fix: guard execve against null executor, inline-hook fork for dlopen (#42)#43
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…42) When libvproc.so is loaded via dlopen (not LD_PRELOAD), fork is not intercepted — ART's ProcessBuilder fork bypasses vproc, leaving REAL_FORK_CHILD unset. The fork child's execve enters virtual_execve and dereferences a null executor (TLS reset by bionic's pthread_atfork), crashing the second ProcessBuilder.start() call. - Add executor null check to execve early-return guard (preload.rs) - Add null guards to all executor functions that dereference the pointer - Add hook_libc_fork() to inline-hook fork like execve is hooked, ensuring REAL_FORK_CHILD is set even in dlopen scenario Bahtya
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Summary
ProcessBuilder.start()fails with error=795275776 when libvproc.so is loaded via dlopenget_current_executor()hook_libc_fork()to inline-hook fork (matching existinghook_libc_execve()pattern), ensuringREAL_FORK_CHILDis set even in dlopen scenarioRoot Cause
When loaded via dlopen, only execve is inline-hooked, not fork. ART's fork bypasses vproc, so
REAL_FORK_CHILDis never set in the child. The child's execve entersvirtual_execve, dereferences a null executor (TLS reset by bionic's pthread_atfork), and crashes.Test plan
Bahtya