MIPS: KASLR: Correct valid bits in apply_r_mips_26_rel()

Apply_r_mips_26_rel() relocates instructions like j, jal and etc. These
instructions consist of 6bits function field and 26bits address field.
The value of target_addr as follows,
=================================================================
|     high 4bits           |            low 28bits              |
=================================================================
|the high 4bits of this PC | the low 26bits of instructions << 2|
=================================================================
Thus, loc_orig and log_new both need high 4bits rather than high 6bits.

Signed-off-by: Jinyang He <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

Author: MQ-mengqing

arch/mips/kernel/relocate.c

@@ -95,7 +95,7 @@ static int __init apply_r_mips_26_rel(u32 *loc_orig, u32 *loc_new, long offset)
 
 	/* Original target address */
 	target_addr <<= 2;
-	target_addr += (unsigned long)loc_orig & ~0x03ffffff;
+	target_addr += (unsigned long)loc_orig & 0xf0000000;
 
 	/* Get the new target address */
 	target_addr += offset;
@@ -105,7 +105,7 @@ static int __init apply_r_mips_26_rel(u32 *loc_orig, u32 *loc_new, long offset)
 		return -ENOEXEC;
 	}
 
-	target_addr -= (unsigned long)loc_new & ~0x03ffffff;
+	target_addr -= (unsigned long)loc_new & 0xf0000000;
 	target_addr >>= 2;
 
 	*loc_new = (*loc_new & ~0x03ffffff) | (target_addr & 0x03ffffff);