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authorLinus Torvalds2011-07-18 09:03:15 -0700
committerLinus Torvalds2011-07-18 09:03:15 -0700
commitd36c30181c4cf6ead34ae30fa2c777b871225c87 (patch)
tree8a2476c0eb6bb83ed5a8b493d79458d0e114a146
parenta406721dff91a9a5297d140dbb90327966cf9bc0 (diff)
parent0916a5e45fbd2604a303c8cc18e6b2b7c815e4c9 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: hppfs_lookup(): don't open-code lookup_one_len() hppfs: fix dentry leak cramfs: get_cramfs_inode() returns ERR_PTR() on failure ufs should use d_splice_alias() fix exofs ->get_parent() ceph analog of cifs build_path_from_dentry() race fix cifs: build_path_from_dentry() race fix
-rw-r--r--fs/ceph/mds_client.c19
-rw-r--r--fs/cifs/dir.c13
-rw-r--r--fs/cramfs/inode.c22
-rw-r--r--fs/exofs/super.c2
-rw-r--r--fs/hppfs/hppfs.c31
-rw-r--r--fs/ufs/namei.c12
6 files changed, 54 insertions, 45 deletions
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 79743d146be6..0c1d91756528 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -1438,12 +1438,15 @@ char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
struct dentry *temp;
char *path;
int len, pos;
+ unsigned seq;
if (dentry == NULL)
return ERR_PTR(-EINVAL);
retry:
len = 0;
+ seq = read_seqbegin(&rename_lock);
+ rcu_read_lock();
for (temp = dentry; !IS_ROOT(temp);) {
struct inode *inode = temp->d_inode;
if (inode && ceph_snap(inode) == CEPH_SNAPDIR)
@@ -1455,10 +1458,12 @@ retry:
len += 1 + temp->d_name.len;
temp = temp->d_parent;
if (temp == NULL) {
+ rcu_read_unlock();
pr_err("build_path corrupt dentry %p\n", dentry);
return ERR_PTR(-EINVAL);
}
}
+ rcu_read_unlock();
if (len)
len--; /* no leading '/' */
@@ -1467,9 +1472,12 @@ retry:
return ERR_PTR(-ENOMEM);
pos = len;
path[pos] = 0; /* trailing null */
+ rcu_read_lock();
for (temp = dentry; !IS_ROOT(temp) && pos != 0; ) {
- struct inode *inode = temp->d_inode;
+ struct inode *inode;
+ spin_lock(&temp->d_lock);
+ inode = temp->d_inode;
if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
dout("build_path path+%d: %p SNAPDIR\n",
pos, temp);
@@ -1478,21 +1486,26 @@ retry:
break;
} else {
pos -= temp->d_name.len;
- if (pos < 0)
+ if (pos < 0) {
+ spin_unlock(&temp->d_lock);
break;
+ }
strncpy(path + pos, temp->d_name.name,
temp->d_name.len);
}
+ spin_unlock(&temp->d_lock);
if (pos)
path[--pos] = '/';
temp = temp->d_parent;
if (temp == NULL) {
+ rcu_read_unlock();
pr_err("build_path corrupt dentry\n");
kfree(path);
return ERR_PTR(-EINVAL);
}
}
- if (pos != 0) {
+ rcu_read_unlock();
+ if (pos != 0 || read_seqretry(&rename_lock, seq)) {
pr_err("build_path did not end path lookup where "
"expected, namelen is %d, pos is %d\n", len, pos);
/* presumably this is only possible if racing with a
diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
index 81914df47ef1..fa8c21d913bc 100644
--- a/fs/cifs/dir.c
+++ b/fs/cifs/dir.c
@@ -55,6 +55,7 @@ build_path_from_dentry(struct dentry *direntry)
char dirsep;
struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
+ unsigned seq;
if (direntry == NULL)
return NULL; /* not much we can do if dentry is freed and
@@ -68,22 +69,29 @@ build_path_from_dentry(struct dentry *direntry)
dfsplen = 0;
cifs_bp_rename_retry:
namelen = dfsplen;
+ seq = read_seqbegin(&rename_lock);
