net: ipconfig: Don't override command-line hostnames or domains

[ Upstream commit b508d5fb69c2211a1b860fc058aafbefc3b3c3cd ]

If the user specifies a hostname or domain name as part of the ip=
command-line option, preserve it and don't overwrite it with one
supplied by DHCP/BOOTP.

For instance, ip=::::myhostname::dhcp will use "myhostname" rather than
ignoring and overwriting it.

Fix the comment on ic_bootp_string that suggests it only copies a string
"if not already set"; it doesn't have any such logic.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Josh Triplett
2021-06-01 18:38:41 -07:00
committed by Greg Kroah-Hartman
parent 511a010291
commit ecd26536ec

View File

@@ -870,7 +870,7 @@ static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_d
/* /*
* Copy BOOTP-supplied string if not already set. * Copy BOOTP-supplied string
*/ */
static int __init ic_bootp_string(char *dest, char *src, int len, int max) static int __init ic_bootp_string(char *dest, char *src, int len, int max)
{ {
@@ -919,11 +919,14 @@ static void __init ic_do_bootp_ext(u8 *ext)
} }
break; break;
case 12: /* Host name */ case 12: /* Host name */
if (!ic_host_name_set) {
ic_bootp_string(utsname()->nodename, ext+1, *ext, ic_bootp_string(utsname()->nodename, ext+1, *ext,
__NEW_UTS_LEN); __NEW_UTS_LEN);
ic_host_name_set = 1; ic_host_name_set = 1;
}
break; break;
case 15: /* Domain name (DNS) */ case 15: /* Domain name (DNS) */
if (!ic_domain[0])
ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain)); ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
break; break;
case 17: /* Root path */ case 17: /* Root path */