postgres.git / summary / log / commit / refs

commit    a35a527f2d6b28f78e9eab42801ec0170ffcb898
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 3487734a64e..27998d688a8 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 ef1d35b0aa9..72b0d76af68 100644
--- a/src/backend/regex/regcomp.c
+++ b/src/backend/regex/regcomp.c
@@ -942,6 +942,7 @@ 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 */
@@ -1076,6 +1077,7 @@ 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;
 
@@ -1084,6 +1086,7 @@ 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: e9a080d36928]