aboutsummaryrefslogtreecommitdiffstats
path: root/fs
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2017-07-05 13:13:32 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-07-05 13:13:32 -0700
commit3bad2f1c676581d01e7645eb03e9b27e28b0a92e (patch)
tree7e946eb2c7dab8c08e473ee1249be9a814728158 /fs
parentCavium CNN55XX: fix broken default Kconfig entry (diff)
parentSwitch flock copyin/copyout primitives to copy_{from,to}_user() (diff)
downloadlinux-dev-3bad2f1c676581d01e7645eb03e9b27e28b0a92e.tar.xz
linux-dev-3bad2f1c676581d01e7645eb03e9b27e28b0a92e.zip
Merge branch 'work.misc-set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc user access cleanups from Al Viro: "The first pile is assorted getting rid of cargo-culted access_ok(), cargo-culted set_fs() and field-by-field copyouts. The same description applies to a lot of stuff in other branches - this is just the stuff that didn't fit into a more specific topical branch" * 'work.misc-set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: Switch flock copyin/copyout primitives to copy_{from,to}_user() fs/fcntl: return -ESRCH in f_setown when pid/pgid can't be found fs/fcntl: f_setown, avoid undefined behaviour fs/fcntl: f_setown, allow returning error lpfc debugfs: get rid of pointless access_ok() adb: get rid of pointless access_ok() isdn: get rid of pointless access_ok() compat statfs: switch to copy_to_user() fs/locks: don't mess with the address limit in compat_fcntl64 nfsd_readlink(): switch to vfs_get_link() drbd: ->sendpage() never needed set_fs() fs/locks: pass kernel struct flock to fcntl_getlk/setlk fs: locks: Fix some troubles at kernel-doc comments
Diffstat (limited to 'fs')
-rw-r--r--fs/fcntl.c231
-rw-r--r--fs/locks.c97
-rw-r--r--fs/nfsd/vfs.c39
-rw-r--r--fs/statfs.c58
4 files changed, 214 insertions, 211 deletions
diff --git a/fs/fcntl.c b/fs/fcntl.c
index ed051f825bad..b6bd89628025 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -109,20 +109,34 @@ void __f_setown(struct file *filp, struct pid *pid, enum pid_type type,
}
EXPORT_SYMBOL(__f_setown);
-void f_setown(struct file *filp, unsigned long arg, int force)
+int f_setown(struct file *filp, unsigned long arg, int force)
{
enum pid_type type;
- struct pid *pid;
- int who = arg;
+ struct pid *pid = NULL;
+ int who = arg, ret = 0;
+
type = PIDTYPE_PID;
if (who < 0) {
+ /* avoid overflow below */
+ if (who == INT_MIN)
+ return -EINVAL;
+
type = PIDTYPE_PGID;
who = -who;
}
+
rcu_read_lock();
- pid = find_vpid(who);
- __f_setown(filp, pid, type, force);
+ if (who) {
+ pid = find_vpid(who);
+ if (!pid)
+ ret = -ESRCH;
+ }
+
+ if (!ret)
+ __f_setown(filp, pid, type, force);
rcu_read_unlock();
+
+ return ret;
}
EXPORT_SYMBOL(f_setown);
@@ -307,6 +321,8 @@ static long fcntl_rw_hint(struct file *file, unsigned int cmd,
static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
struct file *filp)
{
+ void __user *argp = (void __user *)arg;
+ struct flock flock;
long err = -EINVAL;
switch (cmd) {
@@ -334,7 +350,11 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
