---

yaml --- r: 146422 b: refs/heads/master c: 5e751e9 h: refs/heads/master v: v3
git-mirror · May 10, 2009 · 7478e9f · 7478e9f
1 parent d107fcf
commit 7478e9f
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Showing 7 changed files with 21 additions and 18 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d254117099d711f215e62427f55dfb8ebd5ad011
+refs/heads/master: 5e751e992f3fb08ba35e1ca8095ec8fbf9eda523
diff --git a/trunk/fs/compat.c b/trunk/fs/compat.c
@@ -1488,7 +1488,7 @@ int compat_do_execve(char * filename,
 	if (!bprm)
 		goto out_files;
 
-	retval = mutex_lock_interruptible(&current->cred_exec_mutex);
+	retval = mutex_lock_interruptible(&current->cred_guard_mutex);
 	if (retval < 0)
 		goto out_free;
 	current->in_execve = 1;
@@ -1550,7 +1550,7 @@ int compat_do_execve(char * filename,
 	/* execve succeeded */
 	current->fs->in_exec = 0;
 	current->in_execve = 0;
-	mutex_unlock(&current->cred_exec_mutex);
+	mutex_unlock(&current->cred_guard_mutex);
 	acct_update_integrals(current);
 	free_bprm(bprm);
 	if (displaced)
@@ -1573,7 +1573,7 @@ int compat_do_execve(char * filename,
 
 out_unlock:
 	current->in_execve = 0;
-	mutex_unlock(&current->cred_exec_mutex);
+	mutex_unlock(&current->cred_guard_mutex);
 
 out_free:
 	free_bprm(bprm);

diff --git a/trunk/fs/exec.c b/trunk/fs/exec.c
@@ -1045,7 +1045,7 @@ void install_exec_creds(struct linux_binprm *bprm)
 	commit_creds(bprm->cred);
 	bprm->cred = NULL;
 
-	/* cred_exec_mutex must be held at least to this point to prevent
+	/* cred_guard_mutex must be held at least to this point to prevent
 	 * ptrace_attach() from altering our determination of the task's
 	 * credentials; any time after this it may be unlocked */
 
@@ -1055,7 +1055,7 @@ EXPORT_SYMBOL(install_exec_creds);
 
 /*
  * determine how safe it is to execute the proposed program
- * - the caller must hold current->cred_exec_mutex to protect against
+ * - the caller must hold current->cred_guard_mutex to protect against
  *   PTRACE_ATTACH
  */
 int check_unsafe_exec(struct linux_binprm *bprm)
@@ -1297,7 +1297,7 @@ int do_execve(char * filename,
 	if (!bprm)
 		goto out_files;
 
-	retval = mutex_lock_interruptible(&current->cred_exec_mutex);
+	retval = mutex_lock_interruptible(&current->cred_guard_mutex);
 	if (retval < 0)
 		goto out_free;
 	current->in_execve = 1;
@@ -1360,7 +1360,7 @@ int do_execve(char * filename,
 	/* execve succeeded */
 	current->fs->in_exec = 0;
 	current->in_execve = 0;
-	mutex_unlock(&current->cred_exec_mutex);
+	mutex_unlock(&current->cred_guard_mutex);
 	acct_update_integrals(current);
 	free_bprm(bprm);
 	if (displaced)
@@ -1383,7 +1383,7 @@ int do_execve(char * filename,
 
 out_unlock:
 	current->in_execve = 0;
-	mutex_unlock(&current->cred_exec_mutex);
+	mutex_unlock(&current->cred_guard_mutex);
 
 out_free:
 	free_bprm(bprm);

diff --git a/trunk/include/linux/init_task.h b/trunk/include/linux/init_task.h
@@ -145,8 +145,8 @@ extern struct cred init_cred;
 	.group_leader	= &tsk,						\
 	.real_cred	= &init_cred,					\
 	.cred		= &init_cred,					\
-	.cred_exec_mutex =						\
-		 __MUTEX_INITIALIZER(tsk.cred_exec_mutex),		\
+	.cred_guard_mutex =						\
+		 __MUTEX_INITIALIZER(tsk.cred_guard_mutex),		\
 	.comm		= "swapper",					\
 	.thread		= INIT_THREAD,					\
 	.fs		= &init_fs,					\

diff --git a/trunk/include/linux/sched.h b/trunk/include/linux/sched.h
@@ -1247,7 +1247,9 @@ struct task_struct {
 					 * credentials (COW) */
 	const struct cred *cred;	/* effective (overridable) subjective task
 					 * credentials (COW) */
-	struct mutex cred_exec_mutex;	/* execve vs ptrace cred calculation mutex */
+	struct mutex cred_guard_mutex;	/* guard against foreign influences on
+					 * credential calculations
+					 * (notably. ptrace) */
 
 	char comm[TASK_COMM_LEN]; /* executable name excluding path
 				     - access with [gs]et_task_comm (which lock

diff --git a/trunk/kernel/cred.c b/trunk/kernel/cred.c
@@ -167,7 +167,7 @@ EXPORT_SYMBOL(prepare_creds);
 
 /*
  * Prepare credentials for current to perform an execve()
- * - The caller must hold current->cred_exec_mutex
+ * - The caller must hold current->cred_guard_mutex
  */
 struct cred *prepare_exec_creds(void)
 {
@@ -276,7 +276,7 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags)
 	struct cred *new;
 	int ret;
 
-	mutex_init(&p->cred_exec_mutex);
+	mutex_init(&p->cred_guard_mutex);
 
 	if (
 #ifdef CONFIG_KEYS

diff --git a/trunk/kernel/ptrace.c b/trunk/kernel/ptrace.c
@@ -185,10 +185,11 @@ int ptrace_attach(struct task_struct *task)
 	if (same_thread_group(task, current))
 		goto out;
 
-	/* Protect exec's credential calculations against our interference;
-	 * SUID, SGID and LSM creds get determined differently under ptrace.
+	/* Protect the target's credential calculations against our
+	 * interference; SUID, SGID and LSM creds get determined differently
+	 * under ptrace.
 	 */
-	retval = mutex_lock_interruptible(&task->cred_exec_mutex);
+	retval = mutex_lock_interruptible(&task->cred_guard_mutex);
 	if (retval  < 0)
 		goto out;
 
@@ -232,7 +233,7 @@ int ptrace_attach(struct task_struct *task)
 bad:
 	write_unlock_irqrestore(&tasklist_lock, flags);
 	task_unlock(task);
-	mutex_unlock(&task->cred_exec_mutex);
+	mutex_unlock(&task->cred_guard_mutex);
 out:
 	return retval;
 }