ARM: 7939/1: traps: fix opcode endianness when read from user memory
authorTaras Kondratiuk <taras.kondratiuk@linaro.org>
Fri, 10 Jan 2014 00:36:00 +0000 (01:36 +0100)
committerRussell King <rmk+kernel@arm.linux.org.uk>
Sat, 11 Jan 2014 12:06:59 +0000 (12:06 +0000)
Currently code has an inverted logic: opcode from user memory
is swapped to a proper endianness only in case of read error.
While normally opcode should be swapped only if it was read
correctly from user memory.

Reviewed-by: Victor Kamensky <victor.kamensky@linaro.org>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/arm/kernel/traps.c

index 6eda3bf85c52123dc75fb04fe46f0eb197c78d62..4636d56af2db63f64703b7417a551d78dffecbe0 100644 (file)
@@ -431,9 +431,10 @@ asmlinkage void __exception do_undefinstr(struct pt_regs *regs)
                        instr2 = __mem_to_opcode_thumb16(instr2);
                        instr = __opcode_thumb32_compose(instr, instr2);
                }
-       } else if (get_user(instr, (u32 __user *)pc)) {
+       } else {
+               if (get_user(instr, (u32 __user *)pc))
+                       goto die_sig;
                instr = __mem_to_opcode_arm(instr);
-               goto die_sig;
        }
 
        if (call_undef_hook(regs, instr) == 0)