case F_OFD_GETLK:
#endif
case F_GETLK:
- err = fcntl_getlk(filp, cmd, (struct flock __user *) arg);
+ if (copy_from_user(&flock, argp, sizeof(flock)))
+ return -EFAULT;
+ err = fcntl_getlk(filp, cmd, &flock);
+ if (!err && copy_to_user(argp, &flock, sizeof(flock)))
+ return -EFAULT;
break;
#if BITS_PER_LONG != 32
/* 32-bit arches must use fcntl64() */
@@ -344,7 +364,9 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
/* Fallthrough */
case F_SETLK:
case F_SETLKW:
- err = fcntl_setlk(fd, filp, cmd, (struct flock __user *) arg);
+ if (copy_from_user(&flock, argp, sizeof(flock)))
+ return -EFAULT;
+ err = fcntl_setlk(fd, filp, cmd, &flock);
break;
case F_GETOWN:
/*
@@ -358,8 +380,7 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
force_successful_syscall_return();
break;
case F_SETOWN:
- f_setown(filp, arg, 1);
- err = 0;
+ err = f_setown(filp, arg, 1);
break;
case F_GETOWN_EX:
err = f_getown_ex(filp, arg);
@@ -450,7 +471,9 @@ out:
SYSCALL_DEFINE3(fcntl64, unsigned int, fd, unsigned int, cmd,
unsigned long, arg)
{
+ void __user *argp = (void __user *)arg;
struct fd f = fdget_raw(fd);
+ struct flock64 flock;
long err = -EBADF;
if (!f.file)
@@ -468,14 +491,21 @@ SYSCALL_DEFINE3(fcntl64, unsigned int, fd, unsigned int, cmd,
switch (cmd) {
case F_GETLK64:
case F_OFD_GETLK:
- err = fcntl_getlk64(f.file, cmd, (struct flock64 __user *) arg);
+ err = -EFAULT;
+ if (copy_from_user(&flock, argp, sizeof(flock)))
+ break;
+ err = fcntl_getlk64(f.file, cmd, &flock);
+ if (!err && copy_to_user(argp, &flock, sizeof(flock)))
+ err = -EFAULT;
break;
case F_SETLK64:
case F_SETLKW64:
case F_OFD_SETLK:
case F_OFD_SETLKW:
- err = fcntl_setlk64(fd, f.file, cmd,
- (struct flock64 __user *) arg);
+ err = -EFAULT;
+ if (copy_from_user(&flock, argp, sizeof(flock)))
+ break;
+ err = fcntl_setlk64(fd, f.file, cmd, &flock);
break;
default:
err = do_fcntl(fd, cmd, arg, f.file);
@@ -489,57 +519,56 @@ out:
#endif
#ifdef CONFIG_COMPAT
+/* careful - don't use anywhere else */
+#define copy_flock_fields(from, to) \
+ (to).l_type = (from).l_type; \
+ (to).l_whence = (from).l_whence; \
+ (to).l_start = (from).l_start; \
+ (to).l_len = (from).l_len; \
+ (to).l_pid = (from).l_pid;
+
static int get_compat_flock(struct flock *kfl, struct compat_flock __user *ufl)
{
- if (!access_ok(VERIFY_READ, ufl, sizeof(*ufl)) ||
- __get_user(kfl->l_type, &ufl->l_type) ||
- __get_user(kfl->l_whence, &ufl->l_whence) ||
- __get_user(kfl->l_start, &ufl->l_start) ||
- __get_user(kfl->l_len, &ufl->l_len) ||
- __get_user(kfl->l_pid, &ufl->l_pid))
+ struct compat_flock fl;
+
+ if (copy_from_user(&fl, ufl, sizeof(struct compat_flock)))
return -EFAULT;
+ copy_flock_fields(*kfl, fl);
return 0;
}
-static int put_compat_flock(struct flock *kfl, struct compat_flock __user *ufl)
+static int get_compat_flock64(struct flock *kfl, struct compat_flock64 __user *ufl)
{
- if (!access_ok(VERIFY_WRITE, ufl, sizeof(*ufl)) ||
- __put_user(kfl->l_type, &ufl->l_type) ||
- __put_user(kfl->l_whence, &ufl->l_whence) ||
- __put_user(kfl->l_start, &ufl->l_start) ||
