diff --git a/fs/fcntl.c b/fs/fcntl.c index afed3b364979..f525bc75c07d 100644 --- a/fs/fcntl.c +++ b/fs/fcntl.c @@ -452,57 +452,56 @@ 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 get_compat_flock64(struct flock *kfl, struct compat_flock64 __user *ufl) +{ + struct compat_flock64 fl; + + if (copy_from_user(&fl, ufl, sizeof(struct compat_flock64))) + return -EFAULT; + copy_flock_fields(*kfl, fl); return 0; } static int put_compat_flock(struct flock *kfl, struct compat_flock __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_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; } -#ifndef HAVE_ARCH_GET_COMPAT_FLOCK64 -static int get_compat_flock64(struct flock *kfl, struct compat_flock64 __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)) - 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)