drmodtrack fails to handle non-contiguous ELF libraries #2213
Assignees
Comments
derekbruening
added a commit
that referenced
this issue
Feb 23, 2017
Adds handling of gaps inside ELF libraries to drmodtrack. Additional entries are added both to the online vector and the written file. The containing_index field added previously is used to point to the main entry from sub-entries. It's not easy to write a test without making a linker script, but on many recent Linux distros there are gaps in some or even all system libraries, including some of my machines, so we'll get at least some future regression coverage. Fixes #2213
derekbruening
added a commit
that referenced
this issue
Feb 23, 2017
Adds handling of gaps inside ELF libraries to drmodtrack. Additional entries are added both to the online vector and the written file. The containing_index field added previously is used to point to the main entry from sub-entries. It's not easy to write a test without making a linker script, but on many recent Linux distros there are gaps in some or even all system libraries, including some of my machines, so we'll get at least some future regression coverage. Fixes #2213
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
The drmodtrack extension, evolved from drcov's library tracker, completely ignores gaps and the possibility of non-contiguous ELF mappings. Now that drmodtrack is used for drcachesim this is being used in more places and the gap issue is now a blocker. For drcachesim, one app has its ld.so with a big gap containing other libs inside it, and drmodtrack ends up thinking that every lib in between is actually in ld.so. This leads to crashes in drraw2trace post-processing.
The text was updated successfully, but these errors were encountered: