[pgpool-committers: 7285] 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_0_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=053e6d8595c41fa8255d1c9f77f87cef1718c3b0

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