sh: Handle unaligned 16-bit instructions on SH-2A.
This adds some sanity checking in the unaligned instruction handler to
verify the instruction size, which enables basic support for 16-bit
fixups on SH-2A parts.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/kernel/traps_32.c b/arch/sh/kernel/traps_32.c
index 6aba9af..f9760c5 100644
--- a/arch/sh/kernel/traps_32.c
+++ b/arch/sh/kernel/traps_32.c
@@ -452,6 +452,12 @@
u_int rm;
int ret, index;
+ /*
+ * XXX: We can't handle mixed 16/32-bit instructions yet
+ */
+ if (instruction_size(instruction) != 2)
+ return -EINVAL;
+
index = (instruction>>8)&15; /* 0x0F00 */
rm = regs->regs[index];
@@ -619,9 +625,9 @@
se_user += 1;
-#ifndef CONFIG_CPU_SH2A
set_fs(USER_DS);
- if (copy_from_user(&instruction, (u16 *)(regs->pc & ~1), 2)) {
+ if (copy_from_user(&instruction, (insn_size_t *)(regs->pc & ~1),
+ sizeof(instruction))) {
set_fs(oldfs);
goto uspace_segv;
}
@@ -633,7 +639,6 @@
"in \"%s\" pid=%d pc=0x%p ins=0x%04hx\n",
current->comm, current->pid, (void *)regs->pc,
instruction);
-#endif
if (se_usermode & 2)
goto fixup;