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.le...@oracle.com> Acked-by: Hannes Frederic Sowa <han...@stressinduktion.org> Tested-by: Sasha Levin <sasha.le...@oracle.com> Signed-off-by: Cong Wang <xiyou.wangc...@gmail.com> --- net/ipv6/addrconf.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 17f8e7e..1f21087 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -5369,13 +5369,10 @@ static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write, 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); -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html