From d0c2d66fcc8db748edfe60e3b443eaff931f50e9 Mon Sep 17 00:00:00 2001 From: Azeem Shaikh Date: Wed, 17 May 2023 14:53:23 +0000 Subject: [PATCH] ftrace: Replace all non-returning strlcpy with strscpy strlcpy() reads the entire source buffer first. This read may exceed the destination size limit. This is both inefficient and can lead to linear read overflows if a source string is not NUL-terminated [1]. In an effort to remove strlcpy() completely [2], replace strlcpy() here with strscpy(). No return values were used, so direct replacement is safe. [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy [2] https://github.com/KSPP/linux/issues/89 Signed-off-by: Azeem Shaikh Reviewed-by: Kees Cook Acked-by: Masami Hiramatsu (Google) Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20230517145323.1522010-1-azeemshaikh38@gmail.com --- kernel/trace/ftrace.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 7646684..6a77edb 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -5743,7 +5743,7 @@ bool ftrace_filter_param __initdata; static int __init set_ftrace_notrace(char *str) { ftrace_filter_param = true; - strlcpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); + strscpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); return 1; } __setup("ftrace_notrace=", set_ftrace_notrace); @@ -5751,7 +5751,7 @@ __setup("ftrace_notrace=", set_ftrace_notrace); static int __init set_ftrace_filter(char *str) { ftrace_filter_param = true; - strlcpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); + strscpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); return 1; } __setup("ftrace_filter=", set_ftrace_filter); @@ -5763,14 +5763,14 @@ static int ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer); static int __init set_graph_function(char *str) { - strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); + strscpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); return 1; } __setup("ftrace_graph_filter=", set_graph_function); static int __init set_graph_notrace_function(char *str) { - strlcpy(ftrace_graph_notrace_buf, str, FTRACE_FILTER_SIZE); + strscpy(ftrace_graph_notrace_buf, str, FTRACE_FILTER_SIZE); return 1; } __setup("ftrace_graph_notrace=", set_graph_notrace_function); @@ -6569,8 +6569,8 @@ static int ftrace_get_trampoline_kallsym(unsigned int symnum, continue; *value = op->trampoline; *type = 't'; - strlcpy(name, FTRACE_TRAMPOLINE_SYM, KSYM_NAME_LEN); - strlcpy(module_name, FTRACE_TRAMPOLINE_MOD, MODULE_NAME_LEN); + strscpy(name, FTRACE_TRAMPOLINE_SYM, KSYM_NAME_LEN); + strscpy(module_name, FTRACE_TRAMPOLINE_MOD, MODULE_NAME_LEN); *exported = 0; return 0; } @@ -6933,7 +6933,7 @@ ftrace_func_address_lookup(struct ftrace_mod_map *mod_map, if (off) *off = addr - found_func->ip; if (sym) - strlcpy(sym, found_func->name, KSYM_NAME_LEN); + strscpy(sym, found_func->name, KSYM_NAME_LEN); return found_func->name; } @@ -6987,8 +6987,8 @@ int ftrace_mod_get_kallsym(unsigned int symnum, unsigned long *value, *value = mod_func->ip; *type = 'T'; - strlcpy(name, mod_func->name, KSYM_NAME_LEN); - strlcpy(module_name, mod_map->mod->name, MODULE_NAME_LEN); + strscpy(name, mod_func->name, KSYM_NAME_LEN); + strscpy(module_name, mod_map->mod->name, MODULE_NAME_LEN); *exported = 1; preempt_enable(); return 0; -- 2.7.4