From 6f329d9da2a5ae032fcde800a99b118124ed5270 Mon Sep 17 00:00:00 2001
From: Claudiu Manoil <claudiu.manoil@nxp.com>
Date: Fri, 17 Sep 2021 13:22:05 +0300
Subject: [PATCH] enetc: Fix illegal access when reading affinity_hint
Git-commit: 7237a494decfa17d0b9d0076e6cee3235719de90
Patch-mainline: v5.15-rc3
References: stable-5.14.9
[ Upstream commit 7237a494decfa17d0b9d0076e6cee3235719de90 ]
irq_set_affinity_hit() stores a reference to the cpumask_t
parameter in the irq descriptor, and that reference can be
accessed later from irq_affinity_hint_proc_show(). Since
the cpu_mask parameter passed to irq_set_affinity_hit() has
only temporary storage (it's on the stack memory), later
accesses to it are illegal. Thus reads from the corresponding
procfs affinity_hint file can result in paging request oops.
The issue is fixed by the get_cpu_mask() helper, which provides
a permanent storage for the cpumask_t parameter.
Fixes: d4fd0404c1c9 ("enetc: Introduce basic PF and VF ENETC ethernet drivers")
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/net/ethernet/freescale/enetc/enetc.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c
index 3ca93adb9662..7f90c27c0e79 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc.c
@@ -1879,7 +1879,6 @@ static void enetc_clear_bdrs(struct enetc_ndev_priv *priv)
static int enetc_setup_irqs(struct enetc_ndev_priv *priv)
{
struct pci_dev *pdev = priv->si->pdev;
- cpumask_t cpu_mask;
int i, j, err;
for (i = 0; i < priv->bdr_int_num; i++) {
@@ -1908,9 +1907,7 @@ static int enetc_setup_irqs(struct enetc_ndev_priv *priv)
enetc_wr(hw, ENETC_SIMSITRV(idx), entry);
}
- cpumask_clear(&cpu_mask);
- cpumask_set_cpu(i % num_online_cpus(), &cpu_mask);
- irq_set_affinity_hint(irq, &cpu_mask);
+ irq_set_affinity_hint(irq, get_cpu_mask(i % num_online_cpus()));
}
return 0;
--
2.26.2