Commit a9018adf authored by Dan Carpenter's avatar Dan Carpenter Committed by Jason Gunthorpe

RDMA/uverbs: Prevent potential underflow

The issue is in drivers/infiniband/core/uverbs_std_types_cq.c in the
UVERBS_HANDLER(UVERBS_METHOD_CQ_CREATE) function.  We check that:

        if (attr.comp_vector >= attrs->ufile->device->num_comp_vectors) {

But we don't check if "attr.comp_vector" is negative.  It could
potentially lead to an array underflow.  My concern would be where
cq->vector is used in the create_cq() function from the cxgb4 driver.

And really "attr.comp_vector" is appears as a u32 to user space so that's
the right type to use.

Fixes: 9ee79fce ("IB/core: Add completion queue (cq) object actions")
Link: https://lore.kernel.org/r/20191011133419.GA22905@mwandaSigned-off-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: default avatarJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@mellanox.com>
parent 777a8b32
...@@ -98,7 +98,7 @@ ib_uverbs_init_udata_buf_or_null(struct ib_udata *udata, ...@@ -98,7 +98,7 @@ ib_uverbs_init_udata_buf_or_null(struct ib_udata *udata,
struct ib_uverbs_device { struct ib_uverbs_device {
atomic_t refcount; atomic_t refcount;
int num_comp_vectors; u32 num_comp_vectors;
struct completion comp; struct completion comp;
struct device dev; struct device dev;
/* First group for device attributes, NULL terminated array */ /* First group for device attributes, NULL terminated array */
......
...@@ -366,7 +366,7 @@ struct ib_tm_caps { ...@@ -366,7 +366,7 @@ struct ib_tm_caps {
struct ib_cq_init_attr { struct ib_cq_init_attr {
unsigned int cqe; unsigned int cqe;
int comp_vector; u32 comp_vector;
u32 flags; u32 flags;
}; };
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment