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-rw-r--r--fs/namei.c239
1 files changed, 137 insertions, 102 deletions
diff --git a/fs/namei.c b/fs/namei.c
index 471eb9fead6e..32351c045bae 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -204,6 +204,14 @@ getname_flags(const char __user *filename, int flags, int *empty)
}
struct filename *
+getname_uflags(const char __user *filename, int uflags)
+{
+ int flags = (uflags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0;
+
+ return getname_flags(filename, flags, NULL);
+}
+
+struct filename *
getname(const char __user * filename)
{
return getname_flags(filename, 0, NULL);
@@ -247,6 +255,9 @@ getname_kernel(const char * filename)
void putname(struct filename *name)
{
+ if (IS_ERR_OR_NULL(name))
+ return;
+
BUG_ON(name->refcnt <= 0);
if (--name->refcnt > 0)
@@ -2456,7 +2467,7 @@ static int path_lookupat(struct nameidata *nd, unsigned flags, struct path *path
return err;
}
-int filename_lookup(int dfd, struct filename *name, unsigned flags,
+static int __filename_lookup(int dfd, struct filename *name, unsigned flags,
struct path *path, struct path *root)
{
int retval;
@@ -2474,6 +2485,14 @@ int filename_lookup(int dfd, struct filename *name, unsigned flags,
audit_inode(name, path->dentry,
flags & LOOKUP_MOUNTPOINT ? AUDIT_INODE_NOEVAL : 0);
restore_nameidata();
+ return retval;
+}
+
+int filename_lookup(int dfd, struct filename *name, unsigned flags,
+ struct path *path, struct path *root)
+{
+ int retval = __filename_lookup(dfd, name, flags, path, root);
+
putname(name);
return retval;
}
@@ -2495,7 +2514,7 @@ static int path_parentat(struct nameidata *nd, unsigned flags,
return err;
}
-static struct filename *filename_parentat(int dfd, struct filename *name,
+static int __filename_parentat(int dfd, struct filename *name,
unsigned int flags, struct path *parent,
struct qstr *last, int *type)
{
@@ -2503,7 +2522,7 @@ static struct filename *filename_parentat(int dfd, struct filename *name,
struct nameidata nd;
if (IS_ERR(name))
- return name;
+ return PTR_ERR(name);
set_nameidata(&nd, dfd, name, NULL);
retval = path_parentat(&nd, flags | LOOKUP_RCU, parent);
if (unlikely(retval == -ECHILD))
@@ -2514,29 +2533,34 @@ static struct filename *filename_parentat(int dfd, struct filename *name,
*last = nd.last;
*type = nd.last_type;
audit_inode(name, parent->dentry, AUDIT_INODE_PARENT);
- } else {
- putname(name);
- name = ERR_PTR(retval);
}
restore_nameidata();
- return name;
+ return retval;
+}
+
+static int filename_parentat(int dfd, struct filename *name,
+ unsigned int flags, struct path *parent,
+ struct qstr *last, int *type)
+{
+ int retval = __filename_parentat(dfd, name, flags, parent, last, type);
+
+ putname(name);
+ return retval;
}
/* does lookup, returns the object with parent locked */
struct dentry *kern_path_locked(const char *name, struct path *path)
{
- struct filename *filename;
struct dentry *d;
struct qstr last;
- int type;
+ int type, error;
- filename = filename_parentat(AT_FDCWD, getname_kernel(name), 0, path,
+ error = filename_parentat(AT_FDCWD, getname_kernel(name), 0, path,
&last, &type);
- if (IS_ERR(filename))
- return ERR_CAST(filename);
+ if (error)
+ return ERR_PTR(error);
if (unlikely(type != LAST_NORM)) {
path_put(path);
- putname(filename);
return ERR_PTR(-EINVAL);
}
inode_lock_nested(path->dentry->d_inode, I_MUTEX_PARENT);
@@ -2545,7 +2569,6 @@ struct dentry *kern_path_locked(const char *name, struct path *path)
inode_unlock(path->dentry->d_inode);
path_put(path);
}
- putname(filename);
return d;
}
@@ -3564,7 +3587,7 @@ struct file *do_file_open_root(const struct path *root,
return file;
}
-static struct dentry *filename_create(int dfd, struct filename *name,
+static struct dentry *__filename_create(int dfd, struct filename *name,
struct path *path, unsigned int lookup_flags)
{
struct dentry *dentry = ERR_PTR(-EEXIST);
@@ -3580,9 +3603,9 @@ static struct dentry *filename_create(int dfd, struct filename *name,
*/
lookup_flags &= LOOKUP_REVAL;
- name = filename_parentat(dfd, name, lookup_flags, path, &last, &type);
- if (IS_ERR(name))
- return ERR_CAST(name);
+ error = __filename_parentat(dfd, name, lookup_flags, path, &last, &type);
+ if (error)
+ return ERR_PTR(error);
/*
* Yucky last component or no last component at all?
