dependency, then the dso never has its DAG initialized. Empty DAG makes ref_dag() call in dlopen() a nop, and the dso refcount is off by one. Initialize the DAG on the first dlopen() call, using a boolean flag to prevent double initialization. From the PR (edited): Assume we have a library liba.so, containing a function a(), and a library libb.so, containing function b(). liba.so needs functionality from libb.so, so liba.so links in libb.so. An application doesn't know about the relation between these libraries, but needs to call a() and b(). It dlopen()s liba.so and obtains a pointer to a(), then it dlopen()s libb.so and obtains a pointer to b(). As soon as the application doesn't need a() anymore, it dlclose()s liba.so. Expected result: the pointer to b() is still valid and can be called Actual result: the pointer to b() has become invalid, even though the application did not dlclose() the handle to libb.so. On calling b(), the application crashes with a segmentation fault. PR: misc/151861 Based on patch by: jh Reviewed by: kan Tested by: Arjan van Leeuwen <freebsd-maintainer opera com> MFC after: 1 week |
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.. | ||
amd64 | ||
arm | ||
i386 | ||
ia64 | ||
mips | ||
powerpc | ||
powerpc64 | ||
sparc64 | ||
debug.c | ||
debug.h | ||
libmap.c | ||
libmap.h | ||
Makefile | ||
malloc.c | ||
map_object.c | ||
rtld_lock.c | ||
rtld_lock.h | ||
rtld_tls.h | ||
rtld.1 | ||
rtld.c | ||
rtld.h | ||
Symbol.map | ||
xmalloc.c |