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Diffstat (limited to 'fs/statfs.c')
-rw-r--r--fs/statfs.c206
1 files changed, 102 insertions, 104 deletions
diff --git a/fs/statfs.c b/fs/statfs.c
index 30ea8c8a996..083dc0ac914 100644
--- a/fs/statfs.c
+++ b/fs/statfs.c
@@ -1,5 +1,5 @@
#include <linux/syscalls.h>
-#include <linux/module.h>
+#include <linux/export.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/mount.h>
@@ -7,6 +7,7 @@
#include <linux/statfs.h>
#include <linux/security.h>
#include <linux/uaccess.h>
+#include "internal.h"
static int flags_by_mnt(int mnt_flags)
{
@@ -45,7 +46,7 @@ static int calculate_f_flags(struct vfsmount *mnt)
flags_by_sb(mnt->mnt_sb->s_flags);
}
-int statfs_by_dentry(struct dentry *dentry, struct kstatfs *buf)
+static int statfs_by_dentry(struct dentry *dentry, struct kstatfs *buf)
{
int retval;
@@ -73,165 +74,162 @@ int vfs_statfs(struct path *path, struct kstatfs *buf)
}
EXPORT_SYMBOL(vfs_statfs);
-static int do_statfs_native(struct path *path, struct statfs *buf)
+int user_statfs(const char __user *pathname, struct kstatfs *st)
{
- struct kstatfs st;
- int retval;
+ struct path path;
+ int error;
+ unsigned int lookup_flags = LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT;
+retry:
+ error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path);
+ if (!error) {
+ error = vfs_statfs(&path, st);
+ path_put(&path);
+ if (retry_estale(error, lookup_flags)) {
+ lookup_flags |= LOOKUP_REVAL;
+ goto retry;
+ }
+ }
+ return error;
+}
- retval = vfs_statfs(path, &st);
- if (retval)
- return retval;
+int fd_statfs(int fd, struct kstatfs *st)
+{
+ struct fd f = fdget_raw(fd);
+ int error = -EBADF;
+ if (f.file) {
+ error = vfs_statfs(&f.file->f_path, st);
+ fdput(f);
+ }
+ return error;
+}
+
+static int do_statfs_native(struct kstatfs *st, struct statfs __user *p)
+{
+ struct statfs buf;
- if (sizeof(*buf) == sizeof(st))
- memcpy(buf, &st, sizeof(st));
+ if (sizeof(buf) == sizeof(*st))
+ memcpy(&buf, st, sizeof(*st));
else {
- if (sizeof buf->f_blocks == 4) {
- if ((st.f_blocks | st.f_bfree | st.f_bavail |
- st.f_bsize | st.f_frsize) &
+ if (sizeof buf.f_blocks == 4) {
+ if ((st->f_blocks | st->f_bfree | st->f_bavail |
+ st->f_bsize | st->f_frsize) &
0xffffffff00000000ULL)
return -EOVERFLOW;
/*
* f_files and f_ffree may be -1; it's okay to stuff
* that into 32 bits
*/
- if (st.f_files != -1 &&
- (st.f_files & 0xffffffff00000000ULL))
+ if (st->f_files != -1 &&
+ (st->f_files & 0xffffffff00000000ULL))
return -EOVERFLOW;
- if (st.f_ffree != -1 &&
- (st.f_ffree & 0xffffffff00000000ULL))
+ if (st->f_ffree != -1 &&
+ (st->f_ffree & 0xffffffff00000000ULL))
return -EOVERFLOW;
}
- buf->f_type = st.f_type;
- buf->f_bsize = st.f_bsize;
- buf->f_blocks = st.f_blocks;
- buf->f_bfree = st.f_bfree;
- buf->f_bavail = st.f_bavail;
- buf->f_files = st.f_files;
- buf->f_ffree = st.f_ffree;
- buf->f_fsid = st.f_fsid;
- buf->f_namelen = st.f_namelen;
- buf->f_frsize = st.f_frsize;
- buf->f_flags = st.f_flags;
- memset(buf->f_spare, 0, sizeof(buf->f_spare));
+ buf.f_type = st->f_type;
+ buf.f_bsize = st->f_bsize;
+ buf.f_blocks = st->f_blocks;
+ buf.f_bfree = st->f_bfree;
+ buf.f_bavail = st->f_bavail;
+ buf.f_files = st->f_files;
+ buf.f_ffree = st->f_ffree;
+ buf.f_fsid = st->f_fsid;
+ buf.f_namelen = st->f_namelen;
+ buf.f_frsize = st->f_frsize;
+ buf.f_flags = st->f_flags;
+ memset(buf.f_spare, 0, sizeof(buf.f_spare));
}
+ if (copy_to_user(p, &buf, sizeof(buf)))
+ return -EFAULT;
return 0;
}
-static int do_statfs64(struct path *path, struct statfs64 *buf)
+static int do_statfs64(struct kstatfs *st, struct statfs64 __user *p)
{
- struct kstatfs st;
- int retval;
-
- retval = vfs_statfs(path, &st);
