在 2022/4/12 21:08, Kefeng Wang 写道:
[...]
+
+bool fixup_exception_mc(struct pt_regs *regs)
+{
+ const struct exception_table_entry *ex;
+
+ ex = search_exception_tables(instruction_pointer(regs));
+ if (!ex)
+ return false;
+
+ switch (ex->type) {
+ case EX_TYPE_UACCESS_MC:
+ return ex_handler_fixup(ex, regs);
+ }
+
+ return false;
+}
The definition of EX_TYPE_UACCESS_MC is in patch4, please fix it, and if
arm64 exception table
ok, will do next version.
is sorted by exception type, we could drop fixup_exception_mc(), right?
In sort_relative_table_with_data(), it seems sorted by insn and data.
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 77341b160aca..56b13cf8bf1d 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -695,6 +695,30 @@ static int do_bad(unsigned long far, unsigned int
esr, struct pt_regs *regs)
return 1; /* "fault" */
}
+static bool arm64_process_kernel_sea(unsigned long addr, unsigned int
esr,
+ struct pt_regs *regs, int sig, int code)
+{
+ if (!IS_ENABLED(CONFIG_ARCH_HAS_COPY_MC))
+ return false;
+
+ if (user_mode(regs) || !current->mm)
+ return false;
+
+ if (apei_claim_sea(regs) < 0)
+ return false;
+
+ current->thread.fault_address = 0;
+ current->thread.fault_code = esr;
+
Use set_thread_esr(0, esr) and move it after fixup_exception_mc();
+ if (!fixup_exception_mc(regs))
+ return false;
+
+ arm64_force_sig_fault(sig, code, addr,
+ "Uncorrected hardware memory error in kernel-access\n");
+
+ return true;
+}
+
static int do_sea(unsigned long far, unsigned int esr, struct
pt_regs *regs)
{
const struct fault_info *inf;
@@ -720,6 +744,10 @@ static int do_sea(unsigned long far, unsigned int
esr, struct pt_regs *regs)
*/
siaddr = untagged_addr(far);
}
+
+ if (arm64_process_kernel_sea(siaddr, esr, regs, inf->sig,
inf->code))
+ return 0;
+
Rename arm64_process_kernel_sea() to arm64_do_kernel_sea()
if (!arm64_do_kernel_sea())
arm64_notify_die();
Agreed, will do next version.
arm64_notify_die(inf->name, regs, inf->sig, inf->code, siaddr,
esr);
return 0;
diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h
index 546179418ffa..dd952aeecdc1 100644
--- a/include/linux/uaccess.h
+++ b/include/linux/uaccess.h
@@ -174,6 +174,14 @@ copy_mc_to_kernel(void *dst, const void *src,
size_t cnt)
}
#endif
+#ifndef copy_mc_to_user
+static inline unsigned long __must_check
+copy_mc_to_user(void *dst, const void *src, size_t cnt)
+{
Add check_object_size(cnt, src, true); which could make
HARDENED_USERCOPY works.
Agreed, will do next version.
Thanks KeFeng,
Tong.
+ return raw_copy_to_user(dst, src, cnt);
+}
+#endif
+
static __always_inline void pagefault_disabled_inc(void)
{
current->pagefault_disabled++;
.
