lib/oe/qa: ELFFile: check that a path is a file before opening it

When opening an ELF file check that a filename points to a normal file before
attempting to open it, as if the file turns out to be something more exotic like
a FIFO it could hang forever.

(From OE-Core rev: 4b3576bc30d8f8cdcde25189def8b059fc92b27c)

(From OE-Core rev: d3af2058e2753516b9aaf7f6d71162363eea11d4)

Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oe/qa.py

@@ -31,6 +31,9 @@ class ELFFile:
         self.objdump_output = {}
 
     def open(self):
+        if not os.path.isfile(self.name):
+            raise Exception("File is not a normal file")
+
         self.file = file(self.name, "r")
         self.data = self.file.read(ELFFile.EI_NIDENT+4)