Fix dangling smgr_owner pointer when a fake relcache entry is freed.
A fake relcache entry can "own" a SmgrRelation object, like a regular
relcache entry. But when it was free'd, the owner field in SmgrRelation
was not cleared, so it was left pointing to free'd memory.
Amazingly this apparently hasn't caused crashes in practice, or we would've
heard about it earlier. Andres found this with Valgrind.
Report and fix by Andres Freund, with minor modifications by me. Backpatch
to all supported versions.
Branch
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REL8_4_STABLE
Details
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http://git.postgresql.org/pg/commitdiff/d411d6eff1b7e91de0fecece08acc6b6eca04d6d
Modified Files
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src/backend/access/transam/xlogutils.c | 3 +++
src/backend/storage/smgr/smgr.c | 18 ++++++++++++++++++
src/include/storage/smgr.h | 1 +
3 files changed, 22 insertions(+)