From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 83910 invoked by alias); 11 Nov 2019 11:26:40 -0000 Mailing-List: contact glibc-cvs-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: , Sender: glibc-cvs-owner@sourceware.org List-Subscribe: Received: (qmail 83838 invoked by uid 9004); 11 Nov 2019 11:26:40 -0000 Date: Mon, 11 Nov 2019 11:26:00 -0000 Message-ID: <20191111112640.83837.qmail@sourceware.org> Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Andreas Schwab To: glibc-cvs@sourceware.org Subject: [glibc] Fix array bounds violation in regex matcher (bug 25149) X-Act-Checkin: glibc X-Git-Author: Andreas Schwab X-Git-Refname: refs/heads/master X-Git-Oldrev: 2e44b10b42d68d9887ccab17b76db5d7bbae4fb6 X-Git-Newrev: fc141ea78ee3d87c67b18488827fe2d89c9343e7 X-SW-Source: 2019-q4/txt/msg00301.txt.bz2 https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=fc141ea78ee3d87c67b18488827fe2d89c9343e7 commit fc141ea78ee3d87c67b18488827fe2d89c9343e7 Author: Andreas Schwab Date: Wed Oct 30 10:38:36 2019 +0100 Fix array bounds violation in regex matcher (bug 25149) If the regex has more subexpressions than the number of elements allocated in the regmatch_t array passed to regexec then proceed_next_node may access the regmatch_t array outside its bounds. No testcase added because even without this bug it would then crash in pop_fail_stack which is bug 11053. Diff: --- posix/regexec.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/posix/regexec.c b/posix/regexec.c index 3c46ac8..38b6d67 100644 --- a/posix/regexec.c +++ b/posix/regexec.c @@ -1266,10 +1266,13 @@ proceed_next_node (const re_match_context_t *mctx, Idx nregs, regmatch_t *regs, if (type == OP_BACK_REF) { Idx subexp_idx = dfa->nodes[node].opr.idx + 1; - naccepted = regs[subexp_idx].rm_eo - regs[subexp_idx].rm_so; + if (subexp_idx < nregs) + naccepted = regs[subexp_idx].rm_eo - regs[subexp_idx].rm_so; if (fs != NULL) { - if (regs[subexp_idx].rm_so == -1 || regs[subexp_idx].rm_eo == -1) + if (subexp_idx >= nregs + || regs[subexp_idx].rm_so == -1 + || regs[subexp_idx].rm_eo == -1) return -1; else if (naccepted) {