@@ -3620,7 +3643,6 @@ static struct dentry *filename_create(int dfd, struct filename *name,
error = err2;
goto fail;
}
- putname(name);
return dentry;
fail:
dput(dentry);
@@ -3631,10 +3653,18 @@ unlock:
mnt_drop_write(path->mnt);
out:
path_put(path);
- putname(name);
return dentry;
}
+static inline struct dentry *filename_create(int dfd, struct filename *name,
+ struct path *path, unsigned int lookup_flags)
+{
+ struct dentry *res = __filename_create(dfd, name, path, lookup_flags);
+
+ putname(name);
+ return res;
+}
+
struct dentry *kern_path_create(int dfd, const char *pathname,
struct path *path, unsigned int lookup_flags)
{
@@ -3723,7 +3753,7 @@ static int may_mknod(umode_t mode)
}
}
-static long do_mknodat(int dfd, const char __user *filename, umode_t mode,
+static int do_mknodat(int dfd, struct filename *name, umode_t mode,
unsigned int dev)
{
struct user_namespace *mnt_userns;
@@ -3734,17 +3764,18 @@ static long do_mknodat(int dfd, const char __user *filename, umode_t mode,
error = may_mknod(mode);
if (error)
- return error;
+ goto out1;
retry:
- dentry = user_path_create(dfd, filename, &path, lookup_flags);
+ dentry = __filename_create(dfd, name, &path, lookup_flags);
+ error = PTR_ERR(dentry);
if (IS_ERR(dentry))
- return PTR_ERR(dentry);
+ goto out1;
if (!IS_POSIXACL(path.dentry->d_inode))
mode &= ~current_umask();
error = security_path_mknod(&path, dentry, mode, dev);
if (error)
- goto out;
+ goto out2;
mnt_userns = mnt_user_ns(path.mnt);
switch (mode & S_IFMT) {
@@ -3763,24 +3794,26 @@ retry:
dentry, mode, 0);
break;
}
-out:
+out2:
done_path_create(&path, dentry);
if (retry_estale(error, lookup_flags)) {
lookup_flags |= LOOKUP_REVAL;
goto retry;
}
+out1:
+ putname(name);
return error;
}
SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, umode_t, mode,
unsigned int, dev)
{
- return do_mknodat(dfd, filename, mode, dev);
+ return do_mknodat(dfd, getname(filename), mode, dev);
}
SYSCALL_DEFINE3(mknod, const char __user *, filename, umode_t, mode, unsigned, dev)
{
- return do_mknodat(AT_FDCWD, filename, mode, dev);
+ return do_mknodat(AT_FDCWD, getname(filename), mode, dev);
}
/**
@@ -3825,7 +3858,7 @@ int vfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
}
EXPORT_SYMBOL(vfs_mkdir);
-static long do_mkdirat(int dfd, const char __user *pathname, umode_t mode)
+int do_mkdirat(int dfd, struct filename *name, umode_t mode)
{
struct dentry *dentry;
struct path path;
@@ -3833,9 +3866,10 @@ static long do_mkdirat(int dfd, const char __user *pathname, umode_t mode)