- __put_user(kfl->l_len, &ufl->l_len) ||
- __put_user(kfl->l_pid, &ufl->l_pid))
+ struct compat_flock64 fl;
+
+ if (copy_from_user(&fl, ufl, sizeof(struct compat_flock64)))
return -EFAULT;
+ copy_flock_fields(*kfl, fl);
return 0;
}
-#ifndef HAVE_ARCH_GET_COMPAT_FLOCK64
-static int get_compat_flock64(struct flock *kfl, struct compat_flock64 __user *ufl)
+static int put_compat_flock(struct flock *kfl, struct compat_flock __user *ufl)
{
- if (!access_ok(VERIFY_READ, ufl, sizeof(*ufl)) ||
- __get_user(kfl->l_type, &ufl->l_type) ||
- __get_user(kfl->l_whence, &ufl->l_whence) ||
- __get_user(kfl->l_start, &ufl->l_start) ||
- __get_user(kfl->l_len, &ufl->l_len) ||
- __get_user(kfl->l_pid, &ufl->l_pid))
+ struct compat_flock fl;
+
+ memset(&fl, 0, sizeof(struct compat_flock));
+ copy_flock_fields(fl, *kfl);
+ if (copy_to_user(ufl, &fl, sizeof(struct compat_flock)))
return -EFAULT;
return 0;
}
-#endif
-#ifndef HAVE_ARCH_PUT_COMPAT_FLOCK64
static int put_compat_flock64(struct flock *kfl, struct compat_flock64 __user *ufl)
{
- if (!access_ok(VERIFY_WRITE, ufl, sizeof(*ufl)) ||
- __put_user(kfl->l_type, &ufl->l_type) ||
- __put_user(kfl->l_whence, &ufl->l_whence) ||
- __put_user(kfl->l_start, &ufl->l_start) ||
- __put_user(kfl->l_len, &ufl->l_len) ||
- __put_user(kfl->l_pid, &ufl->l_pid))
+ struct compat_flock64 fl;
+
+ memset(&fl, 0, sizeof(struct compat_flock64));
+ copy_flock_fields(fl, *kfl);
+ if (copy_to_user(ufl, &fl, sizeof(struct compat_flock64)))
return -EFAULT;
return 0;
}
-#endif
+#undef copy_flock_fields
static unsigned int
convert_fcntl_cmd(unsigned int cmd)
@@ -556,76 +585,92 @@ convert_fcntl_cmd(unsigned int cmd)
return cmd;
}
+/*
+ * GETLK was successful and we need to return the data, but it needs to fit in
+ * the compat structure.
+ * l_start shouldn't be too big, unless the original start + end is greater than
+ * COMPAT_OFF_T_MAX, in which case the app was asking for trouble, so we return
+ * -EOVERFLOW in that case. l_len could be too big, in which case we just
+ * truncate it, and only allow the app to see that part of the conflicting lock
+ * that might make sense to it anyway
+ */
+static int fixup_compat_flock(struct flock *flock)
+{
+ if (flock->l_start > COMPAT_OFF_T_MAX)
+ return -EOVERFLOW;
+ if (flock->l_len > COMPAT_OFF_T_MAX)
+ flock->l_len = COMPAT_OFF_T_MAX;
+ return 0;
+}
+
COMPAT_SYSCALL_DEFINE3(fcntl64, unsigned int, fd, unsigned int, cmd,
compat_ulong_t, arg)
{
- mm_segment_t old_fs;
- struct flock f;
- long ret;
- unsigned int conv_cmd;
+ struct fd f = fdget_raw(fd);
+ struct flock flock;
+ long err = -EBADF;
+
+ if (!f.file)
+ return err;
+
+ if (unlikely(f.file->f_mode & FMODE_PATH)) {
+ if (!check_fcntl_cmd(cmd))
+ goto out_put;
+ }
+
+ err = security_file_fcntl(f.file, cmd, arg);
+ if (err)
+ goto out_put;
switch (cmd) {
case F_GETLK:
+ err = get_compat_flock(&flock, compat_ptr(arg));
+ if (err)
+ break;
+ err = fcntl_getlk(f.file, convert_fcntl_cmd(cmd), &flock);
+ if (err)
+ break;
+ err = fixup_compat_flock(&flock);
+ if (err)
+ return err;
+ err = put_compat_flock(&flock, compat_ptr(arg));
