Messages in this thread Patch in this message | | | From | Zhou Chengming <> | Subject | [PATCH] livepatch: x86: bugfix about kASLR | Date | Wed, 4 Nov 2015 17:32:12 +0800 |
| |
When enable KASLR, func->old_addr will be set to zero and livepatch will find the right old address. But for reloc, livepatch just verify it using reloc->val (old addr from user), so verify failed and report "kernel mismatch" error.
Reported-by: Cyril B. <cbay@alwaysdata.com> Signed-off-by: Zhou Chengming <zhouchengming1@huawei.com> --- kernel/livepatch/core.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-)
diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index 53196e2..c8885c6 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -311,7 +311,12 @@ static int klp_write_object_relocations(struct module *pmod, return -EINVAL; for (reloc = obj->relocs; reloc->name; reloc++) { - if (!klp_is_module(obj)) { + +#if defined(CONFIG_RANDOMIZE_BASE) + /* KASLR is enabled, disregard old_addr from user */ + reloc->val = 0; +#endif + if (reloc->val && !klp_is_module(obj)) { ret = klp_verify_vmlinux_symbol(reloc->name, reloc->val); if (ret) -- 1.7.7
| |