unsigned int lookup_flags = LOOKUP_DIRECTORY;
retry:
- dentry = user_path_create(dfd, pathname, &path, lookup_flags);
+ dentry = __filename_create(dfd, name, &path, lookup_flags);
+ error = PTR_ERR(dentry);
if (IS_ERR(dentry))
- return PTR_ERR(dentry);
+ goto out_putname;
if (!IS_POSIXACL(path.dentry->d_inode))
mode &= ~current_umask();
@@ -3851,17 +3885,19 @@ retry:
lookup_flags |= LOOKUP_REVAL;
goto retry;
}
+out_putname:
+ putname(name);
return error;
}
SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, umode_t, mode)
{
- return do_mkdirat(dfd, pathname, mode);
+ return do_mkdirat(dfd, getname(pathname), mode);
}
SYSCALL_DEFINE2(mkdir, const char __user *, pathname, umode_t, mode)
{
- return do_mkdirat(AT_FDCWD, pathname, mode);
+ return do_mkdirat(AT_FDCWD, getname(pathname), mode);
}
/**
@@ -3919,62 +3955,62 @@ out:
}
EXPORT_SYMBOL(vfs_rmdir);
-long do_rmdir(int dfd, struct filename *name)
+int do_rmdir(int dfd, struct filename *name)
{
struct user_namespace *mnt_userns;
- int error = 0;
+ int error;
struct dentry *dentry;
struct path path;
struct qstr last;
int type;
unsigned int lookup_flags = 0;
retry:
- name = filename_parentat(dfd, name, lookup_flags,
- &path, &last, &type);
- if (IS_ERR(name))
- return PTR_ERR(name);
+ error = __filename_parentat(dfd, name, lookup_flags, &path, &last, &type);
+ if (error)
+ goto exit1;
switch (type) {
case LAST_DOTDOT:
error = -ENOTEMPTY;
- goto exit1;
+ goto exit2;
case LAST_DOT:
error = -EINVAL;
- goto exit1;
+ goto exit2;
case LAST_ROOT:
error = -EBUSY;
- goto exit1;
+ goto exit2;
}
error = mnt_want_write(path.mnt);
if (error)
- goto exit1;
+ goto exit2;
inode_lock_nested(path.dentry->d_inode, I_MUTEX_PARENT);
dentry = __lookup_hash(&last, path.dentry, lookup_flags);
error = PTR_ERR(dentry);
if (IS_ERR(dentry))
- goto exit2;
+ goto exit3;
if (!dentry->d_inode) {
error = -ENOENT;
- goto exit3;
+ goto exit4;
}
error = security_path_rmdir(&path, dentry);
if (error)
- goto exit3;
+ goto exit4;
mnt_userns = mnt_user_ns(path.mnt);
error = vfs_rmdir(mnt_userns, path.dentry->d_inode, dentry);
-exit3:
+exit4:
dput(dentry);
-exit2:
+exit3:
inode_unlock(path.dentry->d_inode);
mnt_drop_write(path.mnt);
-exit1:
+exit2:
path_put(&path);
if (retry_estale(error, lookup_flags)) {
lookup_flags |= LOOKUP_REVAL;
goto retry;
}
+exit1:
putname(name);
return error;
}
@@ -4057,7 +4093,7 @@ EXPORT_SYMBOL(vfs_unlink);
* writeout happening, and we don't want to prevent access to the directory
* while waiting on the I/O.
