leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

CRED: Rename cred_exec_mutex to reflect that it's a guard against ptrace

Browse Source 
Rename cred_exec_mutex to reflect that it's a guard against foreign
intervention on a process's credential state, such as is made by ptrace().  The
attachment of a debugger to a process affects execve()'s calculation of the new
credential state - _and_ also setprocattr()'s calculation of that state.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This commit is contained in:
David Howells
2009-05-08 13:55:22 +01:00
committed by James Morris
parent d254117099
commit 5e751e992f
6 changed files with 20 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
kernel/cred.c
View File

@@ -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

9
kernel/ptrace.c
View File

@@ -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 @@ repeat:
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;
}