The patch below does not apply to the 4.17-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From fe48aecb4df837540f13b5216f27ddb306aaf4b9 Mon Sep 17 00:00:00 2001
From: Leon Romanovsky leonro@mellanox.com Date: Sun, 1 Jul 2018 15:31:54 +0300 Subject: [PATCH] RDMA/uverbs: Don't fail in creation of multiple flows
The conversion from offsetof() calculations to sizeof() wrongly behaved for missed exact size and in scenario with more than one flow.
In such scenario we got "create flow failed, flow 10: 8 bytes left from uverb cmd" error, which is wrong because the size of kern_spec is exactly 8 bytes, and we were not supposed to fail.
Cc: stable@vger.kernel.org # 3.12 Fixes: 4fae7f170416 ("RDMA/uverbs: Fix slab-out-of-bounds in ib_uverbs_ex_create_flow") Reported-by: Ran Rozenstein ranro@mellanox.com Signed-off-by: Leon Romanovsky leonro@mellanox.com Signed-off-by: Jason Gunthorpe jgg@mellanox.com
diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c index 87ffeebc0b28..cc06e8404e9b 100644 --- a/drivers/infiniband/core/uverbs_cmd.c +++ b/drivers/infiniband/core/uverbs_cmd.c @@ -3586,7 +3586,7 @@ int ib_uverbs_ex_create_flow(struct ib_uverbs_file *file, kern_spec = kern_flow_attr->flow_specs; ib_spec = flow_attr + 1; for (i = 0; i < flow_attr->num_of_specs && - cmd.flow_attr.size > sizeof(*kern_spec) && + cmd.flow_attr.size >= sizeof(*kern_spec) && cmd.flow_attr.size >= kern_spec->size; i++) { err = kern_spec_to_ib_spec(