+ rcu_read_lock();
for (temp = direntry; !IS_ROOT(temp);) {
namelen += (1 + temp->d_name.len);
temp = temp->d_parent;
if (temp == NULL) {
cERROR(1, "corrupt dentry");
+ rcu_read_unlock();
return NULL;
}
}
+ rcu_read_unlock();
full_path = kmalloc(namelen+1, GFP_KERNEL);
if (full_path == NULL)
return full_path;
full_path[namelen] = 0; /* trailing null */
+ rcu_read_lock();
for (temp = direntry; !IS_ROOT(temp);) {
+ spin_lock(&temp->d_lock);
namelen -= 1 + temp->d_name.len;
if (namelen < 0) {
+ spin_unlock(&temp->d_lock);
break;
} else {
full_path[namelen] = dirsep;
@@ -91,14 +99,17 @@ cifs_bp_rename_retry:
temp->d_name.len);
cFYI(0, "name: %s", full_path + namelen);
}
+ spin_unlock(&temp->d_lock);
temp = temp->d_parent;
if (temp == NULL) {
cERROR(1, "corrupt dentry");
+ rcu_read_unlock();
kfree(full_path);
return NULL;
}
}
- if (namelen != dfsplen) {
+ rcu_read_unlock();
+ if (namelen != dfsplen || read_seqretry(&rename_lock, seq)) {
cERROR(1, "did not end path lookup where expected namelen is %d",
namelen);
/* presumably this is only possible if racing with a rename
diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c
index e141939080f0..739fb59bcdc2 100644
--- a/fs/cramfs/inode.c
+++ b/fs/cramfs/inode.c
@@ -37,7 +37,7 @@ static DEFINE_MUTEX(read_mutex);
/* These macros may change in future, to provide better st_ino semantics. */
#define OFFSET(x) ((x)->i_ino)
-static unsigned long cramino(struct cramfs_inode *cino, unsigned int offset)
+static unsigned long cramino(const struct cramfs_inode *cino, unsigned int offset)
{
if (!cino->offset)
return offset + 1;
@@ -61,7 +61,7 @@ static unsigned long cramino(struct cramfs_inode *cino, unsigned int offset)
}
static struct inode *get_cramfs_inode(struct super_block *sb,
- struct cramfs_inode *cramfs_inode, unsigned int offset)
+ const struct cramfs_inode *cramfs_inode, unsigned int offset)
{
struct inode *inode;
static struct timespec zerotime;
@@ -317,7 +317,7 @@ static int cramfs_fill_super(struct super_block *sb, void *data, int silent)
/* Set it all up.. */
sb->s_op = &cramfs_ops;
root = get_cramfs_inode(sb, &super.root, 0);
- if (!root)
+ if (IS_ERR(root))
goto out;
sb->s_root = d_alloc_root(root);
if (!sb->s_root) {
@@ -423,6 +423,7 @@ static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
{
unsigned int offset = 0;
+ struct inode *inode = NULL;
int sorted;
mutex_lock(&read_mutex);
@@ -449,8 +450,8 @@ static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, s
for (;;) {
if (!namelen) {
- mutex_unlock(&read_mutex);
- return ERR_PTR(-EIO);
+ inode = ERR_PTR(-EIO);
+ goto out;
}
if (name[namelen-1])
break;
@@ -462,17 +463,18 @@ static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, s
if (retval > 0)
continue;
if (!retval) {
- struct cramfs_inode entry = *de;
- mutex_unlock(&read_mutex);
- d_add(dentry, get_cramfs_inode(dir->i_sb, &entry, dir_off));
- return NULL;
+ inode = get_cramfs_inode(dir->i_sb, de, dir_off);
+ break;
}
/* else (retval < 0) */
if (sorted)
break;
}
+out:
mutex_unlock(&read_mutex);
- d_add(dentry, NULL);
+ if (IS_ERR(inode))
+ return ERR_CAST(inode);
+ d_add(dentry, inode);
return NULL;
}
diff --git a/fs/exofs/super.c b/fs/exofs/super.c
index 06065bd37fc3..c57beddcc217 100644
--- a/fs/exofs/super.c