+ break;
+ case F_GETLK64:
+ case F_OFD_GETLK:
+ err = get_compat_flock64(&flock, compat_ptr(arg));
+ if (err)
+ break;
+ err = fcntl_getlk(f.file, convert_fcntl_cmd(cmd), &flock);
+ if (err)
+ break;
+ err = fixup_compat_flock(&flock);
+ if (err)
+ return err;
+ err = put_compat_flock64(&flock, compat_ptr(arg));
+ break;
case F_SETLK:
case F_SETLKW:
- ret = get_compat_flock(&f, compat_ptr(arg));
- if (ret != 0)
+ err = get_compat_flock(&flock, compat_ptr(arg));
+ if (err)
break;
- old_fs = get_fs();
- set_fs(KERNEL_DS);
- ret = sys_fcntl(fd, cmd, (unsigned long)&f);
- set_fs(old_fs);
- if (cmd == F_GETLK && ret == 0) {
- /* GETLK was successful and we need to return the data...
- * but it needs to fit in the compat structure.
- * l_start shouldn't be too big, unless the original
- * start + end is greater than COMPAT_OFF_T_MAX, in which
- * case the app was asking for trouble, so we return
- * -EOVERFLOW in that case.
- * l_len could be too big, in which case we just truncate it,
- * and only allow the app to see that part of the conflicting
- * lock that might make sense to it anyway
- */
-
- if (f.l_start > COMPAT_OFF_T_MAX)
- ret = -EOVERFLOW;
- if (f.l_len > COMPAT_OFF_T_MAX)
- f.l_len = COMPAT_OFF_T_MAX;
- if (ret == 0)
- ret = put_compat_flock(&f, compat_ptr(arg));
- }
+ err = fcntl_setlk(fd, f.file, convert_fcntl_cmd(cmd), &flock);
break;
-
- case F_GETLK64:
case F_SETLK64:
case F_SETLKW64:
- case F_OFD_GETLK:
case F_OFD_SETLK:
case F_OFD_SETLKW:
- ret = get_compat_flock64(&f, compat_ptr(arg));
- if (ret != 0)
+ err = get_compat_flock64(&flock, compat_ptr(arg));
+ if (err)
break;
- old_fs = get_fs();
- set_fs(KERNEL_DS);
- conv_cmd = convert_fcntl_cmd(cmd);
- ret = sys_fcntl(fd, conv_cmd, (unsigned long)&f);
- set_fs(old_fs);
- if ((conv_cmd == F_GETLK || conv_cmd == F_OFD_GETLK) && ret == 0) {
- /* need to return lock information - see above for commentary */
- if (f.l_start > COMPAT_LOFF_T_MAX)
- ret = -EOVERFLOW;
- if (f.l_len > COMPAT_LOFF_T_MAX)
- f.l_len = COMPAT_LOFF_T_MAX;
- if (ret == 0)
- ret = put_compat_flock64(&f, compat_ptr(arg));
- }
+ err = fcntl_setlk(fd, f.file, convert_fcntl_cmd(cmd), &flock);
break;
-
default:
- ret = sys_fcntl(fd, cmd, arg);
+ err = do_fcntl(fd, cmd, arg, f.file);
break;
}
- return ret;
+out_put:
+ fdput(f);
+ return err;
}
COMPAT_SYSCALL_DEFINE3(fcntl, unsigned int, fd, unsigned int, cmd,
diff --git a/fs/locks.c b/fs/locks.c
index af2031a1fcff..afefeb4ad6de 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1858,8 +1858,8 @@ EXPORT_SYMBOL(generic_setlease);
*
* Call this to establish a lease on the file. The "lease" argument is not
* used for F_UNLCK requests and may be NULL. For commands that set or alter
- * an existing lease, the (*lease)->fl_lmops->lm_break operation must be set;
- * if not, this function will return -ENOLCK (and generate a scary-looking
+ * an existing lease, the ``(*lease)->fl_lmops->lm_break`` operation must be
+ * set; if not, this function will return -ENOLCK (and generate a scary-looking
* stack trace).
