diff --git a/a.out b/a.out
index 829193d..7910224 100755
Binary files a/a.out and b/a.out differ
diff --git a/helpelf b/helpelf
index 3dec206..c64aa80 100755
Binary files a/helpelf and b/helpelf differ
diff --git a/main.c b/main.c
index fa9f6d3..e1b78a2 100644
--- a/main.c
+++ b/main.c
@@ -172,7 +172,11 @@ int parse_elf_header64(struct Elf64_Ehdr* header, FILE* fp)
 int read_elf_magic(FILE* fp)
 {
 	char buf[5] = {0};
-	fread(buf, 1, 4, fp);
+	if (!fread(buf, 1, 4, fp))
+	{
+		puts("Read error.");
+		exit(-EIO);
+	}
 	if (memcmp(buf, "\177ELF", 4) == 0) return 1;
 	return 0;
 }
@@ -206,7 +210,16 @@ void check_dynamic32(struct Elf32_Ehdr* header, FILE* fp)
 	// read program headers	
 	fseek(fp, header->e_phoff, SEEK_SET);
 	struct Elf32_Phdr *p_headers = malloc(header->e_phnum * sizeof(struct Elf32_Phdr));
-	fread(p_headers, sizeof(struct Elf32_Phdr), header->e_phnum, fp);
+	if (!p_headers)
+	{
+		puts("Memory allocation error.");
+		exit(-ENOMEM);
+	}
+	if (!fread(p_headers, sizeof(struct Elf32_Phdr), header->e_phnum, fp))
+	{
+		puts("Read error.");
+		exit(-EIO);
+	}
 
 	const char* interpstr = NULL;
 
@@ -218,8 +231,17 @@ void check_dynamic32(struct Elf32_Ehdr* header, FILE* fp)
 
 			// Get interpreter path
 			interpstr = malloc(p_headers[i].p_filesz);
+			if (!interpstr)
+			{
+				puts("Memory allocation error.");
+				exit(-ENOMEM);
+			}
 			fseek(fp, p_headers[i].p_offset, SEEK_SET);
-			fread((char*)interpstr, 1, p_headers[i].p_filesz, fp);
+			if (!fread((char*)interpstr, 1, p_headers[i].p_filesz, fp))
+			{
+				puts("Read error.");
+				exit(-EIO);
+			}
 			break;
 		}
 	}
@@ -305,15 +327,10 @@ void display_elf32(struct Elf32_Ehdr* header, FILE* fp)
 	
 	if (verbose)
 	{
-		check_dynamic32(header, fp);	
+		check_dynamic32(header, fp);
 	}
 }
 
-void check_nx32(struct Elf32_Ehdr* header, FILE* fp)
-{
-
-}
-
 void check_sec32(struct Elf32_Ehdr* header, FILE* fp)
 {
 	/* NX:
@@ -324,7 +341,11 @@ void check_sec32(struct Elf32_Ehdr* header, FILE* fp)
 	for (size_t i=0; i<header->e_phnum; i++)
 	{
 		struct Elf32_Phdr p_header;
-		fread (&p_header, 1, sizeof(struct Elf32_Phdr), fp);
+		if (!fread(&p_header, 1, sizeof(struct Elf32_Phdr), fp))
+		{
+			puts("Read error.");
+			exit(-EIO);
+		}
 		if (p_header.p_type == PT_GNU_STACK)
 		{
 			if (p_header.p_flags & PF_X)
@@ -347,13 +368,31 @@ void check_sec32(struct Elf32_Ehdr* header, FILE* fp)
 
 	// Read section headers
 	struct Elf32_Shdr *s_headers = malloc(header->e_shnum * sizeof(struct Elf32_Shdr));
-	fread(s_headers, sizeof(struct Elf32_Shdr), header->e_shnum, fp);
+	if (!s_headers)
+	{
+		puts("Memory allocation error.");
+		exit(-ENOMEM);
+	}
+	if (!fread(s_headers, sizeof(struct Elf32_Shdr), header->e_shnum, fp))
+	{
+		puts("Read error.");
+		exit(-EIO);
+	}
 
 	// Find section name string table (at e_shstrndx) and read it
 	struct Elf32_Shdr s_header_str = s_headers[header->e_shstrndx];
 	char* s_header_strtab = malloc(s_header_str.sh_size);
+	if (!s_header_strtab)
+	{
+		puts("Memory allocation error.");
+		exit(-ENOMEM);
+	}
 	fseek(fp, s_header_str.sh_offset, SEEK_SET);
-	fread(s_header_strtab, 1, s_header_str.sh_size, fp);
+	if (!fread(s_header_strtab, 1, s_header_str.sh_size, fp))
+	{
+		puts("Read error.");
+		exit(-EIO);
+	}
 
 	for (size_t i=0; i<header->e_shnum; i++)
 	{
@@ -365,14 +404,32 @@ void check_sec32(struct Elf32_Ehdr* header, FILE* fp)
 			// load symbol table
 			unsigned int nsyms = s_headers[i].sh_size / s_headers[i].sh_entsize;
 			struct Elf32_Sym *syms = malloc(s_headers[i].sh_size);
+			if (!syms)
+			{
+				puts("Memory allocation error.");
+				exit(-EIO);
+			}
 			fseek(fp, s_headers[i].sh_offset, SEEK_SET);
-			fread(syms, s_headers[i].sh_size, 1, fp);
+			if (!fread(syms, s_headers[i].sh_size, 1, fp))
+			{
+				puts("Read error.");
+				exit(-EIO);
+			}
 
