linux-kernel - [PATCH v4 07/13] locks: simplify overflow checking

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-Id: <1387460065-28269-8-git-send-email-jlayton@redhat.com>
Date:	Thu, 19 Dec 2013 08:34:19 -0500
From:	Jeff Layton <jlayton@...hat.com>
To:	linux-fsdevel@...r.kernel.org
Cc:	nfs-ganesha-devel@...ts.sourceforge.net,
	samba-technical@...ts.samba.org, linux-kernel@...r.kernel.org
Subject: [PATCH v4 07/13] locks: simplify overflow checking

From: "J. Bruce Fields" <bfields@...ldses.org>

Or maybe we don't actually care about indicating overflow in the 32-bit
case: sure we could fail if e.g. f_pos+start or f_pos+start+len would
exceed 32-bits, but do we really need to?

Signed-off-by: J. Bruce Fields <bfields@...hat.com>
---
 fs/locks.c | 23 +++++------------------
 1 file changed, 5 insertions(+), 18 deletions(-)

diff --git a/fs/locks.c b/fs/locks.c
index 863f4df..1555b05 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -344,8 +344,8 @@ static int assign_type(struct file_lock *fl, long type)
 	return 0;
 }
 
-static int flock_to_posix_lock_common(struct file *filp, struct file_lock *fl,
-					struct flock64 *l, loff_t offset_max)
+static int flock64_to_posix_lock(struct file *filp, struct file_lock *fl,
+				 struct flock64 *l)
 {
 	switch (l->l_whence) {
 	case SEEK_SET:
@@ -360,12 +360,12 @@ static int flock_to_posix_lock_common(struct file *filp, struct file_lock *fl,
 	default:
 		return -EINVAL;
 	}
-	if (l->l_start > offset_max - fl->fl_start)
+	if (l->l_start > OFFSET_MAX - fl->fl_start)
 		return -EOVERFLOW;
 	fl->fl_start += l->l_start;
 	if (fl->fl_start < 0)
 		return -EINVAL;
-	if (l->l_len > offset_max - fl->fl_start)
+	if (l->l_len > OFFSET_MAX - fl->fl_start)
 		return -EOVERFLOW;
 	if (fl->fl_start + l->l_len < 0)
 		return -EINVAL;
@@ -403,22 +403,9 @@ static int flock_to_posix_lock(struct file *filp, struct file_lock *fl,
 		.l_len = l->l_len,
 	};
 
-	/*
-	 * The use of OFFT_OFFSET_MAX here ensures we return -EOVERFLOW
-	 * if the start or end of the lock could not be represented as
-	 * an off_t, following SUSv3.
-	 */
-	return flock_to_posix_lock_common(filp, fl, &ll, OFFT_OFFSET_MAX);
+	return flock64_to_posix_lock(filp, fl, &ll);
 }
 
-#if BITS_PER_LONG == 32
-static int flock64_to_posix_lock(struct file *filp, struct file_lock *fl,
-				 struct flock64 *l)
-{
-	return flock_to_posix_lock_common(filp, fl, l, OFFSET_MAX);
-}
-#endif
-
 /* default lease lock manager operations */
 static void lease_break_callback(struct file_lock *fl)
 {
-- 
1.8.4.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/