tree e2c060cc4bf72aeb85e8ba285f0c03fc14adaa69
parent 3474270abdebbd6235c1391e54aaba5924276666
author David Benjamin <davidben@google.com> 1537652996 -0500
committer Adam Langley <agl@google.com> 1538415284 +0000

Fix undefined function pointer casts in IMPLEMENT_PEM_*.

While it is okay to cast function pointers into different types for
generic storage, the pointer must be cast back to the exact same type
when calling. In particular, although C libraries do this sort of thing
all the time, calling a T* d2i function as a void* d2i function is
undefined:

  If the function is defined with a type that is not compatible with the
  type (of the expression) pointed to by the expression that denotes the
  called function, the behavior is undefined

Fix some instances in the PEM/ASN1 wrapper functions. Synthesize helper
functions instead.

This CL just addresses the function pointer issues. The inherited legacy
OpenSSL ASN.1 code is still full other questionable data pointer dances
that will be much more difficult to excise. Continuing to exise that
code altogether (it is already unshipped from Cronet and unshipped from
Chrome but for WebRTC) is probably a better tack there.

This removes one (of many many) places where we require
-fsanitize-cfi-icall-generalize-pointers.

Bug: chromium:785442
Change-Id: Id8056ead6ef471f0fdf263bb50dc659da500e8ce
Reviewed-on: https://boringssl-review.googlesource.com/32105
Reviewed-by: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <alangley@gmail.com>