[PATCH] Fix regression in ip command line processing

From: Amos Waterland
Date: Sat Jan 05 2008 - 22:59:18 EST


The recent changes for ip command line processing fixed some problems
but unfortunately broke some common usage scenarios. In current
2.6.24-rc6 the following command line results in no IP address
assignment, which is surely a regression:

ip=10.0.2.15::10.0.2.2:255.255.255.0::eth0:off

Please find below a patch that works for all cases I can find.

Signed-off-by: Amos Waterland <apw@xxxxxxxxxx>

---

For convenience, here are the test cases phrased as qemu invocations:

ADDRESS ASSIGNED

qemu -kernel x86/arch/i386/boot/bzImage /dev/zero -append "ip=on"
qemu -kernel x86/arch/i386/boot/bzImage /dev/zero -append "ip=dhcp"
qemu -kernel x86/arch/i386/boot/bzImage /dev/zero -append "ip=both"
qemu -kernel x86/arch/i386/boot/bzImage /dev/zero -append "ip=any"
qemu -kernel x86/arch/i386/boot/bzImage /dev/zero -append "ip=::::::on"
qemu -kernel x86/arch/i386/boot/bzImage /dev/zero -append "ip=::::::dhcp"
qemu -kernel x86/arch/i386/boot/bzImage /dev/zero -append "ip=10.0.2.15::10.0.2.2:255.255.255.0::eth0:off"
qemu -kernel x86/arch/i386/boot/bzImage /dev/zero -append "ip=10.0.2.15::10.0.2.2:255.255.255.0::eth0:on"

ADDRESS NOT ASSIGNED

qemu -kernel x86/arch/i386/boot/bzImage /dev/zero -append "ip="
qemu -kernel x86/arch/i386/boot/bzImage /dev/zero -append "ip=off"
qemu -kernel x86/arch/i386/boot/bzImage /dev/zero -append "ip=::::::off"

---

Documentation/nfsroot.txt | 1 +
net/ipv4/ipconfig.c | 19 +++++++++++++++----
2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/Documentation/nfsroot.txt b/Documentation/nfsroot.txt
index c86dd38..1a4d199 100644
--- a/Documentation/nfsroot.txt
+++ b/Documentation/nfsroot.txt
@@ -145,6 +145,7 @@ ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>
this option.

off or none: don't use autoconfiguration
+ (do static IP assignment instead)
on or any: use any protocol available in the kernel
(default)
dhcp: use DHCP
diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c
index 56a6757..8563b2e 100644
--- a/net/ipv4/ipconfig.c
+++ b/net/ipv4/ipconfig.c
@@ -1404,8 +1404,7 @@ static int __init ic_proto_name(char *name)
return 1;
}
if (!strcmp(name, "off") || !strcmp(name, "none")) {
- ic_enable = 0;
- return 1;
+ return 0;
}
#ifdef CONFIG_IP_PNP_DHCP
else if (!strcmp(name, "dhcp")) {
@@ -1442,10 +1441,20 @@ static int __init ip_auto_config_setup(char *addrs)
ic_set_manually = 1;
ic_enable = 1;

+ /*
+ * If any dhcp, bootp etc options are set, leave autoconfig on
+ * and skip the below static IP processing.
+ */
if (ic_proto_name(addrs))
return 1;

- /* Parse the whole string */
+ /* If no static IP is given, turn off autoconfig and bail. */
+ if (*addrs == 0 || strcmp(addrs, "off") == 0 || strcmp(addrs, "none") == 0) {
+ ic_enable = 0;
+ return 1;
+ }
+
+ /* Parse string for static IP assignment. */
ip = addrs;
while (ip && *ip) {
if ((cp = strchr(ip, ':')))
@@ -1483,7 +1492,9 @@ static int __init ip_auto_config_setup(char *addrs)
strlcpy(user_dev_name, ip, sizeof(user_dev_name));
break;
case 6:
- ic_proto_name(ip);
+ if (ic_proto_name(ip) == 0 && ic_myaddr == NONE) {
+ ic_enable = 0;
+ }
break;
}
}
--
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