From 583dd860d5b833037175247230a328f0050dbfe9 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Mon, 21 Jan 2019 11:08:13 -0800
Subject: [PATCH] regex: fix read overrun [BZ #24114]
Problem found by AddressSanitizer, reported by Hongxu Chen in:
https://debbugs.gnu.org/34140
* posix/regexec.c (proceed_next_node):
Do not read past end of input buffer.
---
posix/regexec.c | 6 ++++--
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/posix/regexec.c b/posix/regexec.c
index 91d5a79..084b122 100644
--- a/posix/regexec.c
+++ b/posix/regexec.c
@@ -1293,8 +1293,10 @@ proceed_next_node (const re_match_context_t *mctx, Idx nregs, regmatch_t *regs,
else if (naccepted)
{
char *buf = (char *) re_string_get_buffer (&mctx->input);
- if (memcmp (buf + regs[subexp_idx].rm_so, buf + *pidx,
- naccepted) != 0)
+ if (mctx->input.valid_len - *pidx < naccepted
+ || (memcmp (buf + regs[subexp_idx].rm_so, buf + *pidx,
+ naccepted)
+ != 0))
return -1;
}
}
--
2.9.3