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Message-ID: <b6a1e52b-d808-4df7-87f7-2ff48d15003e@gmail.com>
Date: Sat, 18 Oct 2025 13:26:40 -0500
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To: pgsql-hackers@postgresql.org
From: Bryan Green <dbryan.green@gmail.com>
Subject: [PATCH] Fix POSIX compliance in pgwin32_unsetenv()
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I noticed that pgwin32_unsetenv() in src/port/win32env.c lacks the input 
validation that its sibling function pgwin32_setenv() has (lines 126-132).

Without these checks, the function will crash on NULL input via 
strlen(NULL), and will accept empty strings or strings containing '=' in 
violation of POSIX.1-2008.

The attached patch adds the same validation that pgwin32_setenv already 
does, making the two functions consistent.  This is purely defensive - 
it only affects callers passing invalid arguments.

regards,

Bryan Green


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