From 6b78dfd86b358e469916fd72ac2f3640caa21a34 Mon Sep 17 00:00:00 2001
From: Chas Williams <chas@cmf.nrl.navy.mil>
Date: Wed, 6 Sep 2006 21:57:17 +0000
Subject: [PATCH] STABLE14-keyring-dont-use-syscall2-20060906

avoid not-really-portable-use of syscall2


(cherry picked from commit 3dc9bcb1289bb868a336e820d589b03246c36bce)
---
 src/afs/LINUX/osi_groups.c | 68 +++++++++++++++++++++++++++++++++-----
 src/afs/sysincludes.h      |  3 ++
 src/cf/linux-test4.m4      |  6 +---
 3 files changed, 63 insertions(+), 14 deletions(-)

diff --git a/src/afs/LINUX/osi_groups.c b/src/afs/LINUX/osi_groups.c
index 1409624f78..c4a0514dd5 100644
--- a/src/afs/LINUX/osi_groups.c
+++ b/src/afs/LINUX/osi_groups.c
@@ -189,16 +189,60 @@ __setpag(cred_t **cr, afs_uint32 pagvalue, afs_uint32 *newpag,
 }
 
 #ifdef LINUX_KEYRING_SUPPORT
-#include <asm/unistd.h>
-#include <linux/keyctl.h>
+static struct key_type *__key_type_keyring;
 
-static int errno;
-static inline _syscall2(long, keyctl, int, option, void*, arg2);
-
-static long
-__join_session_keyring(char *name)
+static int
+install_session_keyring(struct task_struct *task, struct key *keyring)
 {
-	return keyctl(KEYCTL_JOIN_SESSION_KEYRING, name);
+    struct key *old;
+    char desc[20];
+    unsigned long not_in_quota;
+    int code = -EINVAL;
+
+    if (!__key_type_keyring)
+	return code;
+
+    if (!keyring) {
+
+	/* create an empty session keyring */
+	not_in_quota = KEY_ALLOC_IN_QUOTA;
+	sprintf(desc, "_ses.%u", task->tgid);
+
+#ifdef KEY_ALLOC_NEEDS_STRUCT_TASK
+	keyring = key_alloc(__key_type_keyring, desc,
+			    task->uid, task->gid, task,
+			    (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL,
+			    not_in_quota);
+#else
+	keyring = key_alloc(__key_type_keyring, desc,
+			    task->uid, task->gid,
+			    (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL,
+			    not_in_quota);
+#endif
+	if (IS_ERR(keyring)) {
+	    code = PTR_ERR(keyring);
+	    goto out;
+	}
+    }
+
+    code = key_instantiate_and_link(keyring, NULL, 0, NULL, NULL);
+    if (code < 0) {
+	key_put(keyring);
+	goto out;
+    }
+
+    /* install the keyring */
+    spin_lock_irq(&task->sighand->siglock);
+    old = task->signal->session_keyring;
+    smp_wmb();
+    task->signal->session_keyring = keyring;
+    spin_unlock_irq(&task->sighand->siglock);
+
+    if (old)
+	    key_put(old);
+
+out:
+    return code;
 }
 #endif /* LINUX_KEYRING_SUPPORT */
 
@@ -255,7 +299,7 @@ setpag(cred_t **cr, afs_uint32 pagvalue, afs_uint32 *newpag,
 #ifdef LINUX_KEYRING_SUPPORT
     if (code == 0) {
 
-	(void) __join_session_keyring(NULL);
+	(void) install_session_keyring(current, NULL);
 
 	if (current->signal->session_keyring) {
 	    struct key *key;
@@ -520,6 +564,12 @@ struct key_type key_type_afs_pag =
 
 void osi_keyring_init(void)
 {
+    struct task_struct *p;
+
+    p = find_task_by_pid(1);
+    if (p && p->user->session_keyring)
+	__key_type_keyring = p->user->session_keyring->type;
+
     register_key_type(&key_type_afs_pag);
 }
 
diff --git a/src/afs/sysincludes.h b/src/afs/sysincludes.h
index 22fe7a684e..df31f0f534 100644
--- a/src/afs/sysincludes.h
+++ b/src/afs/sysincludes.h
@@ -73,6 +73,9 @@
 #if defined(LINUX_KEYRING_SUPPORT)
 #include <linux/rwsem.h>
 #include <linux/key.h>
+#ifndef KEY_ALLOC_IN_QUOTA
+#define KEY_ALLOC_IN_QUOTA 1
+#endif
 #endif
 #endif
 /* Avoid conflicts with coda overloading AFS type namespace. Must precede
diff --git a/src/cf/linux-test4.m4 b/src/cf/linux-test4.m4
index 9c2e0dfb85..5485b2f232 100644
--- a/src/cf/linux-test4.m4
+++ b/src/cf/linux-test4.m4
@@ -614,12 +614,8 @@ AC_DEFUN([LINUX_LINUX_KEYRING_SUPPORT], [
     AC_TRY_KBUILD(
 [#include <linux/rwsem.h>
 #include <linux/key.h>
-#include <linux/keyctl.h>
-#include <asm/unistd.h>
-static int errno;
-static inline _syscall2(long, keyctl, int, option, void*, arg2);],
+#include <linux/keyctl.h>],
 [#ifdef CONFIG_KEYS
-keyctl(KEYCTL_JOIN_SESSION_KEYRING, NULL);
 request_key(NULL, NULL, NULL);
 #if !defined(KEY_POS_VIEW) || !defined(KEY_POS_SEARCH)
 #error "Your linux/key.h does not contain KEY_POS_VIEW or KEY_POS_SEARCH"