Hi!
Any prelinked shared library is impossible to run on ppc64 without this
patch, as they immediately segfault. Say:
/bin/echo
works even if /lib64/ld64.so.1 is prelinked while
/lib64/ld64.so.1 /bin/echo
segfaults.
The problem is that ELF_PLAT_INIT is passed the virtual address of the
shared library, not the difference between the virtual address of the shared
library and p_vaddr of the first PT_LOAD segment in that library
(while for the interpreter interp_load_address is the bias).
ELF_PLAT_INIT sets gpr[2] to this absolute address, but
arch/ppc64/kernel/process.c (start_thread) assumes it is a bias and adds it
to entry and toc values loaded from the entry point descriptor.
For non-prelinked shared libraries, first PT_LOAD segment's p_vaddr is
typically 0 and thus load_addr == load_bias (which is why this bug has not
been discovered that long).
--- linux-2.5.72/fs/binfmt_elf.c.jj 2003-06-17 06:20:00.000000000 +0200
+++ linux-2.5.72/fs/binfmt_elf.c 2003-06-18 15:47:52.000000000 +0200
@@ -697,7 +697,7 @@ static int load_elf_binary(struct linux_
load_bias += error -
ELF_PAGESTART(load_bias + vaddr);
load_addr += load_bias;
- reloc_func_desc = load_addr;
+ reloc_func_desc = load_bias;
}
}
k = elf_ppnt->p_vaddr;
Jakub
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This archive was generated by hypermail 2b29 : Mon Jun 23 2003 - 22:00:24 EST