*/
-long do_unlinkat(int dfd, struct filename *name)
+int do_unlinkat(int dfd, struct filename *name)
{
int error;
struct dentry *dentry;
@@ -4068,17 +4104,17 @@ long do_unlinkat(int dfd, struct filename *name)
struct inode *delegated_inode = NULL;
unsigned int lookup_flags = 0;
retry:
- name = filename_parentat(dfd, name, lookup_flags, &path, &last, &type);
- if (IS_ERR(name))
- return PTR_ERR(name);
+ error = __filename_parentat(dfd, name, lookup_flags, &path, &last, &type);
+ if (error)
+ goto exit1;
error = -EISDIR;
if (type != LAST_NORM)
- goto exit1;
+ goto exit2;
error = mnt_want_write(path.mnt);
if (error)
- goto exit1;
+ goto exit2;
retry_deleg:
inode_lock_nested(path.dentry->d_inode, I_MUTEX_PARENT);
dentry = __lookup_hash(&last, path.dentry, lookup_flags);
@@ -4095,11 +4131,11 @@ retry_deleg:
ihold(inode);
error = security_path_unlink(&path, dentry);
if (error)
- goto exit2;
+ goto exit3;
mnt_userns = mnt_user_ns(path.mnt);
error = vfs_unlink(mnt_userns, path.dentry->d_inode, dentry,
&delegated_inode);
-exit2:
+exit3:
dput(dentry);
}
inode_unlock(path.dentry->d_inode);
@@ -4112,13 +4148,14 @@ exit2:
goto retry_deleg;
}
mnt_drop_write(path.mnt);
-exit1:
+exit2:
path_put(&path);
if (retry_estale(error, lookup_flags)) {
lookup_flags |= LOOKUP_REVAL;
inode = NULL;
goto retry;
}
+exit1:
putname(name);
return error;
@@ -4129,7 +4166,7 @@ slashes:
error = -EISDIR;
else
error = -ENOTDIR;
- goto exit2;
+ goto exit3;
}
SYSCALL_DEFINE3(unlinkat, int, dfd, const char __user *, pathname, int, flag)
@@ -4184,23 +4221,22 @@ int vfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
}
EXPORT_SYMBOL(vfs_symlink);
-static long do_symlinkat(const char __user *oldname, int newdfd,
- const char __user *newname)
+int do_symlinkat(struct filename *from, int newdfd, struct filename *to)
{
int error;
- struct filename *from;
struct dentry *dentry;
struct path path;
unsigned int lookup_flags = 0;
- from = getname(oldname);
- if (IS_ERR(from))
- return PTR_ERR(from);
+ if (IS_ERR(from)) {
+ error = PTR_ERR(from);
+ goto out_putnames;
+ }
retry:
- dentry = user_path_create(newdfd, newname, &path, lookup_flags);
+ dentry = __filename_create(newdfd, to, &path, lookup_flags);
error = PTR_ERR(dentry);
if (IS_ERR(dentry))
- goto out_putname;
+ goto out_putnames;
error = security_path_symlink(&path, dentry, from->name);
if (!error) {
@@ -4215,7 +4251,8 @@ retry:
lookup_flags |= LOOKUP_REVAL;
goto retry;
}
-out_putname:
+out_putnames:
+ putname(to);
putname(from);
return error;
}
@@ -4223,12 +4260,12 @@ out_putname:
SYSCALL_DEFINE3(symlinkat, const char __user *, oldname,
int, newdfd, const char __user *, newname)
{
- return do_symlinkat(oldname, newdfd, newname);
+ return do_symlinkat(getname(oldname), newdfd, getname(newname));
}
SYSCALL_DEFINE2(symlink, const char __user *, oldname, const char __user *, newname)
{
- return do_symlinkat(oldname, AT_FDCWD, newname);
+ return do_symlinkat(getname(oldname), AT_FDCWD, getname(newname));
}
/**
@@ -4329,8 +4366,8 @@ EXPORT_SYMBOL(vfs_link);
* with linux 2.0, and to avoid hard-linking to directories
* and other special files. --ADM
*/
-static int do_linkat(int olddfd, const char __user *oldname, int newdfd,
- const char __user *newname, int flags)
+int do_linkat(int olddfd, struct filename *old, int newdfd,
+ struct filename *new, int flags)
{
struct user_namespace *mnt_userns;
struct dentry *new_dentry;
@@ -4339,31 +4376,32 @@ static int do_linkat(int olddfd, const char __user *oldname, int newdfd,
int how = 0;
int error;
- if ((flags & ~(AT_SYMLINK_FOLLOW | AT_EMPTY_PATH)) != 0)
- return -EINVAL;
+ if ((flags & ~(AT_SYMLINK_FOLLOW | AT_EMPTY_PATH)) != 0) {
+ error = -EINVAL;
+ goto out_putnames;
+ }
/*
* To use null names we require CAP_DAC_READ_SEARCH
* This ensures that not everyone will be able to create
* handlink using the passed filedescriptor.