- if (retval)
- return retval;
-
- if (sizeof(*buf) == sizeof(st))
- memcpy(buf, &st, sizeof(st));
+ struct statfs64 buf;
+ if (sizeof(buf) == sizeof(*st))
+ memcpy(&buf, st, sizeof(*st));
else {
- buf->f_type = st.f_type;
- buf->f_bsize = st.f_bsize;
- buf->f_blocks = st.f_blocks;
- buf->f_bfree = st.f_bfree;
- buf->f_bavail = st.f_bavail;
- buf->f_files = st.f_files;
- buf->f_ffree = st.f_ffree;
- buf->f_fsid = st.f_fsid;
- buf->f_namelen = st.f_namelen;
- buf->f_frsize = st.f_frsize;
- buf->f_flags = st.f_flags;
- memset(buf->f_spare, 0, sizeof(buf->f_spare));
+ buf.f_type = st->f_type;
+ buf.f_bsize = st->f_bsize;
+ buf.f_blocks = st->f_blocks;
+ buf.f_bfree = st->f_bfree;
+ buf.f_bavail = st->f_bavail;
+ buf.f_files = st->f_files;
+ buf.f_ffree = st->f_ffree;
+ buf.f_fsid = st->f_fsid;
+ buf.f_namelen = st->f_namelen;
+ buf.f_frsize = st->f_frsize;
+ buf.f_flags = st->f_flags;
+ memset(buf.f_spare, 0, sizeof(buf.f_spare));
}
+ if (copy_to_user(p, &buf, sizeof(buf)))
+ return -EFAULT;
return 0;
}
SYSCALL_DEFINE2(statfs, const char __user *, pathname, struct statfs __user *, buf)
{
- struct path path;
- int error;
-
- error = user_path(pathname, &path);
- if (!error) {
- struct statfs tmp;
- error = do_statfs_native(&path, &tmp);
- if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
- error = -EFAULT;
- path_put(&path);
- }
+ struct kstatfs st;
+ int error = user_statfs(pathname, &st);
+ if (!error)
+ error = do_statfs_native(&st, buf);
return error;
}
SYSCALL_DEFINE3(statfs64, const char __user *, pathname, size_t, sz, struct statfs64 __user *, buf)
{
- struct path path;
- long error;
-
+ struct kstatfs st;
+ int error;
if (sz != sizeof(*buf))
return -EINVAL;
- error = user_path(pathname, &path);
- if (!error) {
- struct statfs64 tmp;
- error = do_statfs64(&path, &tmp);
- if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
- error = -EFAULT;
- path_put(&path);
- }
+ error = user_statfs(pathname, &st);
+ if (!error)
+ error = do_statfs64(&st, buf);
return error;
}
SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct statfs __user *, buf)
{
- struct file *file;
- struct statfs tmp;
- int error;
-
- error = -EBADF;
- file = fget(fd);
- if (!file)
- goto out;
- error = do_statfs_native(&file->f_path, &tmp);
- if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
- error = -EFAULT;
- fput(file);
-out:
+ struct kstatfs st;
+ int error = fd_statfs(fd, &st);
+ if (!error)
+ error = do_statfs_native(&st, buf);
return error;
}
SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, size_t, sz, struct statfs64 __user *, buf)
{
- struct file *file;
- struct statfs64 tmp;
+ struct kstatfs st;
int error;
if (sz != sizeof(*buf))
return -EINVAL;
- error = -EBADF;
- file = fget(fd);
- if (!file)
- goto out;
- error = do_statfs64(&file->f_path, &tmp);
- if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
- error = -EFAULT;
- fput(file);
-out:
+ error = fd_statfs(fd, &st);
+ if (!error)
+ error = do_statfs64(&st, buf);
return error;
}
-SYSCALL_DEFINE2(ustat, unsigned, dev, struct ustat __user *, ubuf)
+int vfs_ustat(dev_t dev, struct kstatfs *sbuf)
{
- struct super_block *s;
- struct ustat tmp;
- struct kstatfs sbuf;
+ struct super_block *s = user_get_super(dev);
int err;
-
- s = user_get_super(new_decode_dev(dev));
if (!s)
return -EINVAL;
- err = statfs_by_dentry(s->s_root, &sbuf);
+ err = statfs_by_dentry(s->s_root, sbuf);
drop_super(s);
+ return err;
+}
+
+SYSCALL_DEFINE2(ustat, unsigned, dev, struct ustat __user *, ubuf)
+{
+ struct ustat tmp;
+ struct kstatfs sbuf;
+ int err = vfs_ustat(new_decode_dev(dev), &sbuf);
if (err)
return err;
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 16:28:49 +0000