[linuxkernelnewbies] Linux-Kernel: [PATCH 3/10] UML - Fix UML network driver endianness bugs

[Peter Teoh]

http://linux.derkeiler.com/Mailing-Lists/Kernel/2005-10/6783.html From: Bodo Stroesser <bstroes...@fujitsu-siemens.com> ifa->ifa_address and ifa->ifa_mask are defined as __u32, but used as if they were char[4]. Network code uses htons() to convert it. So UML's method to access these fields is wrong for bigendians (e.g. s390) I replaced bytewise copying by memcpy(), maybe even that might be removed, if ifa->ifa_address/mask may be used immediately. Signed-off-by: Bodo Stroesser <bstroes...@fujitsu-siemens.com> Signed-off-by: Jeff Dike <jd...@addtoit.com> diff -puN arch/um/drivers/net_kern.c~fix-net-ordering arch/um/drivers/net_kern.c --- linux-2.6.13-rc5/arch/um/drivers/net_kern.c~fix-net-ordering 2005-08-10 14:57:13.296403116 +0200 +++ linux-2.6.13-rc5-root/arch/um/drivers/net_kern.c 2005-08-10 14:57:13.303400833 +0200 @@ -95,7 +95,6 @@ irqreturn_t uml_net_interrupt(int irq, v  static int uml_net_open(struct net_device *dev)  {          struct uml_net_private *lp = dev->priv; - char addr[sizeof("255.255.255.255\0")];          int err;            spin_lock(&lp->lock); @@ -106,7 +105,7 @@ static int uml_net_open(struct net_devic          }            if(!lp->have_mac){ - dev_ip_addr(dev, addr, &lp->mac[2]); + dev_ip_addr(dev, &lp->mac[2]);                   set_ether_mac(dev, lp->mac);          }   @@ -663,8 +662,6 @@ static int uml_inetaddr_event(struct not                                void *ptr)  {          struct in_ifaddr *ifa = ptr; - u32 addr = ifa->ifa_address; - u32 netmask = ifa->ifa_mask;          struct net_device *dev = ifa->ifa_dev->dev;          struct uml_net_private *lp;          void (*proc)(unsigned char *, unsigned char *, void *); @@ -684,14 +681,8 @@ static int uml_inetaddr_event(struct not                  break;          }          if(proc != NULL){ - addr_buf[0] = addr & 0xff; - addr_buf[1] = (addr >> 8) & 0xff; - addr_buf[2] = (addr >> 16) & 0xff; - addr_buf[3] = addr >> 24; - netmask_buf[0] = netmask & 0xff; - netmask_buf[1] = (netmask >> 8) & 0xff; - netmask_buf[2] = (netmask >> 16) & 0xff; - netmask_buf[3] = netmask >> 24; + memcpy(addr_buf, &ifa->ifa_address, sizeof(addr_buf)); + memcpy(netmask_buf, &ifa->ifa_mask, sizeof(netmask_buf));                  (*proc)(addr_buf, netmask_buf, &lp->user);          }          return(NOTIFY_DONE); @@ -773,27 +764,18 @@ int setup_etheraddr(char *str, unsigned          return(1);  }   -void dev_ip_addr(void *d, char *buf, char *bin_buf) +void dev_ip_addr(void *d, unsigned char *bin_buf)  {          struct net_device *dev = d;          struct in_device *ip = dev->ip_ptr;          struct in_ifaddr *in; - u32 addr;            if((ip == NULL) || ((in = ip->ifa_list) == NULL)){                  printk(KERN_WARNING "dev_ip_addr - device not assigned an "                         "IP address\n");                  return;          } - addr = in->ifa_address; - sprintf(buf, "%d.%d.%d.%d", addr & 0xff, (addr >> 8) & 0xff, - (addr >> 16) & 0xff, addr >> 24); - if(bin_buf){ - bin_buf[0] = addr & 0xff; - bin_buf[1] = (addr >> 8) & 0xff; - bin_buf[2] = (addr >> 16) & 0xff; - bin_buf[3] = addr >> 24; - } + memcpy(bin_buf, &in->ifa_address, sizeof(in->ifa_address));  }    void set_ether_mac(void *d, unsigned char *addr) @@ -828,14 +810,8 @@ void iter_addresses(void *d, void (*cb)(          if(ip == NULL) return;          in = ip->ifa_list;          while(in != NULL){ - address[0] = in->ifa_address & 0xff; - address[1] = (in->ifa_address >> 8) & 0xff; - address[2] = (in->ifa_address >> 16) & 0xff; - address[3] = in->ifa_address >> 24; - netmask[0] = in->ifa_mask & 0xff; - netmask[1] = (in->ifa_mask >> 8) & 0xff; - netmask[2] = (in->ifa_mask >> 16) & 0xff; - netmask[3] = in->ifa_mask >> 24; + memcpy(address, &in->ifa_address, sizeof(address)); + memcpy(netmask, &in->ifa_mask, sizeof(netmask));                  (*cb)(address, netmask, arg);                  in = in->ifa_next;          } diff -puN arch/um/include/net_user.h~fix-net-ordering arch/um/include/net_user.h --- linux-2.6.13-rc5/arch/um/include/net_user.h~fix-net-ordering 2005-08-10 14:57:13.299402138 +0200 +++ linux-2.6.13-rc5-root/arch/um/include/net_user.h 2005-08-10 14:57:13.304400507 +0200 @@ -25,7 +25,7 @@ struct net_user_info {  };    extern void ether_user_init(void *data, void *dev); -extern void dev_ip_addr(void *d, char *buf, char *bin_buf); +extern void dev_ip_addr(void *d, unsigned char *bin_buf);  extern void set_ether_mac(void *d, unsigned char *addr);  extern void iter_addresses(void *d, void (*cb)(unsigned char *,                                                 unsigned char *, void *), _