Upstream-Status: Backport This patch is from perl mainline: http://perl5.git.perl.org/perl.git/commit/b675304e3fdbcce3ef853b06b6ebe870d99faa7e Signed-off-by: Kang Kai --- From b675304e3fdbcce3ef853b06b6ebe870d99faa7e Mon Sep 17 00:00:00 2001 From: Andy Dougherty Date: Thu, 27 Sep 2012 09:52:18 -0400 Subject: [PATCH] avoid calling memset with a negative count Poorly written perl code that allows an attacker to specify the count to perl's 'x' string repeat operator can already cause a memory exhaustion denial-of-service attack. A flaw in versions of perl before 5.15.5 can escalate that into a heap buffer overrun; coupled with versions of glibc before 2.16, it possibly allows the execution of arbitrary code. The flaw addressed to this commit has been assigned identifier CVE-2012-5195. --- util.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/util.c b/util.c index 0ea39c6..230211e 100644 --- a/util.c +++ b/util.c @@ -3319,6 +3319,9 @@ Perl_repeatcpy(register char *to, register const char *from, I32 len, register I { PERL_ARGS_ASSERT_REPEATCPY; + if (count < 0) + Perl_croak_nocontext("%s",PL_memory_wrap); + if (len == 1) memset(to, *from, count); else if (count) { -- 1.7.4.1