Commit e537deec authored by Leon Romanovsky's avatar Leon Romanovsky
Browse files

RDMA/mana_ib: Add flex array to struct mana_cfg_rx_steer_req_v2 

The "struct mana_cfg_rx_steer_req_v2" uses a dynamically sized set of
trailing elements. Specifically, it uses a "mana_handle_t" array. So,
use the preferred way in the kernel declaring a flexible array [1].

At the same time, prepare for the coming implementation by GCC and Clang
of the __counted_by attribute. Flexible array members annotated with
__counted_by can have their accesses bounds-checked at run-time via
CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for
strcpy/memcpy-family functions).

Also, avoid the open-coded arithmetic in the memory allocator functions
[2] using the "struct_size" macro.

Moreover, use the "offsetof" helper to get the indirect table offset
instead of the "sizeof" operator and avoid the open-coded arithmetic in
pointers using the new flex member. This new structure member also allow
us to remove the "req_indir_tab" variable since it is no longer needed.

Now, it is also possible to use the "flex_array_size" helper to compute
the size of these trailing elements in the "memcpy" function.

Specifically, the first commit adds the flex member and the patches 2
and 3 refactor the consumers of the "struct mana_cfg_rx_steer_req_v2".

This code was detected with the help of Coccinelle, and audited and
modified manually. The Coccinelle script used to detect this code
pattern is the following:

virtual report

@rule1@
type t1;
type t2;
identifier i0;
identifier i1;
identifier i2;
identifier ALLOC =~
"kmalloc|kzalloc|kmalloc_node|kzalloc_node|vmalloc|vzalloc|kvmalloc|kvzalloc";
position p1;
@@

i0 = sizeof(t1) + sizeof(t2) * i1;
...
i2 = ALLOC@p1(..., i0, ...);

@script:python depends on report@
p1 << rule1.p1;
@@

msg = "WARNING: verify allocation on line %s" % (p1[0].line)
coccilib.report.print_report(p1[0],msg)

[1] https://www.kernel.org/doc/html/next/process/deprecated.html#zero-length-and-one-element-arrays
[2] https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments
Link: https://lore.kernel.org/all/AS8PR02MB72374BD1B23728F2E3C3B1A18B022@AS8PR02MB7237.eurprd02.prod.outlook.com


Signed-off-by: default avatarErick Archer <erick.archer@outlook.com>
Signed-off-by: default avatarLeon Romanovsky <leon@kernel.org>

* mana-ib-flex:
  net: mana: Avoid open coded arithmetic
  RDMA/mana_ib: Prefer struct_size over open coded arithmetic
  net: mana: Add flex array to struct mana_cfg_rx_steer_req_v2
parents ee20cc17 a68292eb

drivers/infiniband/hw/mana/qp.c

+5 −7
Original line number Diff line number Diff line
@@ -15,15 +15,13 @@ static int mana_ib_cfg_vport_steering(struct mana_ib_dev *dev, 
	struct mana_port_context *mpc = netdev_priv(ndev);

	struct mana_cfg_rx_steer_req_v2 *req;

	struct mana_cfg_rx_steer_resp resp = {};

	mana_handle_t *req_indir_tab;

	struct gdma_context *gc;

	u32 req_buf_size;

	int i, err;



	gc = mdev_to_gc(dev);



	req_buf_size =

		sizeof(*req) + sizeof(mana_handle_t) * MANA_INDIRECT_TABLE_SIZE;

	req_buf_size = struct_size(req, indir_tab, MANA_INDIRECT_TABLE_SIZE);

	req = kzalloc(req_buf_size, GFP_KERNEL);

	if (!req)

		return -ENOMEM;
@@ -44,20 +42,20 @@ static int mana_ib_cfg_vport_steering(struct mana_ib_dev *dev, 
		req->rss_enable = true;



	req->num_indir_entries = MANA_INDIRECT_TABLE_SIZE;

	req->indir_tab_offset = sizeof(*req);

	req->indir_tab_offset = offsetof(struct mana_cfg_rx_steer_req_v2,

					 indir_tab);

	req->update_indir_tab = true;

	req->cqe_coalescing_enable = 1;



	req_indir_tab = (mana_handle_t *)(req + 1);

	/* The ind table passed to the hardware must have

	 * MANA_INDIRECT_TABLE_SIZE entries. Adjust the verb

	 * ind_table to MANA_INDIRECT_TABLE_SIZE if required

	 */

	ibdev_dbg(&dev->ib_dev, "ind table size %u\n", 1 << log_ind_tbl_size);

	for (i = 0; i < MANA_INDIRECT_TABLE_SIZE; i++) {

		req_indir_tab[i] = ind_table[i % (1 << log_ind_tbl_size)];

		req->indir_tab[i] = ind_table[i % (1 << log_ind_tbl_size)];

		ibdev_dbg(&dev->ib_dev, "index %u handle 0x%llx\n", i,

			  req_indir_tab[i]);

			  req->indir_tab[i]);

	}



	req->update_hashkey = true;

drivers/net/ethernet/microsoft/mana/mana_en.c

+6 −8
Original line number Diff line number Diff line
@@ -1058,11 +1058,10 @@ static int mana_cfg_vport_steering(struct mana_port_context *apc, 
	struct mana_cfg_rx_steer_req_v2 *req;

	struct mana_cfg_rx_steer_resp resp = {};

	struct net_device *ndev = apc->ndev;

	mana_handle_t *req_indir_tab;

	u32 req_buf_size;

	int err;



	req_buf_size = sizeof(*req) + sizeof(mana_handle_t) * num_entries;

	req_buf_size = struct_size(req, indir_tab, num_entries);

	req = kzalloc(req_buf_size, GFP_KERNEL);

	if (!req)

		return -ENOMEM;
@@ -1074,7 +1073,8 @@ static int mana_cfg_vport_steering(struct mana_port_context *apc, 


	req->vport = apc->port_handle;

	req->num_indir_entries = num_entries;

	req->indir_tab_offset = sizeof(*req);

	req->indir_tab_offset = offsetof(struct mana_cfg_rx_steer_req_v2,

					 indir_tab);

	req->rx_enable = rx;

	req->rss_enable = apc->rss_state;

	req->update_default_rxobj = update_default_rxobj;
@@ -1086,11 +1086,9 @@ static int mana_cfg_vport_steering(struct mana_port_context *apc, 
	if (update_key)

		memcpy(&req->hashkey, apc->hashkey, MANA_HASH_KEY_SIZE);



	if (update_tab) {

		req_indir_tab = (mana_handle_t *)(req + 1);

		memcpy(req_indir_tab, apc->rxobj_table,

		       req->num_indir_entries * sizeof(mana_handle_t));

	}

	if (update_tab)

		memcpy(req->indir_tab, apc->rxobj_table,

		       flex_array_size(req, indir_tab, req->num_indir_entries));



	err = mana_send_request(apc->ac, req, req_buf_size, &resp,

				sizeof(resp));

include/net/mana/mana.h

+1 −0
Original line number Diff line number Diff line
@@ -671,6 +671,7 @@ struct mana_cfg_rx_steer_req_v2 { 
	u8 hashkey[MANA_HASH_KEY_SIZE];

	u8 cqe_coalescing_enable;

	u8 reserved2[7];

	mana_handle_t indir_tab[] __counted_by(num_indir_entries);

}; /* HW DATA */



struct mana_cfg_rx_steer_resp {