Thread: pgsql: Fix subscriber invalid memory access on DDL.

Fix subscriber invalid memory access on DDL.

This patch allows building the local relmap cache for a subscribed
relation after processing pending invalidation messages and potential
relcache updates.  Without this, the attributes in the local cache don't
tally with the updated relcache entry leading to invalid memory access.

Reported-by Jehan-Guillaume de Rorthais
Author: Jehan-Guillaume de Rorthais and Vignesh C
Reviewed-by: Amit Kapila
Backpatch-through: 10
Discussion: https://postgr.es/m/20191025175929.7e90dbf5@firost

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/c74111d8bd6853b9944d004706dcc0cea2f2a25a

Modified Files
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src/backend/replication/logical/relation.c | 38 ++++++++++++++++++++----------
1 file changed, 25 insertions(+), 13 deletions(-)