[lldb/plugin] Fix heap-use-after-free in ScriptedProcess::ReadMemory #3676
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This patch introduces a new method to SBData: SetDataWithOwnership. Instead of referencing the pointer to the data, this method copies the data buffer into lldb's heap memory. This can prevent having the underlying DataExtractor object point to freed/garbage-collected memory. Differential Revision: https://reviews.llvm.org/D115652 Signed-off-by: Med Ismail Bennani <[email protected]>
This commit should fix a heap-use-after-free bug that was caught by the sanitizer bot. The issue is that we were reading memory from a second target into a `SBData` object in Python, that was passed to lldb's internal `ScriptedProcess::DoReadMemory` C++ method. The ScriptedPythonInterface then extracts the underlying `DataExtractor` from the `SBData` object, and is used to read the memory with the appropriate address size and byte order. Unfortunately, it seems that even though the DataExtractor object was still valid, it pointed to invalid, possibly garbage-collected memory from Python. To mitigate this, the patch uses `SBData::SetDataWithOwnership` to copy the pointed buffer to lldb's heap memory which prevents the use-after-free error. rdar://84511405 Differential Revision: https://reviews.llvm.org/D115654 Signed-off-by: Med Ismail Bennani <[email protected]>
Signed-off-by: Med Ismail Bennani <[email protected]>
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This commit should fix a heap-use-after-free bug that was caught by the
sanitizer bot.
The issue is that we were reading memory from a second target into a
SBDataobject in Python, that was passed to lldb's internalScriptedProcess::DoReadMemoryC++ method.The ScriptedPythonInterface then extracts the underlying
DataExtractorfrom the
SBDataobject, and is used to read the memory with theappropriate address size and byte order.
Unfortunately, it seems that even though the DataExtractor object was
still valid, it pointed to invalid, possibly garbage-collected memory
from Python.
To mitigate this, the patch uses
SBData::SetDataWithOwnershipto copythe pointed buffer to lldb's heap memory which prevents the
use-after-free error.
rdar://84511405
Differential Revision: https://reviews.llvm.org/D115654
Signed-off-by: Med Ismail Bennani [email protected]