spmi: spmi-pmic-arb: block access for invalid PMIC arbiter v5 SPMI writes

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.

Change-Id: If601a8c737f10be2a7d1e894f7285cf0de4eb4a5
Signed-off-by: David Collins <collinsd@codeaurora.org>
This commit is contained in:
David Collins 2018-01-22 14:54:04 -08:00 committed by David Collins
parent 76bbd30e3d
commit 09b1daa2d5

View File

@ -1125,6 +1125,11 @@ 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;
}