diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c index 31b7efd94d66..43a2508ac696 100644 --- a/fs/compat_ioctl.c +++ b/fs/compat_ioctl.c @@ -686,7 +686,8 @@ static int dev_ifconf(unsigned int fd, unsigned int cmd, unsigned long arg) ifr = ifc.ifc_req; ifr32 = compat_ptr(ifc32.ifcbuf); - for (i = 0, j = 0; i < ifc32.ifc_len && j < ifc.ifc_len; + for (i = 0, j = 0; + i + sizeof (struct ifreq32) < ifc32.ifc_len && j < ifc.ifc_len; i += sizeof (struct ifreq32), j += sizeof (struct ifreq)) { if (copy_in_user(ifr32, ifr, sizeof (struct ifreq32))) return -EFAULT; @@ -702,10 +703,7 @@ static int dev_ifconf(unsigned int fd, unsigned int cmd, unsigned long arg) i = ((i / sizeof(struct ifreq)) * sizeof(struct ifreq32)); ifc32.ifc_len = i; } else { - if (i <= ifc32.ifc_len) - ifc32.ifc_len = i; - else - ifc32.ifc_len = i - sizeof (struct ifreq32); + ifc32.ifc_len = i; } if (copy_to_user(compat_ptr(arg), &ifc32, sizeof(struct ifconf32))) return -EFAULT;