postgres.git / summary / log / commit / refs

commit    7a801ba8ce7befc2309ece2ca918eb688c67fda9
Author:   Tom Lane <tgl@sss.pgh.pa.us>
Date:     Wed Aug 12 04:48:11 2015 +0000

    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 776bb59b867..e0d5af205f6 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 630e2b8402e..f1539e726a7 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;
 


[parent: 34f1a85e513d]