In the page fault handler, an access to user-space memory
without get/put_user() or copy_from/to_user() routines is
not resolved properly. Like arm and other architectures,
we need to let it die earlier in page fault handler.
Signed-off-by: Eric Lin <tesh...@andestech.com>
Cc: Alan Kao <alan...@andestech.com>
---
arch/riscv/mm/fault.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
index 3c8b9e433c67..a452cfa266a2 100644
--- a/arch/riscv/mm/fault.c
+++ b/arch/riscv/mm/fault.c
@@ -232,6 +232,9 @@ asmlinkage void do_page_fault(struct pt_regs *regs)
if (user_mode(regs))
flags |= FAULT_FLAG_USER;
+ if (!user_mode(regs) && addr < TASK_SIZE && unlikely(!(regs->status &
SR_SUM)))
+ die(regs, "Accessing user space memory without uaccess
routines\n");
+
perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr);
if (cause == EXC_STORE_PAGE_FAULT)
--
2.17.0
