Fix CVE-2015-8863 (Off-by-one error in the tokenadd function in jv_parse.c in jq allows remote attackers to cause a denial of service (crash) via a long JSON-encoded number, which triggers a heap-based buffer overflow): Copied from upstream code repository: From 8eb1367ca44e772963e704a700ef72ae2e12babd Mon Sep 17 00:00:00 2001 From: Nicolas Williams Date: Sat, 24 Oct 2015 17:24:57 -0500 Subject: [PATCH] Heap buffer overflow in tokenadd() (fix #105) This was an off-by one: the NUL terminator byte was not allocated on resize. This was triggered by JSON-encoded numbers longer than 256 bytes. --- jv_parse.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/jv_parse.c b/jv_parse.c index 3102ed4..84245b8 100644 --- a/jv_parse.c +++ b/jv_parse.c @@ -383,7 +383,7 @@ static pfunc stream_token(struct jv_parser* p, char ch) { static void tokenadd(struct jv_parser* p, char c) { assert(p->tokenpos <= p->tokenlen); - if (p->tokenpos == p->tokenlen) { + if (p->tokenpos >= (p->tokenlen - 1)) { p->tokenlen = p->tokenlen*2 + 256; p->tokenbuf = jv_mem_realloc(p->tokenbuf, p->tokenlen); } @@ -485,7 +485,7 @@ static pfunc check_literal(struct jv_parser* p) { TRY(value(p, v)); } else { // FIXME: better parser - p->tokenbuf[p->tokenpos] = 0; // FIXME: invalid + p->tokenbuf[p->tokenpos] = 0; char* end = 0; double d = jvp_strtod(&p->dtoa, p->tokenbuf, &end); if (end == 0 || *end != 0) value='author'>author