From 32e6aea33944f364d51cd263e4cd236393a188b6 Mon Sep 17 00:00:00 2001 From: Douglas Miller Date: Fri, 20 May 2022 14:37:06 -0400 Subject: [PATCH] RDMA/hfi1: Prevent panic when SDMA is disabled [ Upstream commit 629e052d0c98e46dde9f0824f0aa437f678d9b8f ] If the hfi1 module is loaded with HFI1_CAP_SDMA off, a call to hfi1_write_iter() will dereference a NULL pointer and panic. A typical stack frame is: sdma_select_user_engine [hfi1] hfi1_user_sdma_process_request [hfi1] hfi1_write_iter [hfi1] do_iter_readv_writev do_iter_write vfs_writev do_writev do_syscall_64 The fix is to test for SDMA in hfi1_write_iter() and fail the I/O with EINVAL. Link: https://lore.kernel.org/r/20220520183706.48973.79803.stgit@awfm-01.cornelisnetworks.com Signed-off-by: Douglas Miller Signed-off-by: Dennis Dalessandro Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin --- drivers/infiniband/hw/hfi1/file_ops.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/infiniband/hw/hfi1/file_ops.c b/drivers/infiniband/hw/hfi1/file_ops.c index 1783a6e..3ebdd42 100644 --- a/drivers/infiniband/hw/hfi1/file_ops.c +++ b/drivers/infiniband/hw/hfi1/file_ops.c @@ -265,6 +265,8 @@ static ssize_t hfi1_write_iter(struct kiocb *kiocb, struct iov_iter *from) unsigned long dim = from->nr_segs; int idx; + if (!HFI1_CAP_IS_KSET(SDMA)) + return -EINVAL; idx = srcu_read_lock(&fd->pq_srcu); pq = srcu_dereference(fd->pq, &fd->pq_srcu); if (!cq || !pq) { -- 2.7.4