Commit 60606eca authored by Al Viro's avatar Al Viro
Browse files

ocfs2_inode_lock_update(): make sure we don't change the type bits of i_mode 



... even if another node has gone insane.  Fail with -ESTALE if it detects
an attempt to change the type bits.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent e89f00d6

fs/ocfs2/dlmglue.c

+10 −2
Original line number Diff line number Diff line
@@ -2204,7 +2204,7 @@ static void ocfs2_unpack_timespec(struct timespec64 *spec, 
	spec->tv_nsec = packed_time & OCFS2_NSEC_MASK;

}



static void ocfs2_refresh_inode_from_lvb(struct inode *inode)

static int ocfs2_refresh_inode_from_lvb(struct inode *inode)

{

	struct ocfs2_inode_info *oi = OCFS2_I(inode);

	struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres;
@@ -2213,6 +2213,8 @@ static void ocfs2_refresh_inode_from_lvb(struct inode *inode) 
	mlog_meta_lvb(0, lockres);



	lvb = ocfs2_dlm_lvb(&lockres->l_lksb);

	if (inode_wrong_type(inode, be16_to_cpu(lvb->lvb_imode)))

		return -ESTALE;



	/* We're safe here without the lockres lock... */

	spin_lock(&oi->ip_lock);
@@ -2240,6 +2242,7 @@ static void ocfs2_refresh_inode_from_lvb(struct inode *inode) 
	ocfs2_unpack_timespec(&inode->i_ctime,

			      be64_to_cpu(lvb->lvb_ictime_packed));

	spin_unlock(&oi->ip_lock);

	return 0;

}



static inline int ocfs2_meta_lvb_is_trustable(struct inode *inode,
@@ -2342,7 +2345,8 @@ static int ocfs2_inode_lock_update(struct inode *inode, 
	if (ocfs2_meta_lvb_is_trustable(inode, lockres)) {

		mlog(0, "Trusting LVB on inode %llu\n",

		     (unsigned long long)oi->ip_blkno);

		ocfs2_refresh_inode_from_lvb(inode);

		status = ocfs2_refresh_inode_from_lvb(inode);

		goto bail_refresh;

	} else {

		/* Boo, we have to go to disk. */

		/* read bh, cast, ocfs2_refresh_inode */
@@ -2352,6 +2356,10 @@ static int ocfs2_inode_lock_update(struct inode *inode, 
			goto bail_refresh;

		}

		fe = (struct ocfs2_dinode *) (*bh)->b_data;

		if (inode_wrong_type(inode, le16_to_cpu(fe->i_mode))) {

			status = -ESTALE;

			goto bail_refresh;

		}



		/* This is a good chance to make sure we're not

		 * locking an invalid object.  ocfs2_read_inode_block()