*
* The "priv" pointer is passed directly to the lm_setup function as-is. It
@@ -1972,15 +1972,13 @@ EXPORT_SYMBOL(locks_lock_inode_wait);
* @cmd: the type of lock to apply.
*
* Apply a %FL_FLOCK style lock to an open file descriptor.
- * The @cmd can be one of
+ * The @cmd can be one of:
*
- * %LOCK_SH -- a shared lock.
- *
- * %LOCK_EX -- an exclusive lock.
- *
- * %LOCK_UN -- remove an existing lock.
- *
- * %LOCK_MAND -- a `mandatory' flock. This exists to emulate Windows Share Modes.
+ * - %LOCK_SH -- a shared lock.
+ * - %LOCK_EX -- an exclusive lock.
+ * - %LOCK_UN -- remove an existing lock.
+ * - %LOCK_MAND -- a 'mandatory' flock.
+ * This exists to emulate Windows Share Modes.
*
* %LOCK_MAND can be combined with %LOCK_READ or %LOCK_WRITE to allow other
* processes read and write access respectively.
@@ -2086,26 +2084,22 @@ static void posix_lock_to_flock64(struct flock64 *flock, struct file_lock *fl)
/* Report the first existing lock that would conflict with l.
* This implements the F_GETLK command of fcntl().
*/
-int fcntl_getlk(struct file *filp, unsigned int cmd, struct flock __user *l)
+int fcntl_getlk(struct file *filp, unsigned int cmd, struct flock *flock)
{
struct file_lock file_lock;
- struct flock flock;
int error;
- error = -EFAULT;
- if (copy_from_user(&flock, l, sizeof(flock)))
- goto out;
error = -EINVAL;
- if ((flock.l_type != F_RDLCK) && (flock.l_type != F_WRLCK))
+ if (flock->l_type != F_RDLCK && flock->l_type != F_WRLCK)
goto out;
- error = flock_to_posix_lock(filp, &file_lock, &flock);
+ error = flock_to_posix_lock(filp, &file_lock, flock);
if (error)
goto out;
if (cmd == F_OFD_GETLK) {
error = -EINVAL;
- if (flock.l_pid != 0)
+ if (flock->l_pid != 0)
goto out;
cmd = F_GETLK;
@@ -2117,15 +2111,12 @@ int fcntl_getlk(struct file *filp, unsigned int cmd, struct flock __user *l)
if (error)
goto out;
- flock.l_type = file_lock.fl_type;
+ flock->l_type = file_lock.fl_type;
if (file_lock.fl_type != F_UNLCK) {
- error = posix_lock_to_flock(&flock, &file_lock);
+ error = posix_lock_to_flock(flock, &file_lock);
if (error)
goto rel_priv;
}
- error = -EFAULT;
- if (!copy_to_user(l, &flock, sizeof(flock)))
- error = 0;
rel_priv:
locks_release_private(&file_lock);
out:
@@ -2218,26 +2209,16 @@ check_fmode_for_setlk(struct file_lock *fl)
* This implements both the F_SETLK and F_SETLKW commands of fcntl().
*/
int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd,
- struct flock __user *l)
+ struct flock *flock)
{
struct file_lock *file_lock = locks_alloc_lock();
- struct flock flock;
- struct inode *inode;
+ struct inode *inode = locks_inode(filp);
struct file *f;
int error;
if (file_lock == NULL)
return -ENOLCK;
- inode = locks_inode(filp);
-
- /*
- * This might block, so we do it before checking the inode.
