[patch V2 6/6] select: Convert to scoped masked user access

Thomas Gleixner posted 6 patches 2 weeks, 1 day ago
[patch V2 6/6] select: Convert to scoped masked user access
Posted by Thomas Gleixner 2 weeks, 1 day ago
From: Thomas Gleixner <tglx@linutronix.de>

Replace the open coded implementation with the scoped masked user access
mechanism.

No functional change intended.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: linux-fsdevel@vger.kernel.org
---
 fs/select.c |   14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)
---
--- a/fs/select.c
+++ b/fs/select.c
@@ -776,18 +776,12 @@ static inline int get_sigset_argpack(str
 {
 	// the path is hot enough for overhead of copy_from_user() to matter
 	if (from) {
-		if (can_do_masked_user_access())
-			from = masked_user_access_begin(from);
-		else if (!user_read_access_begin(from, sizeof(*from)))
-			return -EFAULT;
-		unsafe_get_user(to->p, &from->p, Efault);
-		unsafe_get_user(to->size, &from->size, Efault);
-		user_read_access_end();
+		scoped_masked_user_rw_access(from, return -EFAULT, {
+			scoped_get_user(to->p, &from->p);
+			scoped_get_user(to->size, &from->size);
+		});
 	}
 	return 0;
-Efault:
-	user_read_access_end();
-	return -EFAULT;
 }
 
 SYSCALL_DEFINE6(pselect6, int, n, fd_set __user *, inp, fd_set __user *, outp,