[dovecot/core] c398ec: lib: printf_format_fix*() - Be over-strict in what...

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/dovecot/core
  Commit: c398eca6b0fc6583687bd6fe2ee2dbcca2ae9387
      https://github.com/dovecot/core/commit/c398eca6b0fc6583687bd6fe2ee2dbcca2ae9387
  Author: Timo Sirainen <timo.sirainen at dovecot.fi>
  Date:   2017-10-18 (Wed, 18 Oct 2017)

  Changed paths:
    M src/lib/printf-format-fix.c
    M src/lib/test-printf-format-fix.c

  Log Message:
  -----------
  lib: printf_format_fix*() - Be over-strict in what format strings are allowed

The checks could have been bypassed by some invalid format strings that were
handled differently by the printf_format_fix*() code and libc. For example
"%**%n" was passed through as ok, but glibc handled the %n in it.

Found by cPanel Security Team.