diff --git a/libpsx/src/libc.c b/libpsx/src/libc.c
index 2cf4064..607d8b0 100644
--- a/libpsx/src/libc.c
+++ b/libpsx/src/libc.c
@@ -286,6 +286,7 @@ static size_t cdromread(void *restrict ptr, size_t sz,
 			const size_t firstsz = SECTOR_SZ - first_sector_sz;
 
 			memcpy(ptr, &f->buf[first_sector_sz], firstsz);
+			ptr = (char *)ptr + firstsz;
 			f->pos += firstsz;
 			lseek(f->fildes, f->pos, SEEK_SET);
 			f->cache_available = 0;