| Message ID | 20200827095033.3265848-1-hegtvedt@cisco.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] ioctl: only memset non-NULL link settings | expand |
diff --git a/ethtool.c b/ethtool.c index e32a93b..606af3e 100644 --- a/ethtool.c +++ b/ethtool.c @@ -3048,10 +3048,11 @@ static int do_sset(struct cmd_context *ctx) struct ethtool_link_usettings *link_usettings; link_usettings = do_ioctl_glinksettings(ctx); - memset(&link_usettings->deprecated, 0, - sizeof(link_usettings->deprecated)); if (link_usettings == NULL) link_usettings = do_ioctl_gset(ctx); + else + memset(&link_usettings->deprecated, 0, + sizeof(link_usettings->deprecated)); if (link_usettings == NULL) { perror("Cannot get current device settings"); err = -1;
In commit bef780467fa ('ioctl: do not pass transceiver value back to kernel') a regression slipped in. If we have a kernel that does not support the ETHTOOL_xLINKSETTINGS API, then the do_ioctl_glinksettings() function will return a NULL pointer. Hence before memset'ing the pointer to zero we must first check it is valid, as NULL return is perfectly fine when running on old kernels. Fixes: bef780467fa7 ("ioctl: do not pass transceiver value back to kernel") Signed-off-by: Hans-Christian Noren Egtvedt <hegtvedt@cisco.com> --- ethtool.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)