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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-02 20:25:04 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-02 20:25:04 -0700
commitaab174f0df5d72d31caccf281af5f614fa254578 (patch)
tree2a172c5009c4ac8755e858593154c258ce7709a0 /fs/open.c
parentca41cc96b2813221b05af57d0355157924de5a07 (diff)
parent2bd2c1941f141ad780135ccc1cd08ca71a24f10a (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs update from Al Viro: - big one - consolidation of descriptor-related logics; almost all of that is moved to fs/file.c (BTW, I'm seriously tempted to rename the result to fd.c. As it is, we have a situation when file_table.c is about handling of struct file and file.c is about handling of descriptor tables; the reasons are historical - file_table.c used to be about a static array of struct file we used to have way back). A lot of stray ends got cleaned up and converted to saner primitives, disgusting mess in android/binder.c is still disgusting, but at least doesn't poke so much in descriptor table guts anymore. A bunch of relatively minor races got fixed in process, plus an ext4 struct file leak. - related thing - fget_light() partially unuglified; see fdget() in there (and yes, it generates the code as good as we used to have). - also related - bits of Cyrill's procfs stuff that got entangled into that work; _not_ all of it, just the initial move to fs/proc/fd.c and switch of fdinfo to seq_file. - Alex's fs/coredump.c spiltoff - the same story, had been easier to take that commit than mess with conflicts. The rest is a separate pile, this was just a mechanical code movement. - a few misc patches all over the place. Not all for this cycle, there'll be more (and quite a few currently sit in akpm's tree)." Fix up trivial conflicts in the android binder driver, and some fairly simple conflicts due to two different changes to the sock_alloc_file() interface ("take descriptor handling from sock_alloc_file() to callers" vs "net: Providing protocol type via system.sockprotoname xattr of /proc/PID/fd entries" adding a dentry name to the socket) * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (72 commits) MAX_LFS_FILESIZE should be a loff_t compat: fs: Generic compat_sys_sendfile implementation fs: push rcu_barrier() from deactivate_locked_super() to filesystems btrfs: reada_extent doesn't need kref for refcount coredump: move core dump functionality into its own file coredump: prevent double-free on an error path in core dumper usb/gadget: fix misannotations fcntl: fix misannotations ceph: don't abuse d_delete() on failure exits hypfs: ->d_parent is never NULL or negative vfs: delete surplus inode NULL check switch simple cases of fget_light to fdget new helpers: fdget()/fdput() switch o2hb_region_dev_write() to fget_light() proc_map_files_readdir(): don't bother with grabbing files make get_file() return its argument vhost_set_vring(): turn pollstart/pollstop into bool switch prctl_set_mm_exe_file() to fget_light() switch xfs_find_handle() to fget_light() switch xfs_swapext() to fget_light() ...
Diffstat (limited to 'fs/open.c')
-rw-r--r--fs/open.c130
1 files changed, 30 insertions, 100 deletions
diff --git a/fs/open.c b/fs/open.c
index b0bae3a4182..44da0feeca2 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -132,27 +132,27 @@ SYSCALL_DEFINE2(truncate, const char __user *, path, long, length)
static long do_sys_ftruncate(unsigned int fd, loff_t length, int small)
{
- struct inode * inode;
+ struct inode *inode;
struct dentry *dentry;
- struct file * file;
+ struct fd f;
int error;
error = -EINVAL;
if (length < 0)
goto out;
error = -EBADF;
- file = fget(fd);
- if (!file)
+ f = fdget(fd);
+ if (!f.file)
goto out;
/* explicitly opened as large or we are on 64-bit box */
- if (file->f_flags & O_LARGEFILE)
+ if (f.file->f_flags & O_LARGEFILE)
small = 0;
- dentry = file->f_path.dentry;
+ dentry = f.file->f_path.dentry;
inode = dentry->d_inode;
error = -EINVAL;
- if (!S_ISREG(inode->i_mode) || !(file->f_mode & FMODE_WRITE))
+ if (!S_ISREG(inode->i_mode) || !(f.file->f_mode & FMODE_WRITE))
goto out_putf;
error = -EINVAL;
@@ -165,14 +165,14 @@ static long do_sys_ftruncate(unsigned int fd, loff_t length, int small)
goto out_putf;
sb_start_write(inode->i_sb);
- error = locks_verify_truncate(inode, file, length);
+ error = locks_verify_truncate(inode, f.file, length);
if (!error)
- error = security_path_truncate(&file->f_path);
+ error = security_path_truncate(&f.file->f_path);
if (!error)
- error = do_truncate(dentry, length, ATTR_MTIME|ATTR_CTIME, file);
+ error = do_truncate(dentry, length, ATTR_MTIME|ATTR_CTIME, f.file);
