMeWKj2w6El5g8T/fqqThbZCjhb7kv8YdWGbKU2vYnyuZKruEZdJIk/bLvU+ YbbUIeIT2hg1qkMnLzucmLWtilDWRHH79M6i1y8JzPe004EzzED49+uvN/vm8nSvuH WIZqNIOwiC6T+7vZHfN0Va/oVbVlc9oNnOLeXllwwxa+kkDPp+AHtNIjz5rIDrNi9q Up+o8gxkyCMfNzrbEwITjMTOXmaU3dlZNcbtVkIYOkLa2PxRa+mX31E+uP3BcYki6b 8Z81ro1r5WtPlX7aYfiWCc+rRxKbR4qhUsq+BAlilD+GShQLLTcjNCkaQ5hqvlX4bx Bh+9STRnD5xLw== 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 6.12.y 2/2] hfs/hfsplus: fix u32 overflow in check_and_correct_requested_length Date: Fri, 17 Jul 2026 20:51:15 -0400 Message-ID: <20260718005115.2484456-2-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260718005115.2484456-1-sashal@kernel.org> References: <2026071426-smirk-video-c05b@gregkh> <20260718005115.2484456-1-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 e239bcef8b1f49..2de2790315c87d 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 12e55e8ed94fe2..11cef30803d5ad 100644 --- a/fs/hfsplus/hfsplus_fs.h +++ b/fs/hfsplus/hfsplus_fs.h @@ -614,7 +614,7 @@ 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