- */
- error = -EFAULT;
- if (copy_from_user(&flock, l, sizeof(flock)))
- goto out;
-
/* Don't allow mandatory locks on files that may be memory mapped
* and shared.
*/
@@ -2246,7 +2227,7 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd,
goto out;
}
- error = flock_to_posix_lock(filp, file_lock, &flock);
+ error = flock_to_posix_lock(filp, file_lock, flock);
if (error)
goto out;
@@ -2261,7 +2242,7 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd,
switch (cmd) {
case F_OFD_SETLK:
error = -EINVAL;
- if (flock.l_pid != 0)
+ if (flock->l_pid != 0)
goto out;
cmd = F_SETLK;
@@ -2270,7 +2251,7 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd,
break;
case F_OFD_SETLKW:
error = -EINVAL;
- if (flock.l_pid != 0)
+ if (flock->l_pid != 0)
goto out;
cmd = F_SETLKW;
@@ -2315,26 +2296,22 @@ out:
/* Report the first existing lock that would conflict with l.
* This implements the F_GETLK command of fcntl().
*/
-int fcntl_getlk64(struct file *filp, unsigned int cmd, struct flock64 __user *l)
+int fcntl_getlk64(struct file *filp, unsigned int cmd, struct flock64 *flock)
{
struct file_lock file_lock;
- struct flock64 flock;
int error;
- error = -EFAULT;
- if (copy_from_user(&flock, l, sizeof(flock)))
- goto out;
error = -EINVAL;
- if ((flock.l_type != F_RDLCK) && (flock.l_type != F_WRLCK))
+ if (flock->l_type != F_RDLCK && flock->l_type != F_WRLCK)
goto out;
- error = flock64_to_posix_lock(filp, &file_lock, &flock);
+ error = flock64_to_posix_lock(filp, &file_lock, flock);
if (error)
goto out;
if (cmd == F_OFD_GETLK) {
error = -EINVAL;
- if (flock.l_pid != 0)
+ if (flock->l_pid != 0)
goto out;
cmd = F_GETLK64;
@@ -2346,13 +2323,9 @@ int fcntl_getlk64(struct file *filp, unsigned int cmd, struct flock64 __user *l)
if (error)
goto out;
- flock.l_type = file_lock.fl_type;
+ flock->l_type = file_lock.fl_type;
if (file_lock.fl_type != F_UNLCK)
- posix_lock_to_flock64(&flock, &file_lock);
-
- error = -EFAULT;
- if (!copy_to_user(l, &flock, sizeof(flock)))
- error = 0;
+ posix_lock_to_flock64(flock, &file_lock);
locks_release_private(&file_lock);
out:
@@ -2363,26 +2336,16 @@ out:
* This implements both the F_SETLK and F_SETLKW commands of fcntl().
*/
int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd,
- struct flock64 __user *l)
+ struct flock64 *flock)
{
struct file_lock *file_lock = locks_alloc_lock();
- struct flock64 flock;
- struct inode *inode;
+ struct inode *inode = locks_inode(filp);
struct file *f;
int error;
if (file_lock == NULL)
return -ENOLCK;
- /*
- * This might block, so we do it before checking the inode.
- */
- error = -EFAULT;
- if (copy_from_user(&flock, l, sizeof(flock)))
- goto out;
-
- inode = locks_inode(filp);
-
/* Don't allow mandatory locks on files that may be memory mapped
* and shared.