 			// load string table
 			struct Elf32_Shdr str_header = s_headers[s_headers[i].sh_link];
 			char* strtab = malloc(str_header.sh_size);
+			if (!strtab)
+			{
+				puts("Memory allocation error.");
+				exit(-ENOMEM);
+			}
 			fseek(fp, str_header.sh_offset, SEEK_SET);
-			fread(strtab, 1, str_header.sh_size, fp);
+			if (!fread(strtab, 1, str_header.sh_size, fp))
+			{
+				puts("Read error.");
+				exit(-EIO);
+			}
 
 			// iterate through symbols, check for __stack_chk_fail
 			for (size_t j=0; j<nsyms; j++)
@@ -393,7 +450,16 @@ void check_sec32(struct Elf32_Ehdr* header, FILE* fp)
 	// Read program headers
 	fseek(fp, header->e_phoff, SEEK_SET);
 	struct Elf32_Phdr *p_headers = malloc(header->e_phnum * sizeof(struct Elf32_Phdr));
-	fread (p_headers, sizeof(struct Elf32_Phdr), header->e_phnum, fp);
+	if (!p_headers)
+	{
+		puts("Memory allocation error.");
+		exit(-ENOMEM);
+	}
+	if (!fread (p_headers, sizeof(struct Elf32_Phdr), header->e_phnum, fp))
+	{
+		puts("Read error.");
+		exit(-EIO);
+	}
 
 	Elf32_Off dyn_off = 0;
 	Elf32_Word dyn_size = 0;
@@ -415,8 +481,17 @@ void check_sec32(struct Elf32_Ehdr* header, FILE* fp)
 	{
 		int n = dyn_size / sizeof(struct Elf32_Dyn);
 		struct Elf32_Dyn *dyns = malloc(dyn_size);
+		if (!dyns)
+		{
+			puts("Memory allocation error.");
+			exit(-ENOMEM);
+		}
 		fseek(fp, dyn_off, SEEK_SET);
-		fread(dyns, sizeof(struct Elf32_Dyn), n, fp);
+		if (!fread(dyns, sizeof(struct Elf32_Dyn), n, fp))
+		{
+			puts("Read error.");
+			exit(-EIO);
+		}
 
 		for (int i=0; i<n; i++)
 		{
@@ -441,7 +516,11 @@ unsigned char read_elf_obj_size(FILE* fp)
 {
 	unsigned char local_elf_obj_size = 0;
 	fseek(fp, 4, SEEK_SET);
-	fread(&local_elf_obj_size, 1, 1, fp);
+	if (!fread(&local_elf_obj_size, 1, 1, fp))
+	{
+		puts("Failed to read ELF object size");
+		exit(-EIO);
+	}
 	rewind(fp);
 	return local_elf_obj_size;
 }
@@ -472,7 +551,7 @@ int main(int argc, char* argv[])
 	char* filename = argv[1];
 	if (!filename)
 	{
-		printf("Error parsing filename.\n");
+		puts("Error parsing filename.");
 		return -EINVAL;
 	}
 	
@@ -486,7 +565,7 @@ int main(int argc, char* argv[])
 	int is_elf = read_elf_magic(elf_file);
 	if (!is_elf)
 	{
-		printf("Not a valid ELF file.\n");
+		puts("Not a valid ELF file.");
 		return -EINVAL;
 	}
 
@@ -501,7 +580,7 @@ int main(int argc, char* argv[])
 			struct Elf32_Ehdr elf32_header = {0};
 			if (parse_elf_header32(&elf32_header, elf_file))
 			{
-				printf("Failed to parse 32-bit ELF header\n");
+				puts("Failed to parse 32-bit ELF header");
 				return -EINVAL;
 			}
 			display_elf32(&elf32_header, elf_file);
@@ -511,13 +590,13 @@ int main(int argc, char* argv[])
 			struct Elf64_Ehdr elf64_header = {0};
 			if (parse_elf_header64(&elf64_header, elf_file))
 			{
-				printf("Failed to parse 64-bit ELF header\n");
+				puts("Failed to parse 64-bit ELF header");
 				return -EINVAL;
 			}
 			display_elf64(&elf64_header);
 			break;
 		default:
-			printf("Invalid ELF object size\n");
+			puts("Invalid ELF object size");
 			return -EINVAL;
 	}