From: Li Huafei <lihuafei1@huawei.com> hulk inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I5CJ7X -------------------------------- For exception frames, we need to check NIP in addition to PC. When a task is interrupted, NIP is the interrupt return address. The function where the NIP is located is also on the stack. Fixes: ec2244b5adcf ("livepatch/ppc64: only check stack top") Fixes: 2a7c3db6e6a8 ("livepatch/powerpc64: Add arch_klp_module_check_calltrace") Signed-off-by: Li Huafei <lihuafei1@huawei.com> Reviewed-by: Xu Kuohai <xukuohai@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- arch/powerpc/kernel/livepatch_64.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-) diff --git a/arch/powerpc/kernel/livepatch_64.c b/arch/powerpc/kernel/livepatch_64.c index 2487fab569a7..acd3658d37a3 100644 --- a/arch/powerpc/kernel/livepatch_64.c +++ b/arch/powerpc/kernel/livepatch_64.c @@ -326,9 +326,14 @@ static int klp_check_jump_func(struct stackframe *frame, void *data) struct walk_stackframe_args *args = data; struct klp_func_list *check_funcs = args->check_funcs; - if (!check_func_list(check_funcs, &args->ret, frame->pc)) { + /* check the PC first */ + if (!check_func_list(check_funcs, &args->ret, frame->pc)) return args->ret; - } + + /* check NIP when the exception stack switching */ + if (frame->nip && !check_func_list(check_funcs, &args->ret, frame->nip)) + return args->ret; + return 0; } @@ -430,11 +435,19 @@ static int check_module_calltrace(struct stackframe *frame, void *data) { struct walk_stackframe_args *args = data; - if (within_module_core(frame->pc, args->mod)) { - pr_err("module %s is in use!\n", args->mod->name); - return (args->ret = -EBUSY); - } + /* check the PC first */ + if (within_module_core(frame->pc, args->mod)) + goto err_out; + + /* check NIP when the exception stack switching */ + if (frame->nip && within_module_core(frame->nip, args->mod)) + goto err_out; + return 0; + +err_out: + pr_err("module %s is in use!\n", args->mod->name); + return (args->ret = -EBUSY); } int arch_klp_module_check_calltrace(void *data) -- 2.20.1