From: Marc Dionne <marc.c.dionne@gmail.com>
Date: Sat, 19 Jan 2013 03:40:03 +0000 (-0500)
Subject: Linux: setpag() may replace credentials
X-Git-Url: http://git.openafs.org/?p=openafs.git;a=commitdiff_plain;h=ab752d393a4147680b03e57718f223524f8295c9;hp=a167ef4a212f04dd105186f1bccf12bdaa0eea47

Linux: setpag() may replace credentials

For recent Linux. setpag() may replace the current process' cred
structure with a new one.  This is not a problem for most callers,
but in the case of processing a SetTokens2 pioctl with the setpag
option, the new credentials should be used to determine the target
for the token.

Reviewed-on: http://gerrit.openafs.org/8924
Reviewed-by: Chas Williams - CONTRACTOR <chas@cmf.nrl.navy.mil>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
(cherry picked from commit b61eac783e8c092cd4ba9f53a2b5ca7d43e08b1b)

Change-Id: I66b5f171318964ff40fe78be24e75519183c3a82
---

diff --git a/src/afs/afs_pioctl.c b/src/afs/afs_pioctl.c
index 3c01be5..98919a3 100644
--- a/src/afs/afs_pioctl.c
+++ b/src/afs/afs_pioctl.c
@@ -1859,6 +1859,9 @@ DECL_PIOCTL(PSetTokens)
     afs_PutCell(tcell, READ_LOCK);
     if (set_parent_pag) {
 	afs_uint32 pag;
+#if defined(AFS_LINUX26_ENV)
+	afs_ucred_t *old_cred = *acred;
+#endif
 #if defined(AFS_DARWIN_ENV) || defined(AFS_XBSD_ENV)
 	char procname[256];
 	osi_procname(procname, 256);
@@ -1868,6 +1871,11 @@ DECL_PIOCTL(PSetTokens)
 #else
 	if (!setpag(acred, -1, &pag, 1)) {
 #endif
+#if defined(AFS_LINUX26_ENV)
+	    /* setpag() may have changed our credentials */
+	    *acred = crref();
+	    crfree(old_cred);
+#endif
 	    afs_InitReq(&treq, *acred);
 	    areq = &treq;
 	}