From c20d416b98147127fba9e1430d8763e80b524d2a Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@kernel.dk>
Date: Fri, 10 Sep 2021 11:19:58 -0600
Subject: [PATCH] Revert "iov_iter: track truncated size"
Git-commit: 7dedd3e18077f996a10c47250ac85d080e5f474e
Patch-mainline: v5.15-rc2
References: bsc#1198968 CVE-2022-1508

This reverts commit 2112ff5ce0c1128fe7b4d19cfe7f2b8ce5b595fa.

We no longer need to track the truncation count, the one user that did
need it has been converted to using iov_iter_restore() instead.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Acked-by: David Disseldorp <ddiss@suse.de>

---
 include/linux/uio.h | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/include/linux/uio.h b/include/linux/uio.h
index 984c4ab74859..207101a9c5c3 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -53,7 +53,6 @@ struct iov_iter {
 		};
 		loff_t xarray_start;
 	};
-	size_t truncated;
 };
 
 static inline enum iter_type iov_iter_type(const struct iov_iter *i)
@@ -270,10 +269,8 @@ static inline void iov_iter_truncate(struct iov_iter *i, u64 count)
 	 * conversion in assignement is by definition greater than all
 	 * values of size_t, including old i->count.
 	 */
-	if (i->count > count) {
-		i->truncated += i->count - count;
+	if (i->count > count)
 		i->count = count;
-	}
 }
 
 /*
@@ -282,7 +279,6 @@ static inline void iov_iter_truncate(struct iov_iter *i, u64 count)
  */
 static inline void iov_iter_reexpand(struct iov_iter *i, size_t count)
 {
-	i->truncated -= count - i->count;
 	i->count = count;
 }
 
-- 
2.35.3