Fix oversight in handling of modifiedCols since f24523672d Commit f24523672d fixed a memory leak by moving the modifiedCols bitmap into the per-row memory context. In the case of AFTER UPDATE triggers, the bitmap is however referenced from an event kept until the end of the query, resulting in a use-after-free bug.
Fixed by copying the bitmap into the AfterTriggerEvents memory context, which is the one where we keep the trigger events. There's only one place that needs to do the copy, but the memory context may not exist yet. Doing that in a separate function seems more readable. Report by Alexander Pyhalov, fix by me. Backpatch to 13, where the bitmap was added to the event by commit 71d60e2aa0. Reported-by: Alexander Pyhalov Backpatch-through: 13 Discussion: https://postgr.es/m/acddb17c89b0d6cb940eaeda18c08...@postgrespro.ru Branch ------ REL_13_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/984c23f6f5926f7cfb304b8f931e9bb66174b41c Modified Files -------------- src/backend/commands/trigger.c | 33 ++++++++++++++++++++++++++++++++- 1 file changed, 32 insertions(+), 1 deletion(-)
