Commit Graph

3 Commits

Author SHA1 Message Date
Pavel Labath 122c50d5ef Fix DWARFDataExtractor::getRelocatedValue near EOF
Summary:
If we have an (invalid) relocation which relocates bytes which partially
lie outside the range of the relocated section, the getRelocatedValue
would return confusing results. It would first read zero (because that's
what the underlying DataExtractor api does for out-of-bounds reads), and
then relocate that zero anyway.

A more appropriate behavior is to return zero straight away. This is
what this patch does.

Reviewers: dblaikie, jhenderson

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D78113
2020-04-15 12:47:57 +02:00
Pavel Labath 5754a61e57 [DataExtractor] Improve error message when we run off the end of the buffer
Summary: Include the offset at which this happened.

Reviewers: dblaikie, jhenderson

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75265
2020-02-28 09:02:33 +01:00
Pavel Labath 3c36d8dad5 Introduce DWARFDataExtractor::getInitialLength
Summary:
This patch introduces a function to house the code needed to do the
DWARF64 detection dance. The function decodes the initial length field
and returns it as a pair containing the actual length, and the DWARF
encoding.

This patch does _not_ attempt to handle the problem of detecting lengths
which extend past the size of the section, or cases when reads of a
single contribution accidentally escape beyond its specified length, but
I think it's useful in its own right.

Reviewers: dblaikie, jhenderson, ikudrin

Subscribers: hiraditya, probinson, aprantl, JDevlieghere, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74560
2020-02-26 17:07:58 +01:00