The broker attempts to use sbrk() to allocate memory to track ptrace
attachments. If the process failed due to an OOM, this system call might
fail, the broker falls back to saving attachments on the stack, and then
overruns the stack.
This change updates the broker to use sys_mmap() instead of sbrk(),
which is expected to work at least as well. If sys_mmap() fails or
the first mapped page is exhausted, further attachments fail without
attempting to save them to the stack.
Bug: chromium:1128441
Change-Id: Ibffaa986403adaf3178ee77e6d210053fbf60f26
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/2488280
Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Joshua Peraza <jperaza@chromium.org>
This patch adds the class ExceptionHandlerProtocol to contain all the
relevant types, but should not make any functional changes.
Change-Id: I65ada239a6bf3195899fdd96f005c042cdd59749
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/1575796
Commit-Queue: Joshua Peraza <jperaza@chromium.org>
Reviewed-by: Mark Mentovai <mark@chromium.org>
This change:
1. Updates the broker's memory reading protocol to enable short reads.
2. Updates Ptracer to allow short reads.
3. Updates the broker to allow reading from a memory file.
4. Updates the broker's default file root to be "/proc/[pid]/".
5. Adds PtraceConnection::Memory() to produce a suitable memory reader
for a connection type.
Bug: crashpad:30
Change-Id: I8c004016065d981acd1fa74ad1b8e51ce07c7c85
Reviewed-on: https://chromium-review.googlesource.com/991455
Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Joshua Peraza <jperaza@chromium.org>
Some files, such as /proc/[pid]/maps, may not be accessible to the
handler. This enables the handler access to the contents of those files
via the broker.
This change reads maps and auxv using ReadFileContents.
Bug: crashpad:30
Change-Id: Ia19b498bae473c616ea794ab51c3f22afd5795be
Reviewed-on: https://chromium-review.googlesource.com/989406
Reviewed-by: Mark Mentovai <mark@chromium.org>
A PtraceBroker/Client pair implement a PtraceConnection over a socket.
The broker runs in a process with `ptrace` capabilities for the target
process and serves requests for the client over a socket.
Bug: crashpad:30
Change-Id: Ied19bcedf84b46c8f68440fd1c284b2126470e5e
Reviewed-on: https://chromium-review.googlesource.com/780397
Commit-Queue: Joshua Peraza <jperaza@chromium.org>
Reviewed-by: Mark Mentovai <mark@chromium.org>
