Changeset d7eec4e in mod_gnutls

Timestamp:

Feb 23, 2023, 5:55:53 AM (4 weeks ago)

Author:

Fiona Klute <fiona.klute@…>

Branches:

main, master

Children:

b732220

Parents:

3855d9e

Message:

Fix loop in blocking read on transport timeout

The loop was cased by an incorrect errno if the transport read in
mgs_transport_read() fails with an APR TIMEUP status, as happens when
mod_reqtimeout limits are exceeded. Setting the transport errno to
EGAIN meant that a blocking read would be retried endlessly, setting
ETIMEDOUT instead makes the read fail as it should.

The bug was introduced in commit 92cb0cca41af946055307e373b6ab6d76d34f356,
first release to include it was 0.9.0.

Many thanks to Félix Arreola Rodríguez for the detailed analysis [1]
on the Debian bug tracker!

[1] ​https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=942737#25

File:

• src/gnutls_io.c (modified) (3 diffs)

src/gnutls_io.c

@@ -3 +3 @@
  *  Copyright 2008 Nikos Mavrogiannopoulos
  *  Copyright 2011 Dash Shendy
- *  Copyright 2015-2020 Fiona Klute
+ *  Copyright 2015-2022 Fiona Klute
  *
  *  Licensed under the Apache License, Version 2.0 (the "License");
@@ -278 +278 @@
                 ctxt->input_rc = APR_EGENERAL;
                 break;
+            } else if (rc == GNUTLS_E_PULL_ERROR
+                       && APR_STATUS_IS_TIMEUP(ctxt->input_rc)) {
+                ap_log_cerror(
+                    APLOG_MARK, APLOG_TRACE2, ctxt->input_rc, ctxt->c,
+                    "%s: transport read timed out", __func__);
             } else {
                 /* Some Other Error. Report it. Die. */
@@ -1004 +1009 @@
         {
             ctxt->input_rc = rc;
-            gnutls_transport_set_errno(ctxt->session, EAGAIN);
+            gnutls_transport_set_errno(ctxt->session, ETIMEDOUT);
             return -1;
         }