linux-kernel - [PATCH 2/2] fs/9p: We should not allocate a new inode when creating hardlinks.

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-prev] [day] [month] [year] [list]

Date:	Thu,  5 Jan 2012 13:39:50 +0530
From:	"Aneesh Kumar K.V" <aneesh.kumar@...ux.vnet.ibm.com>
To:	v9fs-developer@...ts.sourceforge.net
Cc:	linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
	"Aneesh Kumar K.V" <aneesh.kumar@...ux.vnet.ibm.com>
Subject: [PATCH 2/2] fs/9p: We should not allocate a new inode when creating hardlinks.

From: "Aneesh Kumar K.V" <aneesh.kumar@...ux.vnet.ibm.com>

Don't do new_inode_from fid in case of hardlink creation. This ensures
that link count for hardlink files get updated properly. Earlier link count
was not updated on removing a hardlink with cache mode enabled.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@...ux.vnet.ibm.com>
---
 fs/9p/vfs_inode.c |   43 ++++++++++++++++++++++++-------------------
 1 files changed, 24 insertions(+), 19 deletions(-)

diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index c330776..5dd0c46 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -678,26 +678,31 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
 		goto error;
 	}
 
-	/* now walk from the parent so we can get unopened fid */
-	fid = p9_client_walk(dfid, 1, &name, 1);
-	if (IS_ERR(fid)) {
-		err = PTR_ERR(fid);
-		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
-		fid = NULL;
-		goto error;
-	}
-
-	/* instantiate inode and assign the unopened fid to the dentry */
-	inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
-	if (IS_ERR(inode)) {
-		err = PTR_ERR(inode);
-		P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n", err);
-		goto error;
+	if (!(perm & P9_DMLINK)) {
+		/* now walk from the parent so we can get unopened fid */
+		fid = p9_client_walk(dfid, 1, &name, 1);
+		if (IS_ERR(fid)) {
+			err = PTR_ERR(fid);
+			P9_DPRINTK(P9_DEBUG_VFS,
+				   "p9_client_walk failed %d\n", err);
+			fid = NULL;
+			goto error;
+		}
+		/*
+		 * instantiate inode and assign the unopened fid to the dentry
+		 */
+		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
+		if (IS_ERR(inode)) {
+			err = PTR_ERR(inode);
+			P9_DPRINTK(P9_DEBUG_VFS,
+				   "inode creation failed %d\n", err);
+			goto error;
+		}
+		err = v9fs_fid_add(dentry, fid);
+		if (err < 0)
+			goto error;
+		d_instantiate(dentry, inode);
 	}
-	err = v9fs_fid_add(dentry, fid);
-	if (err < 0)
-		goto error;
-	d_instantiate(dentry, inode);
 	return ofid;
 error:
 	if (ofid)
-- 
1.7.8.1.362.g5d6df

--
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/