pgsql: pg_controldata: Fix possible errors on corrupted pg_control

pg_controldata: Fix possible errors on corrupted pg_control

Protect against malformed timestamps. Also protect against negative WalSegSz
as it triggers division by zero:

((0x100000000UL) / (WalSegSz)) can turn into zero in

XLogFileName(xlogfilename, ControlFile->checkPointCopy.ThisTimeLineID,
segno, WalSegSz);

because if WalSegSz is -1 then by arithmetic rules in C we get
0x100000000UL / 0xFFFFFFFFFFFFFFFFUL == 0.

Author: Ilyasov Ian <ianilyasov(at)outlook(dot)com>
Author: Anton Voloshin <a(dot)voloshin(at)postgrespro(dot)ru>
Backpatch-through: 13

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/f2205448b15e991478e8ba717732fc02b5a55d09

Modified Files
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src/bin/pg_controldata/pg_controldata.c | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)