From 20e6c868c29f5a6121cbb88f3387bb9b884a4206 Mon Sep 17 00:00:00 2001 From: Arjun Shankar Date: Wed, 4 Nov 2020 12:19:38 +0100 Subject: [PATCH] iconv: Accept redundant shift sequences in IBM1364 [BZ #26224] The IBM1364, IBM1371, IBM1388, IBM1390 and IBM1399 character sets share converter logic (iconvdata/ibm1364.c) which would reject redundant shift sequences when processing input in these character sets. This led to a hang in the iconv program (CVE-2020-27618). This commit adjusts the converter to ignore redundant shift sequences and adds test cases for iconv_prog hangs that would be triggered upon their rejection. This brings the implementation in line with other converters that also ignore redundant shift sequences (e.g. IBM930 etc., fixed in commit 692de4b3960d). Reviewed-by: Carlos O'Donell Upstream-Status: Backport [https://sourceware.org/git/?p=glibc.git;a=commit; h=9a99c682144bdbd40792ebf822fe9264e0376fb5] CVE: CVE-2020-27618 Signed-off-by: Yi Fan Yu --- iconv/tst-iconv_prog.sh | 16 ++++++++++------ iconvdata/ibm1364.c | 14 ++------------ 2 files changed, 12 insertions(+), 18 deletions(-) diff --git a/iconv/tst-iconv_prog.sh b/iconv/tst-iconv_prog.sh index 8298136b7f..d8db7b335c 100644 --- a/iconv/tst-iconv_prog.sh +++ b/iconv/tst-iconv_prog.sh @@ -102,12 +102,16 @@ hangarray=( "\x00\x80;-c;IBM1161;UTF-8//TRANSLIT//IGNORE" "\x00\xdb;-c;IBM1162;UTF-8//TRANSLIT//IGNORE" "\x00\x70;-c;IBM12712;UTF-8//TRANSLIT//IGNORE" -# These are known hangs that are yet to be fixed: -# "\x00\x0f;-c;IBM1364;UTF-8" -# "\x00\x0f;-c;IBM1371;UTF-8" -# "\x00\x0f;-c;IBM1388;UTF-8" -# "\x00\x0f;-c;IBM1390;UTF-8" -# "\x00\x0f;-c;IBM1399;UTF-8" +"\x00\x0f;-c;IBM1364;UTF-8" +"\x0e\x0e;-c;IBM1364;UTF-8" +"\x00\x0f;-c;IBM1371;UTF-8" +"\x0e\x0e;-c;IBM1371;UTF-8" +"\x00\x0f;-c;IBM1388;UTF-8" +"\x0e\x0e;-c;IBM1388;UTF-8" +"\x00\x0f;-c;IBM1390;UTF-8" +"\x0e\x0e;-c;IBM1390;UTF-8" +"\x00\x0f;-c;IBM1399;UTF-8" +"\x0e\x0e;-c;IBM1399;UTF-8" "\x00\x53;-c;IBM16804;UTF-8//TRANSLIT//IGNORE" "\x00\x41;-c;IBM274;UTF-8//TRANSLIT//IGNORE" "\x00\x41;-c;IBM275;UTF-8//TRANSLIT//IGNORE" diff --git a/iconvdata/ibm1364.c b/iconvdata/ibm1364.c index 49e7267ab4..521f0825b7 100644 --- a/iconvdata/ibm1364.c +++ b/iconvdata/ibm1364.c @@ -158,24 +158,14 @@ enum \ if (__builtin_expect (ch, 0) == SO) \ { \ - /* Shift OUT, change to DBCS converter. */ \ - if (curcs == db) \ - { \ - result = __GCONV_ILLEGAL_INPUT; \ - break; \ - } \ + /* Shift OUT, change to DBCS converter (redundant escape okay). */ \ curcs = db; \ ++inptr; \ continue; \ } \ if (__builtin_expect (ch, 0) == SI) \ { \ - /* Shift IN, change to SBCS converter. */ \ - if (curcs == sb) \ - { \ - result = __GCONV_ILLEGAL_INPUT; \ - break; \ - } \ + /* Shift IN, change to SBCS converter (redundant escape okay). */ \ curcs = sb; \ ++inptr; \ continue; \ -- 2.29.2