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Diffstat (limited to 'fs/open.c')
-rw-r--r--fs/open.c130
1 files changed, 46 insertions, 84 deletions
diff --git a/fs/open.c b/fs/open.c
index d0e955b558ad..0285ce7dbd51 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -68,7 +68,6 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
long vfs_truncate(const struct path *path, loff_t length)
{
struct inode *inode;
- struct dentry *upperdentry;
long error;
inode = path->dentry->d_inode;
@@ -91,17 +90,7 @@ long vfs_truncate(const struct path *path, loff_t length)
if (IS_APPEND(inode))
goto mnt_drop_write_and_out;
- /*
- * If this is an overlayfs then do as if opening the file so we get
- * write access on the upper inode, not on the overlay inode. For
- * non-overlay filesystems d_real() is an identity function.
- */
- upperdentry = d_real(path->dentry, NULL, O_WRONLY, 0);
- error = PTR_ERR(upperdentry);
- if (IS_ERR(upperdentry))
- goto mnt_drop_write_and_out;
-
- error = get_write_access(upperdentry->d_inode);
+ error = get_write_access(inode);
if (error)
goto mnt_drop_write_and_out;
@@ -120,7 +109,7 @@ long vfs_truncate(const struct path *path, loff_t length)
error = do_truncate(path->dentry, length, 0, NULL);
put_write_and_out:
- put_write_access(upperdentry->d_inode);
+ put_write_access(inode);
mnt_drop_write_and_out:
mnt_drop_write(path->mnt);
out:
@@ -707,12 +696,12 @@ int ksys_fchown(unsigned int fd, uid_t user, gid_t group)
if (!f.file)
goto out;
- error = mnt_want_write_file_path(f.file);
+ error = mnt_want_write_file(f.file);
if (error)
goto out_fput;
audit_file(f.file);
error = chown_common(&f.file->f_path, user, group);
- mnt_drop_write_file_path(f.file);
+ mnt_drop_write_file(f.file);
out_fput:
fdput(f);
out:
@@ -724,27 +713,13 @@ SYSCALL_DEFINE3(fchown, unsigned int, fd, uid_t, user, gid_t, group)
return ksys_fchown(fd, user, group);
}
-int open_check_o_direct(struct file *f)
-{
- /* NB: we're sure to have correct a_ops only after f_op->open */
- if (f->f_flags & O_DIRECT) {
- if (!f->f_mapping->a_ops || !f->f_mapping->a_ops->direct_IO)
- return -EINVAL;
- }
- return 0;
-}
-
static int do_dentry_open(struct file *f,
struct inode *inode,
- int (*open)(struct inode *, struct file *),
- const struct cred *cred)
+ int (*open)(struct inode *, struct file *))
{
static const struct file_operations empty_fops = {};
int error;
- f->f_mode = OPEN_FMODE(f->f_flags) | FMODE_LSEEK |
- FMODE_PREAD | FMODE_PWRITE;
-
path_get(&f->f_path);
f->f_inode = inode;
f->f_mapping = inode->i_mapping;
@@ -753,7 +728,7 @@ static int do_dentry_open(struct file *f,
f->f_wb_err = filemap_sample_wb_err(f->f_mapping);
if (unlikely(f->f_flags & O_PATH)) {
- f->f_mode = FMODE_PATH;
+ f->f_mode = FMODE_PATH | FMODE_OPENED;
f->f_op = &empty_fops;
return 0;
}
@@ -780,7 +755,7 @@ static int do_dentry_open(struct file *f,
goto cleanup_all;
}
- error = security_file_open(f, cred);
+ error = security_file_open(f);
if (error)
goto cleanup_all;
@@ -788,6 +763,8 @@ static int do_dentry_open(struct file *f,
if (error)
goto cleanup_all;
+ /* normally all 3 are set; ->open() can clear them if needed */
+ f->f_mode |= FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE;
if (!open)
open = f->f_op->open;
if (open) {
@@ -795,6 +772,7 @@ static int do_dentry_open(struct file *f,
if (error)
goto cleanup_all;
}
+ f->f_mode |= FMODE_OPENED;
if ((f->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)
i_readcount_inc(inode);
if ((f->f_mode & FMODE_READ) &&
@@ -809,9 +787,16 @@ static int do_dentry_open(struct file *f,
file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping);
+ /* NB: we're sure to have correct a_ops only after f_op->open */
+ if (f->f_flags & O_DIRECT) {
+ if (!f->f_mapping->a_ops || !f->f_mapping->a_ops->direct_IO)
+ return -EINVAL;
+ }
return 0;
cleanup_all:
+ if (WARN_ON_ONCE(error > 0))
+ error = -EINVAL;
fops_put(f->f_op);
if (f->f_mode & FMODE_WRITER) {
put_write_access(inode);
@@ -847,19 +832,12 @@ cleanup_file:
* Returns zero on success or -errno if the open failed.
