1516558 - Memory leak in WriteExtraForMinidump due to fdopen without fclose

Status: RESOLVED FIXED

(Toolkit :: Crash Reporting, enhancement)

Description

[Jed Davis [:jld] ⟨⏰|UTC-7⟩ ⟦he/him⟧]

WriteExtraForMinidump uses fdopen() to create a FILE* that references the same underlying object as a given PRFileDesc*; it closes the PRFileDesc but not the FILE.

As pointed out in bug 1438106, this is intentional, because both the PRFileDesc and FILE will close the fd/handle, so closing both would be a double-close error.

However, leaking the FILE* would mean we're leaking all of its heap allocations.  (I haven't confirmed this with leak-checking tools, but I can't see how it could fail to be a leak.)


One way to fix this is to duplicate the file descriptor; Windows seems to have _dup for fds, and we also have a cross-platform abstraction of a duplicatable fd/handle in mozilla::ipc::FileDescriptor (and conversions to/from FILE* in FileDescriptorUtils.h).

The other way is to change ReadAndValidateExceptionTimeAnnotations to use NSPR I/O, and I don't know if NSPR has anything like fgets for “read a line”.

Comment 1

[Gabriele Svelto [:gsvelto] (PTO)]

This was fixed in bug 1547698 by switching everything to NSPR I/O.