1 From ec3df00224d4b396e2ac6586ab5d25f673caa4c2 Mon Sep 17 00:00:00 2001
2 From: Mark Adler <madler@alumni.caltech.edu>
3 Date: Wed, 30 Mar 2022 11:14:53 -0700
4 Subject: [PATCH] Correct incorrect inputs provided to the CRC functions.
6 The previous releases of zlib were not sensitive to incorrect CRC
7 inputs with bits set above the low 32. This commit restores that
8 behavior, so that applications with such bugs will continue to
12 1 file changed, 4 insertions(+), 4 deletions(-)
14 diff --git a/crc32.c b/crc32.c
15 index a1bdce5c2..451887bc7 100644
18 @@ -630,7 +630,7 @@ unsigned long ZEXPORT crc32_z(crc, buf, len)
19 #endif /* DYNAMIC_CRC_TABLE */
21 /* Pre-condition the CRC */
23 + crc = (~crc) & 0xffffffff;
25 /* Compute the CRC up to a word boundary. */
26 while (len && ((z_size_t)buf & 7) != 0) {
27 @@ -749,7 +749,7 @@ unsigned long ZEXPORT crc32_z(crc, buf, len)
28 #endif /* DYNAMIC_CRC_TABLE */
30 /* Pre-condition the CRC */
32 + crc = (~crc) & 0xffffffff;
36 @@ -1077,7 +1077,7 @@ uLong ZEXPORT crc32_combine64(crc1, crc2, len2)
37 #ifdef DYNAMIC_CRC_TABLE
38 once(&made, make_crc_table);
39 #endif /* DYNAMIC_CRC_TABLE */
40 - return multmodp(x2nmodp(len2, 3), crc1) ^ crc2;
41 + return multmodp(x2nmodp(len2, 3), crc1) ^ (crc2 & 0xffffffff);
44 /* ========================================================================= */
45 @@ -1112,5 +1112,5 @@ uLong crc32_combine_op(crc1, crc2, op)
49 - return multmodp(op, crc1) ^ crc2;
50 + return multmodp(op, crc1) ^ (crc2 & 0xffffffff);