diff options
| -rw-r--r-- | contrib/amcheck/verify_heapam.c | 40 |
1 files changed, 31 insertions, 9 deletions
diff --git a/contrib/amcheck/verify_heapam.c b/contrib/amcheck/verify_heapam.c index 10dd31477b..1dc9d89f30 100644 --- a/contrib/amcheck/verify_heapam.c +++ b/contrib/amcheck/verify_heapam.c @@ -481,11 +481,35 @@ verify_heapam(PG_FUNCTION_ARGS) (unsigned) maxoff)); continue; } + + /* + * Since we've checked that this redirect points to a line + * pointer between FirstOffsetNumber and maxoff, it should + * now be safe to fetch the referenced line pointer. We expect + * it to be LP_NORMAL; if not, that's corruption. + */ rditem = PageGetItemId(ctx.page, rdoffnum); if (!ItemIdIsUsed(rditem)) + { report_corruption(&ctx, - psprintf("line pointer redirection to unused item at offset %u", + psprintf("redirected line pointer points to an unused item at offset %u", (unsigned) rdoffnum)); + continue; + } + else if (ItemIdIsDead(rditem)) + { + report_corruption(&ctx, + psprintf("redirected line pointer points to a dead item at offset %u", + (unsigned) rdoffnum)); + continue; + } + else if (ItemIdIsRedirected(rditem)) + { + report_corruption(&ctx, + psprintf("redirected line pointer points to another redirected line pointer at offset %u", + (unsigned) rdoffnum)); + continue; + } /* * Record the fact that this line pointer has passed basic @@ -584,14 +608,12 @@ verify_heapam(PG_FUNCTION_ARGS) /* Handle the cases where the current line pointer is a redirect. */ if (ItemIdIsRedirected(curr_lp)) { - /* Can't redirect to another redirect. */ - if (ItemIdIsRedirected(next_lp)) - { - report_corruption(&ctx, - psprintf("redirected line pointer points to another redirected line pointer at offset %u", - (unsigned) nextoffnum)); - continue; - } + /* + * We should not have set successor[ctx.offnum] to a value + * other than InvalidOffsetNumber unless that line pointer + * is LP_NORMAL. + */ + Assert(ItemIdIsNormal(next_lp)); /* Can only redirect to a HOT tuple. */ next_htup = (HeapTupleHeader) PageGetItem(ctx.page, next_lp); |