Messages in this thread | | | Subject | Re: [PATCH] modpost: abort if a module name is too long | From | Wanlong Gao <> | Date | Wed, 31 May 2017 10:23:50 +0800 |
| |
Hi Jessica,
On 2017/5/29 17:10, Jessica Yu wrote: > +++ Xie XiuQi [20/05/17 15:46 +0800]: >> From: Wanlong Gao <gaowanlong@huawei.com> >> >> Module name has a limited length, but currently the build system >> allows the build finishing even if the module name is too long. >> >> CC /root/kprobe_example/abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz.mod.o >> /root/kprobe_example/abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz.mod.c:9:2: >> warning: initializer-string for array of chars is too long [enabled by default] >> .name = KBUILD_MODNAME, >> ^ >> >> but it's merely a warning. >> >> This patch adds the check of the module name length in modpost and stops >> the build properly. >> >> Signed-off-by: Wanlong Gao <gaowanlong@huawei.com> >> Signed-off-by: Xie XiuQi <xiexiuqi@huawei.com> >> --- >> scripts/mod/modpost.c | 11 +++++++++++ >> 1 file changed, 11 insertions(+) >> >> diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c >> index 30d752a..db11c57 100644 >> --- a/scripts/mod/modpost.c >> +++ b/scripts/mod/modpost.c >> @@ -2166,6 +2166,17 @@ static int add_versions(struct buffer *b, struct module *mod) >> { >> struct symbol *s, *exp; >> int err = 0; >> + const char *mod_name; >> + >> + mod_name = strrchr(mod->name, '/'); >> + if (mod_name == NULL) >> + mod_name = mod->name; >> + else >> + mod_name++; >> + if (strlen(mod_name) >= MODULE_NAME_LEN) { >> + merror("module name is too long [%s.ko]\n", mod->name); >> + return 1; >> + } > > Hi Xie, > > This check shouldn't be in add_versions() (which does something else entirely), > it should probably be put in a separate helper function called from main. But > I'm not a big fan of the extra string manipulation to do something this simple. > > I think this check can be vastly simplified, how about something like the > following?
This looks better, would you apply your following patch?
Reviewed-by: Wanlong Gao <gaowanlong@huawei.com> Tested-by: Wanlong Gao <gaowanlong@huawei.com>
Thanks, Wanlong Gao
> > diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c > index 48397fe..bb09fc7 100644 > --- a/scripts/mod/modpost.c > +++ b/scripts/mod/modpost.c > @@ -2139,6 +2139,9 @@ static void add_header(struct buffer *b, struct module *mod) > "#endif\n"); > buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n"); > buf_printf(b, "};\n"); > + buf_printf(b, "\n"); > + buf_printf(b, "static void __attribute__((section(\".discard\"), used)) __modname_test(void)\n"); > + buf_printf(b, "{ BUILD_BUG_ON(sizeof(KBUILD_MODNAME) > MODULE_NAME_LEN); }\n"); > } > > static void add_intree_flag(struct buffer *b, int is_intree) > > This simply checks if KBUILD_MODNAME > MODULE_NAME_LEN and breaks the build if > it does. > > Jessica > >> for (s = mod->unres; s; s = s->next) { >> exp = find_symbol(s->name); >> -- >> 1.8.3.1 >> > > . >
| |