postgres.git / summary / log / commit / refs

commit    4e46c97fde42fa8ca57d29b9b47f2ebd11ab8105
Author:   Tom Lane <tgl@sss.pgh.pa.us>
Date:     Mon Jan 16 18:53:40 2017 +0000
First released in: 10.0

    Fix NULL pointer dereference in tuplesort.c.
    
    Oversight in commit e94568ecc.  This could cause a crash when an external
    datum tuplesort of a pass-by-value type required multiple passes.
    Per report from Mithun Cy.
    
    Peter Geoghegan
    
    Discussion: https://postgr.es/m/CAD__OujuhfWFULGFSt1fyHqUb8N-XafjJhudwt88V0Qs2o84qg@mail.gmail.com


 src/backend/utils/sort/tuplesort.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index cbaf009cdfc..e1e692d5f0f 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2800,7 +2800,8 @@ mergeonerun(Tuplesortstate *state)
 		WRITETUP(state, destTape, &state->memtuples[0]);
 
 		/* recycle the slot of the tuple we just wrote out, for the next read */
-		RELEASE_SLAB_SLOT(state, state->memtuples[0].tuple);
+		if (state->memtuples[0].tuple)
+			RELEASE_SLAB_SLOT(state, state->memtuples[0].tuple);
 
 		/*
 		 * pull next tuple from the tape, and replace the written-out tuple in


[parent: fcf708623e86]