Package: bzip2 / 1.0.6-9.2~deb10u1

Make-sure-nSelectors-is-not-out-of-range.patch Patch series | download
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From: Albert Astals Cid <aacid@kde.org>
Date: Tue, 28 May 2019 19:35:18 +0200
Subject: Make sure nSelectors is not out of range
Origin: https://gitlab.com/federicomenaquintero/bzip2/commit/74de1e2e6ffc9d51ef9824db71a8ffee5962cdbc
Bug-Debian-Security: https://security-tracker.debian.org/tracker/CVE-2019-12900
Bug-Debian: https://bugs.debian.org/930886

nSelectors is used in a loop from 0 to nSelectors to access selectorMtf
which is
	UChar    selectorMtf[BZ_MAX_SELECTORS];
so if nSelectors is bigger than BZ_MAX_SELECTORS it'll do an invalid memory
access

Fixes out of bounds access discovered while fuzzying karchive
---
 decompress.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/decompress.c b/decompress.c
index ab6a624db17a..f3db91d14f6e 100644
--- a/decompress.c
+++ b/decompress.c
@@ -287,7 +287,7 @@ Int32 BZ2_decompress ( DState* s )
       GET_BITS(BZ_X_SELECTOR_1, nGroups, 3);
       if (nGroups < 2 || nGroups > 6) RETURN(BZ_DATA_ERROR);
       GET_BITS(BZ_X_SELECTOR_2, nSelectors, 15);
-      if (nSelectors < 1) RETURN(BZ_DATA_ERROR);
+      if (nSelectors < 1 || nSelectors > BZ_MAX_SELECTORS) RETURN(BZ_DATA_ERROR);
       for (i = 0; i < nSelectors; i++) {
          j = 0;
          while (True) {
-- 
2.20.1