+++ b/fs/exofs/super.c
@@ -913,7 +913,7 @@ struct dentry *exofs_get_parent(struct dentry *child)
unsigned long ino = exofs_parent_ino(child);
if (!ino)
- return NULL;
+ return ERR_PTR(-ESTALE);
return d_obtain_alias(exofs_iget(child->d_inode->i_sb, ino));
}
diff --git a/fs/hppfs/hppfs.c b/fs/hppfs/hppfs.c
index 87ed48e0343d..85c098a499f3 100644
--- a/fs/hppfs/hppfs.c
+++ b/fs/hppfs/hppfs.c
@@ -139,7 +139,8 @@ static int file_removed(struct dentry *dentry, const char *file)
static struct dentry *hppfs_lookup(struct inode *ino, struct dentry *dentry,
struct nameidata *nd)
{
- struct dentry *proc_dentry, *new, *parent;
+ struct dentry *proc_dentry, *parent;
+ struct qstr *name = &dentry->d_name;
struct inode *inode;
int err, deleted;
@@ -149,23 +150,9 @@ static struct dentry *hppfs_lookup(struct inode *ino, struct dentry *dentry,
else if (deleted)
return ERR_PTR(-ENOENT);
- err = -ENOMEM;
parent = HPPFS_I(ino)->proc_dentry;
mutex_lock(&parent->d_inode->i_mutex);
- proc_dentry = d_lookup(parent, &dentry->d_name);
- if (proc_dentry == NULL) {
- proc_dentry = d_alloc(parent, &dentry->d_name);
- if (proc_dentry == NULL) {
- mutex_unlock(&parent->d_inode->i_mutex);
- goto out;
- }
- new = (*parent->d_inode->i_op->lookup)(parent->d_inode,
- proc_dentry, NULL);
- if (new) {
- dput(proc_dentry);
- proc_dentry = new;
- }
- }
+ proc_dentry = lookup_one_len(name->name, parent, name->len);
mutex_unlock(&parent->d_inode->i_mutex);
if (IS_ERR(proc_dentry))
@@ -174,13 +161,11 @@ static struct dentry *hppfs_lookup(struct inode *ino, struct dentry *dentry,
err = -ENOMEM;
inode = get_inode(ino->i_sb, proc_dentry);
if (!inode)
- goto out_dput;
+ goto out;
d_add(dentry, inode);
return NULL;
- out_dput:
- dput(proc_dentry);
out:
return ERR_PTR(err);
}
@@ -690,8 +675,10 @@ static struct inode *get_inode(struct super_block *sb, struct dentry *dentry)
struct inode *proc_ino = dentry->d_inode;
struct inode *inode = new_inode(sb);
- if (!inode)
+ if (!inode) {
+ dput(dentry);
return ERR_PTR(-ENOMEM);
+ }
if (S_ISDIR(dentry->d_inode->i_mode)) {
inode->i_op = &hppfs_dir_iops;
@@ -704,7 +691,7 @@ static struct inode *get_inode(struct super_block *sb, struct dentry *dentry)
inode->i_fop = &hppfs_file_fops;
}
- HPPFS_I(inode)->proc_dentry = dget(dentry);
+ HPPFS_I(inode)->proc_dentry = dentry;
inode->i_uid = proc_ino->i_uid;
inode->i_gid = proc_ino->i_gid;
@@ -737,7 +724,7 @@ static int hppfs_fill_super(struct super_block *sb, void *d, int silent)
sb->s_fs_info = proc_mnt;
err = -ENOMEM;
- root_inode = get_inode(sb, proc_mnt->mnt_sb->s_root);
+ root_inode = get_inode(sb, dget(proc_mnt->mnt_sb->s_root));
if (!root_inode)
goto out_mntput;
diff --git a/fs/ufs/namei.c b/fs/ufs/namei.c
index 29309e25417f..b57aab9a1184 100644
--- a/fs/ufs/namei.c
+++ b/fs/ufs/namei.c
@@ -56,16 +56,12 @@ static struct dentry *ufs_lookup(struct inode * dir, struct dentry *dentry, stru
lock_ufs(dir->i_sb);
ino = ufs_inode_by_name(dir, &dentry->d_name);
- if (ino) {
+ if (ino)
inode = ufs_iget(dir->i_sb, ino);
- if (IS_ERR(inode)) {
- unlock_ufs(dir->i_sb);
- return ERR_CAST(inode);
- }
- }
unlock_ufs(dir->i_sb);
- d_add(dentry, inode);
- return NULL;
+ if (IS_ERR(inode))
+ return ERR_CAST(inode);
+ return d_splice_alias(inode, dentry);
}
/*