8 files changed, 25 insertions, 16 deletions

diff --git a/liblzma/simple/arm.c b/liblzma/simple/arm.c
index 181d0e3..ff5073a 100644
--- a/liblzma/simple/arm.c
+++ b/liblzma/simple/arm.c
@@ -22,9 +22,9 @@ arm_code(void *simple lzma_attribute((__unused__)),
 	size_t i;
 	for (i = 0; i + 4 <= size; i += 4) {
 		if (buffer[i + 3] == 0xEB) {
-			uint32_t src = (buffer[i + 2] << 16)
-					| (buffer[i + 1] << 8)
-					| (buffer[i + 0]);
+			uint32_t src = ((uint32_t)(buffer[i + 2]) << 16)
+					| ((uint32_t)(buffer[i + 1]) << 8)
+					| (uint32_t)(buffer[i + 0]);
 			src <<= 2;
 
 			uint32_t dest;
diff --git a/liblzma/simple/armthumb.c b/liblzma/simple/armthumb.c
index eab4862..a8da334 100644
--- a/liblzma/simple/armthumb.c
+++ b/liblzma/simple/armthumb.c
@@ -23,10 +23,10 @@ armthumb_code(void *simple lzma_attribute((__unused__)),
 	for (i = 0; i + 4 <= size; i += 2) {
 		if ((buffer[i + 1] & 0xF8) == 0xF0
 				&& (buffer[i + 3] & 0xF8) == 0xF8) {
-			uint32_t src = ((buffer[i + 1] & 0x7) << 19)
-					| (buffer[i + 0] << 11)
-					| ((buffer[i + 3] & 0x7) << 8)
-					| (buffer[i + 2]);
+			uint32_t src = (((uint32_t)(buffer[i + 1]) & 7) << 19)
+				| ((uint32_t)(buffer[i + 0]) << 11)
+				| (((uint32_t)(buffer[i + 3]) & 7) << 8)
+				| (uint32_t)(buffer[i + 2]);
 
 			src <<= 1;
 
diff --git a/liblzma/simple/ia64.c b/liblzma/simple/ia64.c
index 580529e..6492d0a 100644
--- a/liblzma/simple/ia64.c
+++ b/liblzma/simple/ia64.c
@@ -70,7 +70,7 @@ ia64_code(void *simple lzma_attribute((__unused__)),
 				inst_norm |= (uint64_t)(dest & 0x100000)
 						<< (36 - 20);
 
-				instruction &= (1 << bit_res) - 1;
+				instruction &= (1U << bit_res) - 1;
 				instruction |= (inst_norm << bit_res);
 
 				for (size_t j = 0; j < 6; j++)
diff --git a/liblzma/simple/powerpc.c b/liblzma/simple/powerpc.c
index 54dfbf1..0b60e9b 100644
--- a/liblzma/simple/powerpc.c
+++ b/liblzma/simple/powerpc.c
@@ -25,10 +25,11 @@ powerpc_code(void *simple lzma_attribute((__unused__)),
 		if ((buffer[i] >> 2) == 0x12
 				&& ((buffer[i + 3] & 3) == 1)) {
 
-			const uint32_t src = ((buffer[i + 0] & 3) << 24)
-					| (buffer[i + 1] << 16)
-					| (buffer[i + 2] << 8)
-					| (buffer[i + 3] & (~3));
+			const uint32_t src
+				= (((uint32_t)(buffer[i + 0]) & 3) << 24)
+				| ((uint32_t)(buffer[i + 1]) << 16)
+				| ((uint32_t)(buffer[i + 2]) << 8)
+				| ((uint32_t)(buffer[i + 3]) & ~UINT32_C(3));
 
 			uint32_t dest;
 			if (is_encoder)
diff --git a/liblzma/simple/simple_coder.c b/liblzma/simple/simple_coder.c
index 13ebabc..4f499be 100644
--- a/liblzma/simple/simple_coder.c
+++ b/liblzma/simple/simple_coder.c
@@ -118,7 +118,15 @@ simple_code(void *coder_ptr, const lzma_allocator *allocator,
 		// coder->pos and coder->size yet. This way the coder can be
 		// restarted if the next filter in the chain returns e.g.
 		// LZMA_MEM_ERROR.
-		memcpy(out + *out_pos, coder->buffer + coder->pos, buf_avail);
+		//
+		// Do the memcpy() conditionally because out can be NULL
+		// (in which case buf_avail is always 0). Calling memcpy()
+		// with a null-pointer is undefined even if the third
+		// argument is 0.
+		if (buf_avail > 0)
+			memcpy(out + *out_pos, coder->buffer + coder->pos,
+					buf_avail);
+
 		*out_pos += buf_avail;
 
 		// Copy/Encode/Decode more data to out[].
diff --git a/liblzma/simple/simple_decoder.c b/liblzma/simple/simple_decoder.c
index 1d864f2..dc4d241 100644
--- a/liblzma/simple/simple_decoder.c
+++ b/liblzma/simple/simple_decoder.c
@@ -28,7 +28,7 @@ lzma_simple_props_decode(void **options, const lzma_allocator *allocator,
 	if (opt == NULL)
 		return LZMA_MEM_ERROR;
 
-	opt->start_offset = unaligned_read32le(props);
+	opt->start_offset = read32le(props);
 
 	// Don't leave an options structure allocated if start_offset is zero.
 	if (opt->start_offset == 0)
diff --git a/liblzma/simple/simple_encoder.c b/liblzma/simple/simple_encoder.c
index 8aa463b..d2cc03e 100644
--- a/liblzma/simple/simple_encoder.c
+++ b/liblzma/simple/simple_encoder.c
@@ -32,7 +32,7 @@ lzma_simple_props_encode(const void *options, uint8_t *out)
 	if (opt == NULL || opt->start_offset == 0)
 		return LZMA_OK;
 
-	unaligned_write32le(out, opt->start_offset);
+	write32le(out, opt->start_offset);
 
 	return LZMA_OK;
 }
diff --git a/liblzma/simple/x86.c b/liblzma/simple/x86.c
index 0b14807..0e78909 100644
--- a/liblzma/simple/x86.c
+++ b/liblzma/simple/x86.c
@@ -97,7 +97,7 @@ x86_code(void *simple_ptr, uint32_t now_pos, bool is_encoder,
 				if (!Test86MSByte(b))
 					break;
 
-				src = dest ^ ((1 << (32 - i * 8)) - 1);
+				src = dest ^ ((1U << (32 - i * 8)) - 1);
 			}
 
 			buffer[buffer_pos + 4]