*/
@@ -2391,7 +2354,7 @@ int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd,
goto out;
}
- error = flock64_to_posix_lock(filp, file_lock, &flock);
+ error = flock64_to_posix_lock(filp, file_lock, flock);
if (error)
goto out;
@@ -2406,7 +2369,7 @@ int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd,
switch (cmd) {
case F_OFD_SETLK:
error = -EINVAL;
- if (flock.l_pid != 0)
+ if (flock->l_pid != 0)
goto out;
cmd = F_SETLK64;
@@ -2415,7 +2378,7 @@ int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd,
break;
case F_OFD_SETLKW:
error = -EINVAL;
- if (flock.l_pid != 0)
+ if (flock->l_pid != 0)
goto out;
cmd = F_SETLKW64;
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 2be32955d7f2..6eef95c585e3 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -1464,41 +1464,34 @@ do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
__be32
nfsd_readlink(struct svc_rqst *rqstp, struct svc_fh *fhp, char *buf, int *lenp)
{
- mm_segment_t oldfs;
__be32 err;
- int host_err;
+ const char *link;
struct path path;
+ DEFINE_DELAYED_CALL(done);
+ int len;
err = fh_verify(rqstp, fhp, S_IFLNK, NFSD_MAY_NOP);
- if (err)
- goto out;
+ if (unlikely(err))
+ return err;
path.mnt = fhp->fh_export->ex_path.mnt;
path.dentry = fhp->fh_dentry;
- err = nfserr_inval;
- if (!d_is_symlink(path.dentry))
- goto out;
+ if (unlikely(!d_is_symlink(path.dentry)))
+ return nfserr_inval;
touch_atime(&path);
- /* N.B. Why does this call need a get_fs()??
- * Remove the set_fs and watch the fireworks:-) --okir
- */
- oldfs = get_fs(); set_fs(KERNEL_DS);
- host_err = vfs_readlink(path.dentry, (char __user *)buf, *lenp);
- set_fs(oldfs);
+ link = vfs_get_link(path.dentry, &done);
+ if (IS_ERR(link))
+ return nfserrno(PTR_ERR(link));
- if (host_err < 0)
- goto out_nfserr;
- *lenp = host_err;
- err = 0;
-out:
- return err;
-
-out_nfserr:
- err = nfserrno(host_err);
- goto out;
+ len = strlen(link);
+ if (len < *lenp)
+ *lenp = len;
+ memcpy(buf, link, *lenp);
+ do_delayed_call(&done);
+ return 0;
}
/*
diff --git a/fs/statfs.c b/fs/statfs.c
index 4e4623c7a126..41a6a82da5e2 100644
--- a/fs/statfs.c
+++ b/fs/statfs.c
@@ -244,6 +244,7 @@ SYSCALL_DEFINE2(ustat, unsigned, dev, struct ustat __user *, ubuf)
#ifdef CONFIG_COMPAT
static int put_compat_statfs(struct compat_statfs __user *ubuf, struct kstatfs *kbuf)
{
+ struct compat_statfs buf;
if (sizeof ubuf->f_blocks == 4) {
if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail |
kbuf->f_bsize | kbuf->f_frsize) & 0xffffffff00000000ULL)
@@ -257,20 +258,20 @@ static int put_compat_statfs(struct compat_statfs __user *ubuf, struct kstatfs *
&& (kbuf->f_ffree & 0xffffffff00000000ULL))
return -EOVERFLOW;
}
- if (!access_ok(VERIFY_WRITE, ubuf, sizeof(*ubuf)) ||
- __put_user(kbuf->f_type, &ubuf->f_type) ||
- __put_user(kbuf->f_bsize, &ubuf->f_bsize) ||
- __put_user(kbuf->f_blocks, &ubuf->f_blocks) ||
