SECURITY: length limits on many cmdline options

We'll also now abort upon, rather than silently truncate, a driver name
(router, transport, ACL, etc) encountered in the config which is longer than
the 64-char limit.

(cherry picked from commit ff8bef9ae2370db4a7873fe2ce573a607fe6999f)
(cherry picked from commit a8bd24b96c2027fd839f95a9e6b3282453ae288e)

2 files changed, 25 insertions, 0 deletions

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index 9b8c92bbd..61abb70c0 100644
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -51,6 +51,8 @@
 .set ACL "access control lists (ACLs)"
 .set I   "    "
 
+.set drivernamemax "64"
+
 .macro copyyear
 2020
 .endmacro
@@ -18802,6 +18804,11 @@ which the preconditions are tested. The order of expansion of the options that
 provide data for a transport is: &%errors_to%&, &%headers_add%&,
 &%headers_remove%&, &%transport%&.
 
+.new
+The name of a router is limited to be &drivernamemax; ASCII characters long;
+prior to Exim 4.95 names would be silently truncated at this length, but now
+it is enforced.
+.wen
 
 
 .option address_data routers string&!! unset
@@ -22345,6 +22352,12 @@ and &$original_domain$& is never set.
 .scindex IIDgenoptra1 "generic options" "transport"
 .scindex IIDgenoptra2 "options" "generic; for transports"
 .scindex IIDgenoptra3 "transport" "generic options for"
+.new
+The name of a transport is limited to be &drivernamemax; ASCII characters long;
+prior to Exim 4.95 names would be silently truncated at this length, but now
+it is enforced.
+.wen
+
 The following generic options apply to all transports:
 
 
@@ -27181,6 +27194,12 @@ permitted to use it as a relay. SMTP authentication is not of relevance to the
 transfer of mail between servers that have no managerial connection with each
 other.
 
+.new
+The name of an authenticator is limited to be &drivernamemax; ASCII characters long;
+prior to Exim 4.95 names would be silently truncated at this length, but now
+it is enforced.
+.wen
+
 .cindex "AUTH" "description of"
 .cindex "ESMTP extensions" AUTH
 Very briefly, the way SMTP authentication works is as follows:
diff --git a/doc/doc-txt/ChangeLog b/doc/doc-txt/ChangeLog
index 58ba70f02..4c6eb810e 100644
--- a/doc/doc-txt/ChangeLog
+++ b/doc/doc-txt/ChangeLog
@@ -263,6 +263,12 @@ PP/02 Bug 2643: Correct TLS DH constants.
       incorrect Diffie-Hellman constants in the Exim source.
       Reported by kylon94, code-gen tool fix by Simon Arlott.
 
+PP/03 Fix Linux security issue CVE-2020-SLCWD and guard against PATH_MAX
+      better.  Reported by Qualys.
+
+PP/04 Impose security length checks on various command-line options.
+      Fixes CVE-2020-SPRSS reported by Qualys.
+
 
 Exim version 4.94
 -----------------