*/
int finish_open(struct file *file, struct dentry *dentry,
- int (*open)(struct inode *, struct file *),
- int *opened)
+ int (*open)(struct inode *, struct file *))
{
- int error;
- BUG_ON(*opened & FILE_OPENED); /* once it's opened, it's opened */
+ BUG_ON(file->f_mode & FMODE_OPENED); /* once it's opened, it's opened */
file->f_path.dentry = dentry;
- error = do_dentry_open(file, d_backing_inode(dentry), open,
- current_cred());
- if (!error)
- *opened |= FILE_OPENED;
-
- return error;
+ return do_dentry_open(file, d_backing_inode(dentry), open);
}
EXPORT_SYMBOL(finish_open);
@@ -874,13 +852,13 @@ EXPORT_SYMBOL(finish_open);
* NB: unlike finish_open() this function does consume the dentry reference and
* the caller need not dput() it.
*
- * Returns "1" which must be the return value of ->atomic_open() after having
+ * Returns "0" which must be the return value of ->atomic_open() after having
* called this function.
*/
int finish_no_open(struct file *file, struct dentry *dentry)
{
file->f_path.dentry = dentry;
- return 1;
+ return 0;
}
EXPORT_SYMBOL(finish_no_open);
@@ -896,16 +874,10 @@ EXPORT_SYMBOL(file_path);
* @file: newly allocated file with f_flag initialized
* @cred: credentials to use
*/
-int vfs_open(const struct path *path, struct file *file,
- const struct cred *cred)
+int vfs_open(const struct path *path, struct file *file)
{
- struct dentry *dentry = d_real(path->dentry, NULL, file->f_flags, 0);
-
- if (IS_ERR(dentry))
- return PTR_ERR(dentry);
-
file->f_path = *path;
- return do_dentry_open(file, d_backing_inode(dentry), NULL, cred);
+ return do_dentry_open(file, d_backing_inode(path->dentry), NULL);
}
struct file *dentry_open(const struct path *path, int flags,
@@ -919,19 +891,11 @@ struct file *dentry_open(const struct path *path, int flags,
/* We must always pass in a valid mount pointer. */
BUG_ON(!path->mnt);
- f = get_empty_filp();
+ f = alloc_empty_file(flags, cred);
if (!IS_ERR(f)) {
- f->f_flags = flags;
- error = vfs_open(path, f, cred);
- if (!error) {
- /* from now on we need fput() to dispose of f */
- error = open_check_o_direct(f);
- if (error) {
- fput(f);
- f = ERR_PTR(error);
- }
- } else {
- put_filp(f);
+ error = vfs_open(path, f);
+ if (error) {
+ fput(f);
f = ERR_PTR(error);
}
}
@@ -939,6 +903,24 @@ struct file *dentry_open(const struct path *path, int flags,
}
EXPORT_SYMBOL(dentry_open);
+struct file *open_with_fake_path(const struct path *path, int flags,
+ struct inode *inode, const struct cred *cred)
+{
+ struct file *f = alloc_empty_file_noaccount(flags, cred);
+ if (!IS_ERR(f)) {
+ int error;
+
+ f->f_path = *path;
+ error = do_dentry_open(f, inode, NULL);
+ if (error) {
+ fput(f);
+ f = ERR_PTR(error);
+ }
+ }
+ return f;
+}
+EXPORT_SYMBOL(open_with_fake_path);
+
static inline int build_open_flags(int flags, umode_t mode, struct open_flags *op)
{
int lookup_flags = 0;
@@ -1063,26 +1045,6 @@ struct file *file_open_root(struct dentry *dentry, struct vfsmount *mnt,
}
EXPORT_SYMBOL(file_open_root);
-struct file *filp_clone_open(struct file *oldfile)
-{
- struct file *file;
- int retval;
-
- file = get_empty_filp();
- if (IS_ERR(file))
- return file;
-
- file->f_flags = oldfile->f_flags;
- retval = vfs_open(&oldfile->f_path, file, oldfile->f_cred);
- if (retval) {
- put_filp(file);
- return ERR_PTR(retval);
- }
-
- return file;
-}
-EXPORT_SYMBOL(filp_clone_open);
-
long do_sys_open(int dfd, const char __user *filename, int flags, umode_t mode)
{
struct open_flags op;