On Thu, May 27, 2010 at 06:58:03PM +0900, Takuya Yoshikawa wrote: > copy_to/from_user() returns the number of bytes that could not be copied. > > So we need to check if it is not zero, and in that case, we should return > the error number -EFAULT rather than directly return the return value from > copy_to/from_user(). > > Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@xxxxxxxxxxxxx> Thanks, applied. > --- > drivers/vhost/vhost.c | 51 ++++++++++++++++++++++++++---------------------- > 1 files changed, 28 insertions(+), 23 deletions(-) > > diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > index 5c9c657..9633a3c 100644 > --- a/drivers/vhost/vhost.c > +++ b/drivers/vhost/vhost.c > @@ -320,10 +320,8 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) > { > struct vhost_memory mem, *newmem, *oldmem; > unsigned long size = offsetof(struct vhost_memory, regions); > - long r; > - r = copy_from_user(&mem, m, size); > - if (r) > - return r; > + if (copy_from_user(&mem, m, size)) > + return -EFAULT; > if (mem.padding) > return -EOPNOTSUPP; > if (mem.nregions > VHOST_MEMORY_MAX_NREGIONS) > @@ -333,11 +331,10 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) > return -ENOMEM; > > memcpy(newmem, &mem, size); > - r = copy_from_user(newmem->regions, m->regions, > - mem.nregions * sizeof *m->regions); > - if (r) { > + if (copy_from_user(newmem->regions, m->regions, > + mem.nregions * sizeof *m->regions)) { > kfree(newmem); > - return r; > + return -EFAULT; > } > > if (!memory_access_ok(d, newmem, vhost_has_feature(d, VHOST_F_LOG_ALL))) > @@ -389,9 +386,10 @@ static long vhost_set_vring(struct vhost_dev *d, int ioctl, void __user *argp) > r = -EBUSY; > break; > } > - r = copy_from_user(&s, argp, sizeof s); > - if (r < 0) > + if (copy_from_user(&s, argp, sizeof s)) { > + r = -EFAULT; > break; > + } > if (!s.num || s.num > 0xffff || (s.num & (s.num - 1))) { > r = -EINVAL; > break; > @@ -405,9 +403,10 @@ static long vhost_set_vring(struct vhost_dev *d, int ioctl, void __user *argp) > r = -EBUSY; > break; > } > - r = copy_from_user(&s, argp, sizeof s); > - if (r < 0) > + if (copy_from_user(&s, argp, sizeof s)) { > + r = -EFAULT; > break; > + } > if (s.num > 0xffff) { > r = -EINVAL; > break; > @@ -419,12 +418,14 @@ static long vhost_set_vring(struct vhost_dev *d, int ioctl, void __user *argp) > case VHOST_GET_VRING_BASE: > s.index = idx; > s.num = vq->last_avail_idx; > - r = copy_to_user(argp, &s, sizeof s); > + if (copy_to_user(argp, &s, sizeof s)) > + r = -EFAULT; > break; > case VHOST_SET_VRING_ADDR: > - r = copy_from_user(&a, argp, sizeof a); > - if (r < 0) > + if (copy_from_user(&a, argp, sizeof a)) { > + r = -EFAULT; > break; > + } > if (a.flags & ~(0x1 << VHOST_VRING_F_LOG)) { > r = -EOPNOTSUPP; > break; > @@ -477,9 +478,10 @@ static long vhost_set_vring(struct vhost_dev *d, int ioctl, void __user *argp) > vq->used = (void __user *)(unsigned long)a.used_user_addr; > break; > case VHOST_SET_VRING_KICK: > - r = copy_from_user(&f, argp, sizeof f); > - if (r < 0) > + if (copy_from_user(&f, argp, sizeof f)) { > + r = -EFAULT; > break; > + } > eventfp = f.fd == -1 ? NULL : eventfd_fget(f.fd); > if (IS_ERR(eventfp)) { > r = PTR_ERR(eventfp); > @@ -492,9 +494,10 @@ static long vhost_set_vring(struct vhost_dev *d, int ioctl, void __user *argp) > filep = eventfp; > break; > case VHOST_SET_VRING_CALL: > - r = copy_from_user(&f, argp, sizeof f); > - if (r < 0) > + if (copy_from_user(&f, argp, sizeof f)) { > + r = -EFAULT; > break; > + } > eventfp = f.fd == -1 ? NULL : eventfd_fget(f.fd); > if (IS_ERR(eventfp)) { > r = PTR_ERR(eventfp); > @@ -510,9 +513,10 @@ static long vhost_set_vring(struct vhost_dev *d, int ioctl, void __user *argp) > filep = eventfp; > break; > case VHOST_SET_VRING_ERR: > - r = copy_from_user(&f, argp, sizeof f); > - if (r < 0) > + if (copy_from_user(&f, argp, sizeof f)) { > + r = -EFAULT; > break; > + } > eventfp = f.fd == -1 ? NULL : eventfd_fget(f.fd); > if (IS_ERR(eventfp)) { > r = PTR_ERR(eventfp); > @@ -575,9 +579,10 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, unsigned long arg) > r = vhost_set_memory(d, argp); > break; > case VHOST_SET_LOG_BASE: > - r = copy_from_user(&p, argp, sizeof p); > - if (r < 0) > + if (copy_from_user(&p, argp, sizeof p)) { > + r = -EFAULT; > break; > + } > if ((u64)(unsigned long)p != p) { > r = -EFAULT; > break; > -- > 1.7.0.4 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html