3 Commits

Author SHA1 Message Date
Mark Mentovai
984749479f Introduce FromPointerCast<>(), with defined sign/zero-extension behavior
Some of the new Linux/Android tests were failing in 32-bit code where
pointers were being casted via reinterpret_cast<>() to LinuxVMAddress,
an unsigned 64-bit type. The behavior of such casts is
implementation-defined, and in this case, sign-extension was being used
to convert the 32-bit pointers to 64 bits, resulting in very large
(unsigned) LinuxVMAddress values that could not possibly refer to proper
addresses in a 32-bit process’ address space.

The offending reinterpret_cast<>() conversions have been replaced with
the new FromPointerCast<>(), which is careful to do sign-extension when
converting to a signed type, and zero-extension when converting to an
unsigned type like LinuxVMAddress.

Bug: crashpad:30
Test: crashpad_util_test FromPointerCast*:MemoryMap.*:ProcessMemory.*
Change-Id: I6f1408dc63369a8740ecd6015d657e4407a7c271
Reviewed-on: https://chromium-review.googlesource.com/488264
Reviewed-by: Joshua Peraza <jperaza@chromium.org>
2017-04-27 19:42:25 +00:00
Mark Mentovai
aa2bc55777 posix: Allow ScopedMmap::ResetAddrLen() to deal with overlap
It should be possible to shrink a region already supervised by
ScopedMmap, or in rare cases when ScopedMmap is supervising only a
smaller portion of an overall larger region, increase the size of the
region it supervises. This is now equivalent to the operation of
base::mac::ScopedMachVM::reset().

The Reset() and ResetAddrLen() methods are upgraded from a void return
to a bool return to indicate their success.

Bug: crashpad:30
Test: crashpad_util_test ScopedMmap*.ResetAddrLen_*
Change-Id: I564e154cd2387e8df3f83b416ecc1c83c9bcf71d
Reviewed-on: https://chromium-review.googlesource.com/464286
Commit-Queue: Mark Mentovai <mark@chromium.org>
Reviewed-by: Joshua Peraza <jperaza@chromium.org>
2017-03-31 02:54:23 +00:00
Mark Mentovai
96dc950eaf posix: Add ScopedMmap for managing memory-mapped regions
This wraps mmap(), munmap(), and mprotect().

Bug: crashpad:30
Test: crashpad_util_test ScopedMmap.*
Change-Id: If14363dfd00e314482cc91e53c7f4e3df737b0d3
Reviewed-on: https://chromium-review.googlesource.com/461361
Reviewed-by: Joshua Peraza <jperaza@chromium.org>
2017-03-28 18:30:14 +00:00