perf/arm-cmn: Fix invalid pointer when access dtc object sharing the same IRQ number

[ Upstream commit 4e16f283edc289820e9b2d6f617ed8e514ee8396 ]

When multiple dtcs share the same IRQ number, the irq_friend which
used to refer to dtc object gets calculated incorrect which leads
to invalid pointer.

Fixes: 0ba64770a2 ("perf: Add Arm CMN-600 PMU driver")

Signed-off-by: Tuan Phan <tuanphan@os.amperecomputing.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/1623946129-3290-1-git-send-email-tuanphan@os.amperecomputing.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Tuan Phan 2021-06-17 09:08:49 -07:00 committed by Greg Kroah-Hartman
parent 31dcfec19d
commit e5154bf217

View File

@ -1212,7 +1212,7 @@ static int arm_cmn_init_irqs(struct arm_cmn *cmn)
irq = cmn->dtc[i].irq;
for (j = i; j--; ) {
if (cmn->dtc[j].irq == irq) {
cmn->dtc[j].irq_friend = j - i;
cmn->dtc[j].irq_friend = i - j;
goto next;
}
}