syslog: Heap buffer overflow in __vsyslog_internal

__vsyslog_internal did not handle a case where printing a SYSLOG_HEADER
containing a long program name failed to update the required buffer
size, leading to the allocation and overflow of a too-small buffer on
the heap.

CVE-Id: CVE-2023-6246
Public-Date: 2024-01-30
Vulnerable-Commit: 52a5be0df411ef3ff45c10c7c308cb92993d15b1 (2.37)
Fix-Commit: 6bd0e4efcc78f3c0115e5ea9739a1642807450da (2.39)
Fix-Commit: 23514c72b780f3da097ecf33a793b7ba9c2070d2 (2.38-42)
Fix-Commit: 97a4292aa4a2642e251472b878d0ec4c46a0e59a (2.37-57)
Vulnerable-Commit: b0e7888d1fa2dbd2d9e1645ec8c796abf78880b9 (2.36-16)
Fix-Commit: d1a83b6767f68b3cb5b4b4ea2617254acd040c82 (2.36-126)