sb_end_write(inode->i_sb);
out_putf:
- fput(file);
+ fdput(f);
out:
return error;
}
@@ -276,15 +276,13 @@ int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
SYSCALL_DEFINE(fallocate)(int fd, int mode, loff_t offset, loff_t len)
{
- struct file *file;
+ struct fd f = fdget(fd);
int error = -EBADF;
- file = fget(fd);
- if (file) {
- error = do_fallocate(file, mode, offset, len);
- fput(file);
+ if (f.file) {
+ error = do_fallocate(f.file, mode, offset, len);
+ fdput(f);
}
-
return error;
}
@@ -400,16 +398,15 @@ out:
SYSCALL_DEFINE1(fchdir, unsigned int, fd)
{
- struct file *file;
+ struct fd f = fdget_raw(fd);
struct inode *inode;
- int error, fput_needed;
+ int error = -EBADF;
error = -EBADF;
- file = fget_raw_light(fd, &fput_needed);
- if (!file)
+ if (!f.file)
goto out;
- inode = file->f_path.dentry->d_inode;
+ inode = f.file->f_path.dentry->d_inode;
error = -ENOTDIR;
if (!S_ISDIR(inode->i_mode))
@@ -417,9 +414,9 @@ SYSCALL_DEFINE1(fchdir, unsigned int, fd)
error = inode_permission(inode, MAY_EXEC | MAY_CHDIR);
if (!error)
- set_fs_pwd(current->fs, &file->f_path);
+ set_fs_pwd(current->fs, &f.file->f_path);
out_putf:
- fput_light(file, fput_needed);
+ fdput(f);
out:
return error;
}
@@ -582,23 +579,20 @@ SYSCALL_DEFINE3(lchown, const char __user *, filename, uid_t, user, gid_t, group
SYSCALL_DEFINE3(fchown, unsigned int, fd, uid_t, user, gid_t, group)
{
- struct file * file;
+ struct fd f = fdget(fd);
int error = -EBADF;
- struct dentry * dentry;
- file = fget(fd);
- if (!file)
+ if (!f.file)
goto out;
- error = mnt_want_write_file(file);
+ error = mnt_want_write_file(f.file);
if (error)
goto out_fput;
- dentry = file->f_path.dentry;
- audit_inode(NULL, dentry);
- error = chown_common(&file->f_path, user, group);
- mnt_drop_write_file(file);
+ audit_inode(NULL, f.file->f_path.dentry);
+ error = chown_common(&f.file->f_path, user, group);
+ mnt_drop_write_file(f.file);
out_fput:
- fput(file);
+ fdput(f);
out:
return error;
}
@@ -803,50 +797,6 @@ struct file *dentry_open(const struct path *path, int flags,
}
EXPORT_SYMBOL(dentry_open);
-static void __put_unused_fd(struct files_struct *files, unsigned int fd)
-{
- struct fdtable *fdt = files_fdtable(files);
- __clear_open_fd(fd, fdt);
- if (fd < files->next_fd)
- files->next_fd = fd;
-}
-
-void put_unused_fd(unsigned int fd)
-{
- struct files_struct *files = current->files;
- spin_lock(&files->file_lock);
- __put_unused_fd(files, fd);
- spin_unlock(&files->file_lock);
-}
-
-EXPORT_SYMBOL(put_unused_fd);
-
-/*
- * Install a file pointer in the fd array.
- *
- * The VFS is full of places where we drop the files lock between
- * setting the open_fds bitmap and installing the file in the file
- * array. At any such point, we are vulnerable to a dup2() race
- * installing a file in the array before us. We need to detect this and
- * fput() the struct file we are about to overwrite in this case.
- *
- * It should never happen - if we allow dup2() do it, _really_ bad things
- * will follow.
- */
-
-void fd_install(unsigned int fd, struct file *file)
-{
- struct files_struct *files = current->files;
- struct fdtable *fdt;
- spin_lock(&files->file_lock);
- fdt = files_fdtable(files);
- BUG_ON(fdt->fd[fd] != NULL);
- rcu_assign_pointer(fdt->fd[fd], file);
- spin_unlock(&files->file_lock);
-}
-
-EXPORT_SYMBOL(fd_install);
-
static inline int build_open_flags(int flags, umode_t mode, struct open_flags *op)
{
int lookup_flags = 0;
@@ -858,7 +808,7 @@ static inline int build_open_flags(int flags, umode_t mode, struct open_flags *o
op->mode = 0;
/* Must never be set by userspace */
- flags &= ~FMODE_NONOTIFY;
+ flags &= ~FMODE_NONOTIFY & ~O_CLOEXEC;
/*
* O_SYNC is implemented as __O_SYNC|O_DSYNC. As many places only
@@ -1038,23 +988,7 @@ EXPORT_SYMBOL(filp_close);
*/
SYSCALL_DEFINE1(close, unsigned int, fd)
{
- struct file * filp;
- struct files_struct *files = current->files;
- struct fdtable *fdt;
- int retval;
-
- spin_lock(&files->file_lock);
- fdt = files_fdtable(files);
- if (fd >= fdt->max_fds)
- goto out_unlock;
- filp = fdt->fd[fd];
- if (!filp)
- goto out_unlock;
- rcu_assign_pointer(fdt->fd[fd], NULL);
- __clear_close_on_exec(fd, fdt);
- __put_unused_fd(files, fd);
- spin_unlock(&files->file_lock);
- retval = filp_close(filp, files);
+ int retval = __close_fd(current->files, fd);
/* can't restart close syscall because file table entry was cleared */
if (unlikely(retval == -ERESTARTSYS ||
@@ -1064,10 +998,6 @@ SYSCALL_DEFINE1(close, unsigned int, fd)
retval = -EINTR;
return retval;
-
-out_unlock:
- spin_unlock(&files->file_lock);
- return -EBADF;
}
EXPORT_SYMBOL(sys_close);