diff --git a/CHANGES b/CHANGES
index f1f2c7469..515b9c4e4 100644
--- a/CHANGES
+++ b/CHANGES
@@ -11,6 +11,7 @@ Bugfixes:
  - Qt: Fix locale being set to English on settings save (fixes mgba.io/i/906)
  - LR35902: Fix watchpoints not reporting new value
  - GBA Audio: Increase PSG volume (fixes mgba.io/i/932)
+ - GBA BIOS: Fix incorrect exit condition in LZ77
 Misc:
  - GBA: Improve multiboot image detection
  - GB MBC: Remove erroneous bank 0 wrapping
diff --git a/src/gba/bios.c b/src/gba/bios.c
index 65014898e..a7c2a80b0 100644
--- a/src/gba/bios.c
+++ b/src/gba/bios.c
@@ -529,8 +529,10 @@ static void _unLz77(struct GBA* gba, int width) {
 				source += 2;
 				disp = dest - (block & 0x0FFF) - 1;
 				bytes = (block >> 12) + 3;
-				while (bytes-- && remaining) {
-					--remaining;
+				while (bytes--) {
+					if (remaining) {
+						--remaining;
+					}
 					if (width == 2) {
 						byte = (int16_t) cpu->memory.load16(cpu, disp & ~1, 0);
 						if (dest & 1) {