Thread: pgsql: Ensure Soundex difference() function handles empty input sanely.
Ensure Soundex difference() function handles empty input sanely. fuzzystrmatch's difference() function assumes that _soundex() always initializes its output buffer fully. This was not so for the case of a string containing no alphabetic characters, resulting in unstable output and Valgrind complaints. Fix by using memset() to fill the whole buffer in the early-exit case. Also make some cosmetic improvements (I didn't care for the random switches between "instr[0]" and "*instr" notation). Report and diagnosis by Alexander Lakhin (bug #17935). Back-patch to all supported branches. Discussion: https://postgr.es/m/17935-b99316aa79c18513@postgresql.org Branch ------ REL_14_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/ccd3623256220b944d9da00df75d91ef4d550362 Modified Files -------------- contrib/fuzzystrmatch/expected/fuzzystrmatch.out | 6 ++++++ contrib/fuzzystrmatch/fuzzystrmatch.c | 15 ++++++++------- contrib/fuzzystrmatch/sql/fuzzystrmatch.sql | 1 + 3 files changed, 15 insertions(+), 7 deletions(-)