diff options
Diffstat (limited to 'kernel/ptrace.c')
| -rw-r--r-- | kernel/ptrace.c | 22 |
1 files changed, 13 insertions, 9 deletions
diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 49849d12dd1..b9d5f4e4f6a 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -115,7 +115,7 @@ int ptrace_check_attach(struct task_struct *child, int kill) int __ptrace_may_access(struct task_struct *task, unsigned int mode) { - struct cred *cred = current->cred, *tcred = task->cred; + const struct cred *cred = current_cred(), *tcred; /* May we inspect the given task? * This check is used both for attaching with ptrace @@ -125,19 +125,23 @@ int __ptrace_may_access(struct task_struct *task, unsigned int mode) * because setting up the necessary parent/child relationship * or halting the specified task is impossible. */ - uid_t uid = cred->uid; - gid_t gid = cred->gid; int dumpable = 0; /* Don't let security modules deny introspection */ if (task == current) return 0; - if ((uid != tcred->euid || - uid != tcred->suid || - uid != tcred->uid || - gid != tcred->egid || - gid != tcred->sgid || - gid != tcred->gid) && !capable(CAP_SYS_PTRACE)) + rcu_read_lock(); + tcred = __task_cred(task); + if ((cred->uid != tcred->euid || + cred->uid != tcred->suid || + cred->uid != tcred->uid || + cred->gid != tcred->egid || + cred->gid != tcred->sgid || + cred->gid != tcred->gid) && + !capable(CAP_SYS_PTRACE)) { + rcu_read_unlock(); return -EPERM; + } + rcu_read_unlock(); smp_rmb(); if (task->mm) dumpable = get_dumpable(task->mm); |