[PATCH AUTOSEL 4.9 23/38] gtp: avoid zero size hashtable

From: Taehee Yoo &lt;ap420073(a)gmail.com&gt; [ Upstream commit 6a902c0f31993ab02e1b6ea7085002b9c9083b6a ] GTP default hashtable size is 1024 and userspace could set specific hashtable size with IFLA_GTP_PDP_HASHSIZE. If hashtable size is set to 0 from userspace, hashtable will not work and panic will occur. Fixes: 459aa660eb1d ("gtp: add initial driver for datapath of GPRS Tunneling Protocol (GTP-U)") Signed-off-by: Taehee Yoo &lt;ap420073(a)gmail.com&gt; Signed-off-by: Jakub Kicinski &lt;jakub.kicinski(a)netronome.com&gt; Signed-off-by: Sasha Levin &lt;sashal(a)kernel.org&gt; --- drivers/net/gtp.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c index 1d2fc81dc714..c2898718b593 100644 --- a/drivers/net/gtp.c +++ b/drivers/net/gtp.c @@ -677,10 +677,13 @@ static int gtp_newlink(struct net *src_net, struct net_device *dev, if (err < 0) goto out_err; - if (!data[IFLA_GTP_PDP_HASHSIZE]) + if (!data[IFLA_GTP_PDP_HASHSIZE]) { hashsize = 1024; - else + } else { hashsize = nla_get_u32(data[IFLA_GTP_PDP_HASHSIZE]); + if (!hashsize) + hashsize = 1024; + } err = gtp_hashtable_new(gtp, hashsize); if (err < 0) -- 2.20.1