Merge pull request libarchive#2668 from stoeckmann/7z_oob

7zip: Fix out of boundary access

Author: mmatuska

libarchive/archive_read_support_format_7zip.c

@@ -80,7 +80,7 @@
 /*
  * ELF format
  */
-#define ELF_HDR_MIN_LEN 0x34
+#define ELF_HDR_MIN_LEN 0x3f
 #define ELF_HDR_EI_CLASS_OFFSET 0x04
 #define ELF_HDR_EI_DATA_OFFSET 0x05
 
@@ -811,6 +811,8 @@ find_elf_data_sec(struct archive_read *a)
 			strtab_size = (*dec32)(
 			    h + e_shstrndx * e_shentsize + 0x14);
 		}
+		if (strtab_size < 6 || strtab_size > SIZE_MAX)
+			break;
 
 		/*
 		 * Read the STRTAB section to find the .data offset