From 7a801ba8ce7befc2309ece2ca918eb688c67fda9 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Wed, 12 Aug 2015 00:48:11 -0400 Subject: [PATCH] Fix some possible low-memory failures in regexp compilation. newnfa() failed to set the regex error state when malloc() fails. Several places in regcomp.c failed to check for an error after calling subre(). Each of these mistakes could lead to null-pointer-dereference crashes in memory-starved backends. Report and patch by Andreas Seltenreich. Back-patch to all branches. --- src/backend/regex/regc_nfa.c | 3 +++ src/backend/regex/regcomp.c | 3 +++ 2 files changed, 6 insertions(+) diff --git a/src/backend/regex/regc_nfa.c b/src/backend/regex/regc_nfa.c index 776bb59b86..e0d5af205f 100644 --- a/src/backend/regex/regc_nfa.c +++ b/src/backend/regex/regc_nfa.c @@ -52,7 +52,10 @@ newnfa(struct vars * v, nfa = (struct nfa *) MALLOC(sizeof(struct nfa)); if (nfa == NULL) + { + ERR(REG_ESPACE); return NULL; + } nfa->states = NULL; nfa->slast = NULL; diff --git a/src/backend/regex/regcomp.c b/src/backend/regex/regcomp.c index 630e2b8402..f1539e726a 100644 --- a/src/backend/regex/regcomp.c +++ b/src/backend/regex/regcomp.c @@ -941,6 +941,7 @@ parseqatom(struct vars * v, NOERR(); assert(v->nextvalue > 0); atom = subre(v, 'b', BACKR, lp, rp); + NOERR(); subno = v->nextvalue; atom->subno = subno; EMPTYARC(lp, rp); /* temporarily, so there's something */ @@ -1071,6 +1072,7 @@ parseqatom(struct vars * v, /* break remaining subRE into x{...} and what follows */ t = subre(v, '.', COMBINE(qprefer, atom->flags), lp, rp); + NOERR(); t->left = atom; atomp = &t->left; @@ -1079,6 +1081,7 @@ parseqatom(struct vars * v, /* split top into prefix and remaining */ assert(top->op == '=' && top->left == NULL && top->right == NULL); top->left = subre(v, '=', top->flags, top->begin, lp); + NOERR(); top->op = '.'; top->right = t; -- 2.50.0