From: Eric Blake <eblake@redhat.com>
Date: Wed, 2 Mar 2011 23:25:57 +0000 (-0700)
Subject: util: correct retry path in virFileOperation
X-Git-Tag: CVE-2011-1146~75
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d152f647606a86992b775c4241ba09dce47fd063;p=thirdparty%2Flibvirt.git

util: correct retry path in virFileOperation

In virFileOperation, the parent does a fallback to a non-fork
attempt if it detects that the child returned EACCES.  However,
the child was calling _exit(-EACCES), which does _not_ appear
as EACCES in the parent.

* src/util/util.c (virFileOperation): Correctly pass EACCES from
child to parent.
---

diff --git a/src/util/util.c b/src/util/util.c
index bac71c80c2..f41e117d39 100644
--- a/src/util/util.c
+++ b/src/util/util.c
@@ -1559,6 +1559,15 @@ parenterror:
         goto childerror;
     }
 childerror:
+    /* ret tracks -errno on failure, but exit value must be positive.
+     * If the child exits with EACCES, then the parent tries again.  */
+    /* XXX This makes assumptions about errno being < 255, which is
+     * not true on Hurd.  */
+    ret = -ret;
+    if ((ret & 0xff) != ret) {
+        VIR_WARN("unable to pass desired return value %d", ret);
+        ret = 0xff;
+    }
     _exit(ret);
 
 }