- __put_user(kbuf->f_bfree, &ubuf->f_bfree) ||
- __put_user(kbuf->f_bavail, &ubuf->f_bavail) ||
- __put_user(kbuf->f_files, &ubuf->f_files) ||
- __put_user(kbuf->f_ffree, &ubuf->f_ffree) ||
- __put_user(kbuf->f_namelen, &ubuf->f_namelen) ||
- __put_user(kbuf->f_fsid.val[0], &ubuf->f_fsid.val[0]) ||
- __put_user(kbuf->f_fsid.val[1], &ubuf->f_fsid.val[1]) ||
- __put_user(kbuf->f_frsize, &ubuf->f_frsize) ||
- __put_user(kbuf->f_flags, &ubuf->f_flags) ||
- __clear_user(ubuf->f_spare, sizeof(ubuf->f_spare)))
+ memset(&buf, 0, sizeof(struct compat_statfs));
+ buf.f_type = kbuf->f_type;
+ buf.f_bsize = kbuf->f_bsize;
+ buf.f_blocks = kbuf->f_blocks;
+ buf.f_bfree = kbuf->f_bfree;
+ buf.f_bavail = kbuf->f_bavail;
+ buf.f_files = kbuf->f_files;
+ buf.f_ffree = kbuf->f_ffree;
+ buf.f_namelen = kbuf->f_namelen;
+ buf.f_fsid.val[0] = kbuf->f_fsid.val[0];
+ buf.f_fsid.val[1] = kbuf->f_fsid.val[1];
+ buf.f_frsize = kbuf->f_frsize;
+ buf.f_flags = kbuf->f_flags;
+ if (copy_to_user(ubuf, &buf, sizeof(struct compat_statfs)))
return -EFAULT;
return 0;
}
@@ -299,6 +300,7 @@ COMPAT_SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct compat_statfs __user *,
static int put_compat_statfs64(struct compat_statfs64 __user *ubuf, struct kstatfs *kbuf)
{
+ struct compat_statfs64 buf;
if (sizeof(ubuf->f_bsize) == 4) {
if ((kbuf->f_type | kbuf->f_bsize | kbuf->f_namelen |
kbuf->f_frsize | kbuf->f_flags) & 0xffffffff00000000ULL)
@@ -312,20 +314,20 @@ static int put_compat_statfs64(struct compat_statfs64 __user *ubuf, struct kstat
&& (kbuf->f_ffree & 0xffffffff00000000ULL))
return -EOVERFLOW;
}
- if (!access_ok(VERIFY_WRITE, ubuf, sizeof(*ubuf)) ||
- __put_user(kbuf->f_type, &ubuf->f_type) ||
- __put_user(kbuf->f_bsize, &ubuf->f_bsize) ||
- __put_user(kbuf->f_blocks, &ubuf->f_blocks) ||
- __put_user(kbuf->f_bfree, &ubuf->f_bfree) ||
- __put_user(kbuf->f_bavail, &ubuf->f_bavail) ||
- __put_user(kbuf->f_files, &ubuf->f_files) ||
- __put_user(kbuf->f_ffree, &ubuf->f_ffree) ||
- __put_user(kbuf->f_namelen, &ubuf->f_namelen) ||
- __put_user(kbuf->f_fsid.val[0], &ubuf->f_fsid.val[0]) ||
- __put_user(kbuf->f_fsid.val[1], &ubuf->f_fsid.val[1]) ||
- __put_user(kbuf->f_frsize, &ubuf->f_frsize) ||
- __put_user(kbuf->f_flags, &ubuf->f_flags) ||
- __clear_user(ubuf->f_spare, sizeof(ubuf->f_spare)))
+ memset(&buf, 0, sizeof(struct compat_statfs64));
+ buf.f_type = kbuf->f_type;
+ buf.f_bsize = kbuf->f_bsize;
+ buf.f_blocks = kbuf->f_blocks;
+ buf.f_bfree = kbuf->f_bfree;
+ buf.f_bavail = kbuf->f_bavail;
+ buf.f_files = kbuf->f_files;
+ buf.f_ffree = kbuf->f_ffree;
+ buf.f_namelen = kbuf->f_namelen;
+ buf.f_fsid.val[0] = kbuf->f_fsid.val[0];
+ buf.f_fsid.val[1] = kbuf->f_fsid.val[1];
+ buf.f_frsize = kbuf->f_frsize;
+ buf.f_flags = kbuf->f_flags;
+ if (copy_to_user(ubuf, &buf, sizeof(struct compat_statfs64)))
return -EFAULT;
return 0;
}