The following commit has been merged into the core/kprobes branch of tip: Commit-ID: 66e9b0717102507e64f638790eaece88765cc9e5 Gitweb: https://git.kernel.org/tip/66e9b0717102507e64f638790eaece88765cc9e5 Author: Thomas Gleixner <t...@linutronix.de> AuthorDate: Tue, 10 Mar 2020 14:04:34 +01:00 Committer: Thomas Gleixner <t...@linutronix.de> CommitterDate: Tue, 19 May 2020 15:56:20 +02:00
kprobes: Prevent probes in .noinstr.text section Instrumentation is forbidden in the .noinstr.text section. Make kprobes respect this. Signed-off-by: Thomas Gleixner <t...@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.char...@oracle.com> Acked-by: Peter Zijlstra <pet...@infradead.org> Acked-by: Masami Hiramatsu <mhira...@kernel.org> Link: https://lkml.kernel.org/r/20200505134100.179862...@linutronix.de --- include/linux/module.h | 2 ++ kernel/kprobes.c | 18 ++++++++++++++++++ kernel/module.c | 3 +++ 3 files changed, 23 insertions(+) diff --git a/include/linux/module.h b/include/linux/module.h index 1192097..d849d06 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -458,6 +458,8 @@ struct module { void __percpu *percpu; unsigned int percpu_size; #endif + void *noinstr_text_start; + unsigned int noinstr_text_size; #ifdef CONFIG_TRACEPOINTS unsigned int num_tracepoints; diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 9eb5acf..3f310df 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -2229,6 +2229,12 @@ static int __init populate_kprobe_blacklist(unsigned long *start, /* Symbols in __kprobes_text are blacklisted */ ret = kprobe_add_area_blacklist((unsigned long)__kprobes_text_start, (unsigned long)__kprobes_text_end); + if (ret) + return ret; + + /* Symbols in noinstr section are blacklisted */ + ret = kprobe_add_area_blacklist((unsigned long)__noinstr_text_start, + (unsigned long)__noinstr_text_end); return ret ? : arch_populate_kprobe_blacklist(); } @@ -2248,6 +2254,12 @@ static void add_module_kprobe_blacklist(struct module *mod) end = start + mod->kprobes_text_size; kprobe_add_area_blacklist(start, end); } + + start = (unsigned long)mod->noinstr_text_start; + if (start) { + end = start + mod->noinstr_text_size; + kprobe_add_area_blacklist(start, end); + } } static void remove_module_kprobe_blacklist(struct module *mod) @@ -2265,6 +2277,12 @@ static void remove_module_kprobe_blacklist(struct module *mod) end = start + mod->kprobes_text_size; kprobe_remove_area_blacklist(start, end); } + + start = (unsigned long)mod->noinstr_text_start; + if (start) { + end = start + mod->noinstr_text_size; + kprobe_remove_area_blacklist(start, end); + } } /* Module notifier call back, checking kprobes on the module */ diff --git a/kernel/module.c b/kernel/module.c index faf7337..72ed2b3 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3150,6 +3150,9 @@ static int find_module_sections(struct module *mod, struct load_info *info) } #endif + mod->noinstr_text_start = section_objs(info, ".noinstr.text", 1, + &mod->noinstr_text_size); + #ifdef CONFIG_TRACEPOINTS mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs", sizeof(*mod->tracepoints_ptrs),
