| Message ID | 20190517164746.110786-6-swboyd@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Read-only memremap() proposal | expand |
diff --git a/drivers/soc/qcom/cmd-db.c b/drivers/soc/qcom/cmd-db.c index 10a34d26b753..6365e8260282 100644 --- a/drivers/soc/qcom/cmd-db.c +++ b/drivers/soc/qcom/cmd-db.c @@ -240,7 +240,8 @@ static int cmd_db_dev_probe(struct platform_device *pdev) { int ret = 0; - cmd_db_header = devm_memremap_reserved_mem(&pdev->dev, MEMREMAP_WB); + cmd_db_header = devm_memremap_reserved_mem(&pdev->dev, + MEMREMAP_RO | MEMREMAP_WB); if (IS_ERR(cmd_db_header)) { ret = PTR_ERR(cmd_db_header); cmd_db_header = NULL;
The command DB is read-only already to the kernel because everything is const marked once we map it. Let's go one step further and try to map the memory as read-only in the page tables. This should make it harder for random code to corrupt the database and change the contents. Cc: Evan Green <evgreen@chromium.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Andy Gross <agross@kernel.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Stephen Boyd <swboyd@chromium.org> --- drivers/soc/qcom/cmd-db.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)