From: Ido Kalir <idok@xxxxxxxxxxxx> If QP is not visible to the pid, then we try to decrease its reference count and return from the function before the QP pointer is initialized. This lead to NULL pointer dereference. Fix it by pass directly the res to the rdma_restract_put as arg instead of &qp->res. This fixes below call trace: [ 5845.110329] BUG: kernel NULL pointer dereference, address: 00000000000000dc [ 5845.120482] Oops: 0002 [#1] SMP PTI [ 5845.129119] RIP: 0010:rdma_restrack_put+0x5/0x30 [ib_core] [ 5845.169450] Call Trace: [ 5845.170544] rdma_counter_get_qp+0x5c/0x70 [ib_core] [ 5845.172074] rdma_counter_bind_qpn_alloc+0x6f/0x1a0 [ib_core] [ 5845.173731] nldev_stat_set_doit+0x314/0x330 [ib_core] [ 5845.175279] rdma_nl_rcv_msg+0xeb/0x1d0 [ib_core] [ 5845.176772] ? __kmalloc_node_track_caller+0x20b/0x2b0 [ 5845.178321] rdma_nl_rcv+0xcb/0x120 [ib_core] [ 5845.179753] netlink_unicast+0x179/0x220 [ 5845.181066] netlink_sendmsg+0x2d8/0x3d0 [ 5845.182338] sock_sendmsg+0x30/0x40 [ 5845.183544] __sys_sendto+0xdc/0x160 [ 5845.184832] ? syscall_trace_enter+0x1f8/0x2e0 [ 5845.186209] ? __audit_syscall_exit+0x1d9/0x280 [ 5845.187584] __x64_sys_sendto+0x24/0x30 [ 5845.188867] do_syscall_64+0x48/0x120 [ 5845.190097] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 1bd8e0a9d0fd1 ("RDMA/counter: Allow manual mode configuration support") Signed-off-by: Ido Kalir <idok@xxxxxxxxxxxx> Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx> --- drivers/infiniband/core/counters.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/infiniband/core/counters.c b/drivers/infiniband/core/counters.c index b79890739a2c..955d061af06a 100644 --- a/drivers/infiniband/core/counters.c +++ b/drivers/infiniband/core/counters.c @@ -424,7 +424,7 @@ static struct ib_qp *rdma_counter_get_qp(struct ib_device *dev, u32 qp_num) return qp; err: - rdma_restrack_put(&qp->res); + rdma_restrack_put(res); return NULL; } -- 2.20.1