From 684666e51585f3b136a3f505f8173d7580bc52cd Mon Sep 17 00:00:00 2001
From: Fabian Frederick <fabf@skynet.be>
Date: Mon, 23 Jan 2017 18:50:23 +0100
Subject: [PATCH 1/3] jfs: atomically read inode size

See i_size_read() comments in include/linux/fs.h

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
---
 fs/jfs/resize.c | 4 ++--
 fs/jfs/super.c  | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/jfs/resize.c b/fs/jfs/resize.c
index bd9b641ada2c..7ddcb445a3d9 100644
--- a/fs/jfs/resize.c
+++ b/fs/jfs/resize.c
@@ -98,7 +98,7 @@ int jfs_extendfs(struct super_block *sb, s64 newLVSize, int newLogSize)
 		goto out;
 	}
 
-	VolumeSize = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
+	VolumeSize = i_size_read(sb->s_bdev->bd_inode) >> sb->s_blocksize_bits;
 
 	if (VolumeSize) {
 		if (newLVSize > VolumeSize) {
@@ -211,7 +211,7 @@ int jfs_extendfs(struct super_block *sb, s64 newLVSize, int newLogSize)
 	txQuiesce(sb);
 
 	/* Reset size of direct inode */
-	sbi->direct_inode->i_size =  sb->s_bdev->bd_inode->i_size;
+	sbi->direct_inode->i_size =  i_size_read(sb->s_bdev->bd_inode);
 
 	if (sbi->mntflag & JFS_INLINELOG) {
 		/*
diff --git a/fs/jfs/super.c b/fs/jfs/super.c
index 2be7c9ce6663..51881eb8ccff 100644
--- a/fs/jfs/super.c
+++ b/fs/jfs/super.c
@@ -283,7 +283,7 @@ static int parse_options(char *options, struct super_block *sb, s64 *newLVSize,
 		}
 		case Opt_resize_nosize:
 		{
-			*newLVSize = sb->s_bdev->bd_inode->i_size >>
+			*newLVSize = i_size_read(sb->s_bdev->bd_inode) >>
 				sb->s_blocksize_bits;
 			if (*newLVSize == 0)
 				pr_err("JFS: Cannot determine volume size\n");
@@ -549,7 +549,7 @@ static int jfs_fill_super(struct super_block *sb, void *data, int silent)
 		goto out_unload;
 	}
 	inode->i_ino = 0;
-	inode->i_size = sb->s_bdev->bd_inode->i_size;
+	inode->i_size = i_size_read(sb->s_bdev->bd_inode);
 	inode->i_mapping->a_ops = &jfs_metapage_aops;
 	hlist_add_fake(&inode->i_hash);
 	mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);

From 9bcf66c72d726322441ec82962994e69157613e4 Mon Sep 17 00:00:00 2001
From: Jan Kara <jack@suse.cz>
Date: Thu, 22 Jun 2017 15:31:10 +0200
Subject: [PATCH 2/3] jfs: Don't clear SGID when inheriting ACLs

When new directory 'DIR1' is created in a directory 'DIR0' with SGID bit
set, DIR1 is expected to have SGID bit set (and owning group equal to
the owning group of 'DIR0'). However when 'DIR0' also has some default
ACLs that 'DIR1' inherits, setting these ACLs will result in SGID bit on
'DIR1' to get cleared if user is not member of the owning group.

Fix the problem by moving posix_acl_update_mode() out of
__jfs_set_acl() into jfs_set_acl(). That way the function will not be
called when inheriting ACLs which is what we want as it prevents SGID
bit clearing and the mode has been properly set by posix_acl_create()
anyway.

Fixes: 073931017b49d9458aa351605b43a7e34598caef
CC: stable@vger.kernel.org
CC: jfs-discussion@lists.sourceforge.net
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
---
 fs/jfs/acl.c | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/fs/jfs/acl.c b/fs/jfs/acl.c
index 7bc186f4ed4d..1be45c8d460d 100644
--- a/fs/jfs/acl.c
+++ b/fs/jfs/acl.c
@@ -77,13 +77,6 @@ static int __jfs_set_acl(tid_t tid, struct inode *inode, int type,
 	switch (type) {
 	case ACL_TYPE_ACCESS:
 		ea_name = XATTR_NAME_POSIX_ACL_ACCESS;
-		if (acl) {
-			rc = posix_acl_update_mode(inode, &inode->i_mode, &acl);
-			if (rc)
-				return rc;
-			inode->i_ctime = current_time(inode);
-			mark_inode_dirty(inode);
-		}
 		break;
 	case ACL_TYPE_DEFAULT:
 		ea_name = XATTR_NAME_POSIX_ACL_DEFAULT;
@@ -118,9 +111,17 @@ int jfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 
 	tid = txBegin(inode->i_sb, 0);
 	mutex_lock(&JFS_IP(inode)->commit_mutex);
+	if (type == ACL_TYPE_ACCESS && acl) {
+		rc = posix_acl_update_mode(inode, &inode->i_mode, &acl);
+		if (rc)
+			goto end_tx;
+		inode->i_ctime = current_time(inode);
+		mark_inode_dirty(inode);
+	}
 	rc = __jfs_set_acl(tid, inode, type, acl);
 	if (!rc)
 		rc = txCommit(tid, 1, &inode, 0);
+end_tx:
 	txEnd(tid);
 	mutex_unlock(&JFS_IP(inode)->commit_mutex);
 	return rc;

From f070e5ac9bc7de71c34402048ce5526dccbd347c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ernesto=20A=2E=20Fern=C3=A1ndez?=
 <ernesto.mnd.fernandez@gmail.com>
Date: Wed, 12 Jul 2017 06:55:35 -0300
Subject: [PATCH 3/3] jfs: preserve i_mode if __jfs_set_acl() fails
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

When changing a file's acl mask, __jfs_set_acl() will first set the group
bits of i_mode to the value of the mask, and only then set the actual
extended attribute representing the new acl.

If the second part fails (due to lack of space, for example) and the file
had no acl attribute to begin with, the system will from now on assume
that the mask permission bits are actual group permission bits, potentially
granting access to the wrong users.

Prevent this by only changing the inode mode after the acl has been set.

Signed-off-by: Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
---
 fs/jfs/acl.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/fs/jfs/acl.c b/fs/jfs/acl.c
index 1be45c8d460d..2e71b6e7e646 100644
--- a/fs/jfs/acl.c
+++ b/fs/jfs/acl.c
@@ -108,19 +108,26 @@ int jfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 {
 	int rc;
 	tid_t tid;
+	int update_mode = 0;
+	umode_t mode = inode->i_mode;
 
 	tid = txBegin(inode->i_sb, 0);
 	mutex_lock(&JFS_IP(inode)->commit_mutex);
 	if (type == ACL_TYPE_ACCESS && acl) {
-		rc = posix_acl_update_mode(inode, &inode->i_mode, &acl);
+		rc = posix_acl_update_mode(inode, &mode, &acl);
 		if (rc)
 			goto end_tx;
-		inode->i_ctime = current_time(inode);
-		mark_inode_dirty(inode);
+		update_mode = 1;
 	}
 	rc = __jfs_set_acl(tid, inode, type, acl);
-	if (!rc)
+	if (!rc) {
+		if (update_mode) {
+			inode->i_mode = mode;
+			inode->i_ctime = current_time(inode);
+			mark_inode_dirty(inode);
+		}
 		rc = txCommit(tid, 1, &inode, 0);
+	}
 end_tx:
 	txEnd(tid);
 	mutex_unlock(&JFS_IP(inode)->commit_mutex);