diff options
| -rw-r--r-- | fs/proc/base.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c index fc5bc2767692..5bff4c6b8311 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2707,9 +2707,16 @@ static int do_io_accounting(struct task_struct *task, char *buffer, int whole) { struct task_io_accounting acct = task->ioac; unsigned long flags; + int result; - if (!ptrace_may_access(task, PTRACE_MODE_READ)) - return -EACCES; + result = mutex_lock_killable(&task->signal->cred_guard_mutex); + if (result) + return result; + + if (!ptrace_may_access(task, PTRACE_MODE_READ)) { + result = -EACCES; + goto out_unlock; + } if (whole && lock_task_sighand(task, &flags)) { struct task_struct *t = task; @@ -2720,7 +2727,7 @@ static int do_io_accounting(struct task_struct *task, char *buffer, int whole) unlock_task_sighand(task, &flags); } - return sprintf(buffer, + result = sprintf(buffer, "rchar: %llu\n" "wchar: %llu\n" "syscr: %llu\n" @@ -2735,6 +2742,9 @@ static int do_io_accounting(struct task_struct *task, char *buffer, int whole) (unsigned long long)acct.read_bytes, (unsigned long long)acct.write_bytes, (unsigned long long)acct.cancelled_write_bytes); +out_unlock: + mutex_unlock(&task->signal->cred_guard_mutex); + return result; } static int proc_tid_io_accounting(struct task_struct *task, char *buffer) |