[pgpool-committers: 7287] pgpool: Fix file swapping race condition in pool_passwd.

[Tatsuo Ishii]

Fix file swapping race condition in pool_passwd.

Existing implementation first stats pool passwd file and then open the
file. To prevent file-swapping due to file race conditions, open the
key file before checking it by stat().

Patch by: Masaya Kawamoto

Branch
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V4_2_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=86d4dd0ec4816764cfe1caa2c964fb6efb0952e6

Modified Files
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src/auth/pool_passwd.c | 20 ++++++++++++++------
1 file changed, 14 insertions(+), 6 deletions(-)