From: Dave Taht dave.taht@gmail.com
commit 65cab850f0eeaa9180bd2e10a231964f33743edf upstream.
While most distributions long ago switched to the iproute2 suite of utilities, which allow class-e (240.0.0.0/4) address assignment, distributions relying on busybox, toybox and other forms of ifconfig cannot assign class-e addresses without this kernel patch.
While CIDR has been obsolete for 2 decades, and a survey of all the open source code in the world shows the IN_whatever macros are also obsolete... rather than obsolete CIDR from this ioctl entirely, this patch merely enables class-e assignment, sanely.
Signed-off-by: Dave Taht dave.taht@gmail.com Signed-off-by: David S. Miller davem@davemloft.net --- - This commit is upstream in v4.20 - This should ve applied for stable v4.19.y, v4.14.y and v4.9.y --- include/uapi/linux/in.h | 10 +++++++--- net/ipv4/devinet.c | 5 +++-- net/ipv4/ipconfig.c | 2 ++ 3 files changed, 12 insertions(+), 5 deletions(-)
diff --git a/include/uapi/linux/in.h b/include/uapi/linux/in.h index 48e8a225b985..f6052e70bf40 100644 --- a/include/uapi/linux/in.h +++ b/include/uapi/linux/in.h @@ -266,10 +266,14 @@ struct sockaddr_in {
#define IN_CLASSD(a) ((((long int) (a)) & 0xf0000000) == 0xe0000000) #define IN_MULTICAST(a) IN_CLASSD(a) -#define IN_MULTICAST_NET 0xF0000000 +#define IN_MULTICAST_NET 0xe0000000
-#define IN_EXPERIMENTAL(a) ((((long int) (a)) & 0xf0000000) == 0xf0000000) -#define IN_BADCLASS(a) IN_EXPERIMENTAL((a)) +#define IN_BADCLASS(a) ((((long int) (a) ) == 0xffffffff) +#define IN_EXPERIMENTAL(a) IN_BADCLASS((a)) + +#define IN_CLASSE(a) ((((long int) (a)) & 0xf0000000) == 0xf0000000) +#define IN_CLASSE_NET 0xffffffff +#define IN_CLASSE_NSHIFT 0
/* Address to accept any incoming messages. */ #define INADDR_ANY ((unsigned long int) 0x00000000) diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index ea4bd8a52422..e38042933a27 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -941,17 +941,18 @@ static int inet_abc_len(__be32 addr) { int rc = -1; /* Something else, probably a multicast. */
- if (ipv4_is_zeronet(addr)) + if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr)) rc = 0; else { __u32 haddr = ntohl(addr); - if (IN_CLASSA(haddr)) rc = 8; else if (IN_CLASSB(haddr)) rc = 16; else if (IN_CLASSC(haddr)) rc = 24; + else if (IN_CLASSE(haddr)) + rc = 32; }
return rc; diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c index 88212615bf4c..2393e5c106bf 100644 --- a/net/ipv4/ipconfig.c +++ b/net/ipv4/ipconfig.c @@ -429,6 +429,8 @@ static int __init ic_defaults(void) ic_netmask = htonl(IN_CLASSB_NET); else if (IN_CLASSC(ntohl(ic_myaddr))) ic_netmask = htonl(IN_CLASSC_NET); + else if (IN_CLASSE(ntohl(ic_myaddr))) + ic_netmask = htonl(IN_CLASSE_NET); else { pr_err("IP-Config: Unable to guess netmask for address %pI4\n", &ic_myaddr);