*/
- if (flags & AT_EMPTY_PATH) {
- if (!capable(CAP_DAC_READ_SEARCH))
- return -ENOENT;
- how = LOOKUP_EMPTY;
+ if (flags & AT_EMPTY_PATH && !capable(CAP_DAC_READ_SEARCH)) {
+ error = -ENOENT;
+ goto out_putnames;
}
if (flags & AT_SYMLINK_FOLLOW)
how |= LOOKUP_FOLLOW;
retry:
- error = user_path_at(olddfd, oldname, how, &old_path);
+ error = __filename_lookup(olddfd, old, how, &old_path, NULL);
if (error)
- return error;
+ goto out_putnames;
- new_dentry = user_path_create(newdfd, newname, &new_path,
+ new_dentry = __filename_create(newdfd, new, &new_path,
(how & LOOKUP_REVAL));
error = PTR_ERR(new_dentry);
if (IS_ERR(new_dentry))
- goto out;
+ goto out_putpath;
error = -EXDEV;
if (old_path.mnt != new_path.mnt)
@@ -4391,8 +4429,11 @@ out_dput:
how |= LOOKUP_REVAL;
goto retry;
}
-out:
+out_putpath:
path_put(&old_path);
+out_putnames:
+ putname(old);
+ putname(new);
return error;
}
@@ -4400,12 +4441,13 @@ out:
SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname,
int, newdfd, const char __user *, newname, int, flags)
{
- return do_linkat(olddfd, oldname, newdfd, newname, flags);
+ return do_linkat(olddfd, getname_uflags(oldname, flags),
+ newdfd, getname(newname), flags);
}
SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname)
{
- return do_linkat(AT_FDCWD, oldname, AT_FDCWD, newname, 0);
+ return do_linkat(AT_FDCWD, getname(oldname), AT_FDCWD, getname(newname), 0);
}
/**
@@ -4600,29 +4642,25 @@ int do_renameat2(int olddfd, struct filename *from, int newdfd,
int error = -EINVAL;
if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
- goto put_both;
+ goto put_names;
if ((flags & (RENAME_NOREPLACE | RENAME_WHITEOUT)) &&
(flags & RENAME_EXCHANGE))
- goto put_both;
+ goto put_names;
if (flags & RENAME_EXCHANGE)
target_flags = 0;
retry:
- from = filename_parentat(olddfd, from, lookup_flags, &old_path,
+ error = __filename_parentat(olddfd, from, lookup_flags, &old_path,
&old_last, &old_type);
- if (IS_ERR(from)) {
- error = PTR_ERR(from);
- goto put_new;
- }
+ if (error)
+ goto put_names;
- to = filename_parentat(newdfd, to, lookup_flags, &new_path, &new_last,
+ error = __filename_parentat(newdfd, to, lookup_flags, &new_path, &new_last,
&new_type);
- if (IS_ERR(to)) {
- error = PTR_ERR(to);
+ if (error)
goto exit1;
- }
error = -EXDEV;
if (old_path.mnt != new_path.mnt)
@@ -4725,12 +4763,9 @@ exit1:
lookup_flags |= LOOKUP_REVAL;
goto retry;
}
-put_both:
- if (!IS_ERR(from))
- putname(from);
-put_new:
- if (!IS_ERR(to))
- putname(to);
+put_names:
+ putname(from);
+ putname(to);
return error;
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-29 23:23:15 +0000