Fix vmmap coredump test #1391
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Fix vmmap coredump test #1391
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This commit fixes two issues and test them. 1. It changes the reads in `get_ehdr` to partial reads so that inability to read the `vmmap.start` address there will not crash Pwndbg with `gdb.error` but instead we will simply return `None` as expected from this function. This crash could happen on Debian 10 (GDB 8.2.1) and Ubuntu 18.04 (not sure which GDB) when you did: - gdb ./binary-that-crashes - `run` - `generate-core-file /tmp/core` - `file` - to unload the binary - `core-file /tmp/core` - to load the generated core At this point I think we may have preserved the old vmmap info and use it in `get_ehdr` maybe, which then crashed? I am not sure, but this fix here works. To test this behavior properly I also added the `unload_file` parametrization to the `test_command_vmmap_on_coredump_on_crash_simple_binary` test. 2. We fix the vmmap coredump test case when the `info proc mappings` returns nothing on core dumps on old GDBs. In such case we are missing the vmmap info about the binary mapping, so now we properly remove it in the test.
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This commits/PR fixes two issues and test them.
get_ehdrto partial reads so that inabilityto read the
vmmap.startaddress there will not crash Pwndbg withgdb.errorbut instead we will simply returnNoneas expected fromthis function. This crash could happen on Debian 10 (GDB 8.2.1) and
Ubuntu 18.04 (not sure which GDB) when you did:
rungenerate-core-file /tmp/corefile- to unload the binarycore-file /tmp/core- to load the generated coreAt this point I think we may have preserved the old vmmap info and use
it in
get_ehdrmaybe, which then crashed? I am not sure, but this fixhere works.
To test this behavior properly I also added the
unload_fileparametrization to the
test_command_vmmap_on_coredump_on_crash_simple_binarytest.info proc mappingsreturns nothing on coredumps on old GDBs. In such case we are missing the vmmap info about
the binary mapping, so now we properly remove it in the test.