2022-06-12 13:51:02

by Fenglin Wu

Subject: [RESEND PATCH v6 07/10] spmi: pmic-arb: block access for invalid PMIC arbiter v5 SPMI writes

From: David Collins <[email protected]>

The system crashes due to an access permission violation when
writing to a PMIC peripheral which is not owned by the current
ee. Add a check for PMIC arbiter version 5 for such invalid
write requests and return an error instead of crashing the
system.

Signed-off-by: David Collins <[email protected]>
Signed-off-by: Fenglin Wu <[email protected]>
---
drivers/spmi/spmi-pmic-arb.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/spmi/spmi-pmic-arb.c b/drivers/spmi/spmi-pmic-arb.c
index cf92abc..39f25bc 100644
--- a/drivers/spmi/spmi-pmic-arb.c
+++ b/drivers/spmi/spmi-pmic-arb.c
@@ -1133,6 +1133,11 @@ static int pmic_arb_offset_v5(struct spmi_pmic_arb *pmic_arb, u8 sid, u16 addr,
offset = 0x10000 * pmic_arb->ee + 0x80 * apid;
break;
case PMIC_ARB_CHANNEL_RW:
+ if (pmic_arb->apid_data[apid].write_ee != pmic_arb->ee) {
+ dev_err(&pmic_arb->spmic->dev, "disallowed SPMI write to sid=%u, addr=0x%04X\n",
+ sid, addr);
+ return -EPERM;
+ }
offset = 0x10000 * apid;
break;
}
--
2.7.4

2022-08-31 17:49:32

by Stephen Boyd

Subject: Re: [RESEND PATCH v6 07/10] spmi: pmic-arb: block access for invalid PMIC arbiter v5 SPMI writes

Quoting Fenglin Wu (2022-06-11 20:24:43)
> From: David Collins <[email protected]>
>
> The system crashes due to an access permission violation when
> writing to a PMIC peripheral which is not owned by the current
> ee. Add a check for PMIC arbiter version 5 for such invalid
> write requests and return an error instead of crashing the
> system.
>
> Signed-off-by: David Collins <[email protected]>
> Signed-off-by: Fenglin Wu <[email protected]>
> ---

Applied to spmi-next