arm64: module: ensure instruction is little-endian before manipulation

Relocations that require an instruction immediate to be re-encoded must
ensure that the instruction pattern is represented in a little-endian
format for the manipulation code to work correctly.

This patch converts the loaded instruction into native-endianess prior
to encoding and then converts back to little-endian byteorder before
updating memory.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Tested-by: Matthew Leach <matthew.leach@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c
index ca0e3d55da998fe5b302530bad487f52a7127938..2c28a6cf93e610a9484442f662c5975a180b7790 100644 (file)
--- a/arch/arm64/kernel/module.c
+++ b/arch/arm64/kernel/module.c
@@ -111,6 +111,9 @@ static u32 encode_insn_immediate(enum aarch64_imm_type type, u32 insn, u64 imm)
        u32 immlo, immhi, lomask, himask, mask;
        int shift;
 
+       /* The instruction stream is always little endian. */
+       insn = le32_to_cpu(insn);
+
        switch (type) {
        case INSN_IMM_MOVNZ:
                /*
@@ -179,7 +182,7 @@ static u32 encode_insn_immediate(enum aarch64_imm_type type, u32 insn, u64 imm)
        insn &= ~(mask << shift);
        insn |= (imm & mask) << shift;
 
-       return insn;
+       return cpu_to_le32(insn);
 }
 
 static int reloc_insn_movw(enum aarch64_reloc_op op, void *place, u64 val,