mm: use pidfd_get_task()
Instead of duplicating the same code in two places use the newly added
pidfd_get_task() helper. This fixes an (unimportant for now) bug where
PIDTYPE_PID is used whereas PIDTYPE_TGID should have been used.
Link: https://lore.kernel.org/r/20211004125050.1153693-3-christian.brauner@ubuntu.com
Link: https://lore.kernel.org/r/20211011133245.1703103-3-brauner@kernel.org
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Matthew Bobrowski <repnop@google.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Minchan Kim <minchan@kernel.org>
Reviewed-by: Matthew Bobrowski <repnop@google.com>
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
diff --git a/mm/madvise.c b/mm/madvise.c
index 0734db8..8c92720 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -1235,7 +1235,6 @@ SYSCALL_DEFINE5(process_madvise, int, pidfd, const struct iovec __user *, vec,
struct iovec iovstack[UIO_FASTIOV], iovec;
struct iovec *iov = iovstack;
struct iov_iter iter;
- struct pid *pid;
struct task_struct *task;
struct mm_struct *mm;
size_t total_len;
@@ -1250,18 +1249,12 @@ SYSCALL_DEFINE5(process_madvise, int, pidfd, const struct iovec __user *, vec,
if (ret < 0)
goto out;
- pid = pidfd_get_pid(pidfd, &f_flags);
- if (IS_ERR(pid)) {
- ret = PTR_ERR(pid);
+ task = pidfd_get_task(pidfd, &f_flags);
+ if (IS_ERR(task)) {
+ ret = PTR_ERR(task);
goto free_iov;
}
- task = get_pid_task(pid, PIDTYPE_PID);
- if (!task) {
- ret = -ESRCH;
- goto put_pid;
- }
-
if (!process_madvise_behavior_valid(behavior)) {
ret = -EINVAL;
goto release_task;
@@ -1301,8 +1294,6 @@ SYSCALL_DEFINE5(process_madvise, int, pidfd, const struct iovec __user *, vec,
mmput(mm);
release_task:
put_task_struct(task);
-put_pid:
- put_pid(pid);
free_iov:
kfree(iov);
out: