From: Kalderon, Michal <Michal.Kalderon@xxxxxxxxxx> commit 963916fdb3e5ad4af57ac959b5a03bf23f7568ca upstream. Once in_dev_get is called to receive in_device pointer, the in_device reference counter is increased, but if there are no ipv4 addresses configured on the net-device the ifa_list will be null, resulting in a flow that doesn't call in_dev_put to decrease the ref_cnt. This was exposed when running RoCE over ipv6 without any ipv4 addresses configured Fixes: commit 8e3867310c90 ("IB/cma: Fix a race condition in iboe_addr_get_sgid()") Signed-off-by: Michal Kalderon <Michal.Kalderon@xxxxxxxxxx> Signed-off-by: Ariel Elior <Ariel.Elior@xxxxxxxxxx> Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx> Cc: Guenter Roeck <linux@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/rdma/ib_addr.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/include/rdma/ib_addr.h +++ b/include/rdma/ib_addr.h @@ -208,11 +208,13 @@ static inline void iboe_addr_get_sgid(st dev = dev_get_by_index(&init_net, dev_addr->bound_dev_if); if (dev) { ip4 = in_dev_get(dev); - if (ip4 && ip4->ifa_list && ip4->ifa_list->ifa_address) { + if (ip4 && ip4->ifa_list && ip4->ifa_list->ifa_address) ipv6_addr_set_v4mapped(ip4->ifa_list->ifa_address, (struct in6_addr *)gid); + + if (ip4) in_dev_put(ip4); - } + dev_put(dev); } }