| From foo@baz Tue Jan 26 21:35:02 PST 2016 |
| From: WANG Cong <xiyou.wangcong@gmail.com> |
| Date: Mon, 21 Dec 2015 10:55:45 -0800 |
| Subject: addrconf: always initialize sysctl table data |
| |
| From: WANG Cong <xiyou.wangcong@gmail.com> |
| |
| [ Upstream commit 5449a5ca9bc27dd51a462de7ca0b1cd861cd2bd0 ] |
| |
| When sysctl performs restrict writes, it allows to write from |
| a middle position of a sysctl file, which requires us to initialize |
| the table data before calling proc_dostring() for the write case. |
| |
| Fixes: 3d1bec99320d ("ipv6: introduce secret_stable to ipv6_devconf") |
| Reported-by: Sasha Levin <sasha.levin@oracle.com> |
| Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> |
| Tested-by: Sasha Levin <sasha.levin@oracle.com> |
| Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/ipv6/addrconf.c | 11 ++++------- |
| 1 file changed, 4 insertions(+), 7 deletions(-) |
| |
| --- a/net/ipv6/addrconf.c |
| +++ b/net/ipv6/addrconf.c |
| @@ -5349,13 +5349,10 @@ static int addrconf_sysctl_stable_secret |
| goto out; |
| } |
| |
| - if (!write) { |
| - err = snprintf(str, sizeof(str), "%pI6", |
| - &secret->secret); |
| - if (err >= sizeof(str)) { |
| - err = -EIO; |
| - goto out; |
| - } |
| + err = snprintf(str, sizeof(str), "%pI6", &secret->secret); |
| + if (err >= sizeof(str)) { |
| + err = -EIO; |
| + goto out; |
| } |
| |
| err = proc_dostring(&lctl, write, buffer, lenp, ppos); |