From 5c0d6230f54c97c3fa5cf9a7cc286c35ebaad766 Mon Sep 17 00:00:00 2001 From: Tom Lane <tgl@sss.pgh.pa.us> Date: Sat, 2 Jan 2016 16:24:50 -0500 Subject: [PATCH] Fix overly-strict assertions in spgtextproc.c. spg_text_inner_consistent is capable of reconstructing an empty string to pass down to the next index level; this happens if we have an empty string coming in, no prefix, and a dummy node label. (In practice, what is needed to trigger that is insertion of a whole bunch of empty-string values.) Then, we will arrive at the next level with in->level == 0 and a non-NULL (but zero length) in->reconstructedValue, which is valid but the Assert tests weren't expecting it. Per report from Andreas Seltenreich. This has no impact in non-Assert builds, so should not be a problem in production, but back-patch to all affected branches anyway. In passing, remove a couple of useless variable initializations and shorten the code by not duplicating DatumGetPointer() calls. --- src/backend/access/spgist/spgtextproc.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/src/backend/access/spgist/spgtextproc.c b/src/backend/access/spgist/spgtextproc.c index fe8a41bd1c6..f8a579f4f8d 100644 --- a/src/backend/access/spgist/spgtextproc.c +++ b/src/backend/access/spgist/spgtextproc.c @@ -403,8 +403,9 @@ spg_text_inner_consistent(PG_FUNCTION_ARGS) spgInnerConsistentIn *in = (spgInnerConsistentIn *) PG_GETARG_POINTER(0); spgInnerConsistentOut *out = (spgInnerConsistentOut *) PG_GETARG_POINTER(1); bool collate_is_c = lc_collate_is_c(PG_GET_COLLATION()); - text *reconstrText = NULL; - int maxReconstrLen = 0; + text *reconstructedValue; + text *reconstrText; + int maxReconstrLen; text *prefixText = NULL; int prefixSize = 0; int i; @@ -420,8 +421,9 @@ spg_text_inner_consistent(PG_FUNCTION_ARGS) * created by a previous invocation of this routine, and we always emit * long-format reconstructed values. */ - Assert(in->level == 0 ? DatumGetPointer(in->reconstructedValue) == NULL : - VARSIZE_ANY_EXHDR(DatumGetPointer(in->reconstructedValue)) == in->level); + reconstructedValue = (text *) DatumGetPointer(in->reconstructedValue); + Assert(reconstructedValue == NULL ? in->level == 0 : + VARSIZE_ANY_EXHDR(reconstructedValue) == in->level); maxReconstrLen = in->level + 1; if (in->hasPrefix) @@ -436,7 +438,7 @@ spg_text_inner_consistent(PG_FUNCTION_ARGS) if (in->level) memcpy(VARDATA(reconstrText), - VARDATA(DatumGetPointer(in->reconstructedValue)), + VARDATA(reconstructedValue), in->level); if (prefixSize) memcpy(((char *) VARDATA(reconstrText)) + in->level, @@ -560,7 +562,7 @@ spg_text_leaf_consistent(PG_FUNCTION_ARGS) if (DatumGetPointer(in->reconstructedValue)) reconstrValue = DatumGetTextP(in->reconstructedValue); - Assert(level == 0 ? reconstrValue == NULL : + Assert(reconstrValue == NULL ? level == 0 : VARSIZE_ANY_EXHDR(reconstrValue) == level); /* Reconstruct the full string represented by this leaf tuple */ -- GitLab