Don't leak compartment name pointers after dlclose() #2389
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bsdjhb
commented
Apr 3, 2025
bsdjhb
commented
- proc: Update c18n compartments sysctl handler for struct rtld_c18n_compart
- proc: Validate bounds of entire c18n comparts array once
- proc: Better handle short reads in proc_read_string_properly
jrtc27
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Apr 3, 2025
bsdjhb
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This no longer has any kernel changes, just fixes to rtld to avoid leaking pointers after dlclose(). This fixes chromium child processes for me, but note that rtld currently doesn't ever delete compartments, so compartments for dlclosed objects still remain and still list the unloaded objects as members. Fixing that requires larger changes to rtld_c18n and in particular avoiding pre-creating compartments for the internal policy. |
In particular, the names allocated for sub-object compartments can be freed after dlclose() leaving a dangling pointer in the comparts entry. While here, add a wrapper for strdup() so that the bytes used for the allocated names are accounted for.
Now that compart_id_allocate() allocates its own internal storage for compartment names, this allocated copy doesn't need to persist while an object file is loaded.
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I've dropped the last change for now so it can be a separate PR, this is now just the fixes to make the sysctl work after dlclose(). |
bsdjhb
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