linux-kernel - [PATCH RESEND] iov_iter: Use user_read_access_begin() instead of user_access

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Sat,  1 May 2021 08:15:49 +0000 (UTC)
From:   Christophe Leroy <christophe.leroy@...roup.eu>
To:     Alexander Viro <viro@...iv.linux.org.uk>,
        Andrew Morton <akpm@...ux-foundation.org>
Cc:     linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
        linux-mm@...ck.org
Subject: [PATCH RESEND] iov_iter: Use user_read_access_begin() instead of
 user_access_begin()

copy_compat_iovec_from_user() only do unsafe_get_user(),
it only requires read access.

Signed-off-by: Christophe Leroy <christophe.leroy@...roup.eu>
---
Resending with mm list in addition

 lib/iov_iter.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 61228a6c69f8..fd9bd229d51d 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -1932,7 +1932,7 @@ static int copy_compat_iovec_from_user(struct iovec *iov,
 		(const struct compat_iovec __user *)uvec;
 	int ret = -EFAULT, i;
 
-	if (!user_access_begin(uiov, nr_segs * sizeof(*uiov)))
+	if (!user_read_access_begin(uiov, nr_segs * sizeof(*uiov)))
 		return -EFAULT;
 
 	for (i = 0; i < nr_segs; i++) {
@@ -1953,7 +1953,7 @@ static int copy_compat_iovec_from_user(struct iovec *iov,
 
 	ret = 0;
 uaccess_end:
-	user_access_end();
+	user_read_access_end();
 	return ret;
 }
 
-- 
2.25.0