From f5aebe74113f488cad5444ab66f28c08d9c0a39a Mon Sep 17 00:00:00 2001 From: "chenzefeng (A)" Date: Wed, 20 Feb 2019 12:37:54 +0000 Subject: x86: livepatch: Treat R_X86_64_PLT32 as R_X86_64_PC32 Signed-off-by: chenzefeng On x86-64, for 32-bit PC-relacive branches, we can generate PLT32 relocation, instead of PC32 relocation. and R_X86_64_PLT32 can be treated the same as R_X86_64_PC32 since linux kernel doesn't use PLT. commit b21ebf2fb4cd ("x86: Treat R_X86_64_PLT32 as R_X86_64_PC32") been fixed for the module loading, but not fixed for livepatch relocation, which will fail to load livepatch with the error message as follow: relocation failed for symbol at This issue only effacted the kernel version from 4.0 to 4.6, becauce the function klp_write_module_reloc is introduced by: commit b700e7f03df5 ("livepatch: kernel: add support for live patching") and deleted by: commit 425595a7fc20 ("livepatch: reuse module loader code to write relocations") Signed-off-by: chenzefeng Reviewed-by: Petr Mladek Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/livepatch.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86/kernel/livepatch.c') diff --git a/arch/x86/kernel/livepatch.c b/arch/x86/kernel/livepatch.c index d1d35ccffed3..579f8f813ce0 100644 --- a/arch/x86/kernel/livepatch.c +++ b/arch/x86/kernel/livepatch.c @@ -58,6 +58,7 @@ int klp_write_module_reloc(struct module *mod, unsigned long type, val = (s32)value; break; case R_X86_64_PC32: + case R_X86_64_PLT32: val = (u32)(value - loc); break; default: -- cgit v1.2.3