qed: fix qed_fill_link() error handling

gcc warns about qed_fill_link possibly accessing uninitialized data:

drivers/net/ethernet/qlogic/qed/qed_main.c: In function 'qed_fill_link':
drivers/net/ethernet/qlogic/qed/qed_main.c:1170:35: error: 'link_caps' may be used uninitialized in this function [-Werror=maybe-uninitialized]

While this warning is only about the specific case of CONFIG_QED_SRIOV
being disabled but the function getting called for a VF (which should
never happen), another possibility is that qed_mcp_get_*() fails without
returning data.

This rearranges the code so we bail out in either of the two cases
and print a warning instead of accessing the uninitialized data.

The qed_link_output structure remains untouched in this case, but
all callers first call memset() on it, so at least we are not leaking
stack data then.

As discussed, we also use a compile-time check to ensure we never
use any of the VF code if CONFIG_QED_SRIOV is disabled, and the
PCI device table is updated to no longer bind to virtual functions
in that configuration.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Arnd Bergmann 2016-06-01 15:29:13 +02:00 committed by David S. Miller
parent bfa49cfc52
commit 14b84e8654
3 changed files with 41 additions and 10 deletions

View File

@ -1105,6 +1105,39 @@ static int qed_get_port_type(u32 media_type)
return port_type;
}
static int qed_get_link_data(struct qed_hwfn *hwfn,
struct qed_mcp_link_params *params,
struct qed_mcp_link_state *link,
struct qed_mcp_link_capabilities *link_caps)
{
void *p;
if (!IS_PF(hwfn->cdev)) {
qed_vf_get_link_params(hwfn, params);
qed_vf_get_link_state(hwfn, link);
qed_vf_get_link_caps(hwfn, link_caps);
return 0;
}
p = qed_mcp_get_link_params(hwfn);
if (!p)
return -ENXIO;
memcpy(params, p, sizeof(*params));
p = qed_mcp_get_link_state(hwfn);
if (!p)
return -ENXIO;
memcpy(link, p, sizeof(*link));
p = qed_mcp_get_link_capabilities(hwfn);
if (!p)
return -ENXIO;
memcpy(link_caps, p, sizeof(*link_caps));
return 0;
}
static void qed_fill_link(struct qed_hwfn *hwfn,
struct qed_link_output *if_link)
{
@ -1116,15 +1149,9 @@ static void qed_fill_link(struct qed_hwfn *hwfn,
memset(if_link, 0, sizeof(*if_link));
/* Prepare source inputs */
if (IS_PF(hwfn->cdev)) {
memcpy(&params, qed_mcp_get_link_params(hwfn), sizeof(params));
memcpy(&link, qed_mcp_get_link_state(hwfn), sizeof(link));
memcpy(&link_caps, qed_mcp_get_link_capabilities(hwfn),
sizeof(link_caps));
} else {
qed_vf_get_link_params(hwfn, &params);
qed_vf_get_link_state(hwfn, &link);
qed_vf_get_link_caps(hwfn, &link_caps);
if (qed_get_link_data(hwfn, &params, &link, &link_caps)) {
dev_warn(&hwfn->cdev->pdev->dev, "no link data available\n");
return;
}
/* Set the link parameters to pass to protocol driver */

View File

@ -12,11 +12,13 @@
#include "qed_vf.h"
#define QED_VF_ARRAY_LENGTH (3)
#ifdef CONFIG_QED_SRIOV
#define IS_VF(cdev) ((cdev)->b_is_vf)
#define IS_PF(cdev) (!((cdev)->b_is_vf))
#ifdef CONFIG_QED_SRIOV
#define IS_PF_SRIOV(p_hwfn) (!!((p_hwfn)->cdev->p_iov_info))
#else
#define IS_VF(cdev) (0)
#define IS_PF(cdev) (1)
#define IS_PF_SRIOV(p_hwfn) (0)
#endif
#define IS_PF_SRIOV_ALLOC(p_hwfn) (!!((p_hwfn)->pf_iov_info))

View File

@ -87,7 +87,9 @@ static const struct pci_device_id qede_pci_tbl[] = {
{PCI_VDEVICE(QLOGIC, PCI_DEVICE_ID_57980S_100), QEDE_PRIVATE_PF},
{PCI_VDEVICE(QLOGIC, PCI_DEVICE_ID_57980S_50), QEDE_PRIVATE_PF},
{PCI_VDEVICE(QLOGIC, PCI_DEVICE_ID_57980S_25), QEDE_PRIVATE_PF},
#ifdef CONFIG_QED_SRIOV
{PCI_VDEVICE(QLOGIC, PCI_DEVICE_ID_57980S_IOV), QEDE_PRIVATE_VF},
#endif
{ 0 }
};