In array_position()/array_positions(), beware of empty input array.
These functions incautiously fetched the array's first lower bound
even when the array is zero-dimensional, thus fetching the word
after the allocated array space. While almost always harmless,
with very bad luck this could result in SIGSEGV. Fix by adding
an early exit for empty input.
Per bug #17920 from Alexander Lakhin.
Discussion: https://postgr.es/m/17920-f7c228c627b6d02e%40postgresql.org
Branch
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REL_11_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/4624aad61a313520d6542a210680088cec644dca
Modified Files
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src/backend/utils/adt/array_userfuncs.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)