From: Tobias Stoeckmann <tobias@stoeckmann.org>
Date: Mon, 6 Jul 2026 15:38:52 +0000 (+0200)
Subject: cab: Fix Kraft's inequality check
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=898b63c19beedb8db851659d6a0445a090245994;p=thirdparty%2Flibarchive.git

cab: Fix Kraft's inequality check

We really have to check if Kraft's inequality is 1 (in our case it's
0x10000) or 0 for an empty tree. Anything else is an error.

Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>
---

diff --git a/libarchive/archive_read_support_format_cab.c b/libarchive/archive_read_support_format_cab.c
index 9a37fb242..ad7e848be 100644
--- a/libarchive/archive_read_support_format_cab.c
+++ b/libarchive/archive_read_support_format_cab.c
@@ -3290,7 +3290,7 @@ lzx_make_huffman_table(struct huffman *hf)
 		}
 	}
 	/* Verify Kraft's inequality. */
-	if ((ptn & 0xffff) != 0 || maxbits > hf->tbl_bits)
+	if ((ptn != 0 && ptn != 0x10000) || maxbits > hf->tbl_bits)
 		return (0);/* Invalid */
 
 	hf->max_bits = maxbits;