[PATCH 4.9 040/109] libcxgb: fix error check for ip6_route_output()

From: Greg Kroah-Hartman
Date: Thu Dec 07 2017 - 08:00:02 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Varun Prakash <varun@xxxxxxxxxxx>


[ Upstream commit a9a8cdb368d99bb655b5cdabea560446db0527cc ]

ip6_route_output() never returns NULL so
check dst->error instead of !dst.

Signed-off-by: Varun Prakash <varun@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/chelsio/libcxgb/libcxgb_cm.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)

--- a/drivers/net/ethernet/chelsio/libcxgb/libcxgb_cm.c
+++ b/drivers/net/ethernet/chelsio/libcxgb/libcxgb_cm.c
@@ -133,17 +133,15 @@ cxgb_find_route6(struct cxgb4_lld_info *
if (ipv6_addr_type(&fl6.daddr) & IPV6_ADDR_LINKLOCAL)
fl6.flowi6_oif = sin6_scope_id;
dst = ip6_route_output(&init_net, NULL, &fl6);
- if (!dst)
- goto out;
- if (!cxgb_our_interface(lldi, get_real_dev,
- ip6_dst_idev(dst)->dev) &&
- !(ip6_dst_idev(dst)->dev->flags & IFF_LOOPBACK)) {
+ if (dst->error ||
+ (!cxgb_our_interface(lldi, get_real_dev,
+ ip6_dst_idev(dst)->dev) &&
+ !(ip6_dst_idev(dst)->dev->flags & IFF_LOOPBACK))) {
dst_release(dst);
- dst = NULL;
+ return NULL;
}
}

-out:
return dst;
}
EXPORT_SYMBOL(cxgb_find_route6);