From cb9b55d21fe06ca5e4ba244bb5aac0afeb745c8e Mon Sep 17 00:00:00 2001 From: Matthias Maennich Date: Fri, 6 Sep 2019 11:32:28 +0100 Subject: modpost: add support for symbol namespaces Add support for symbols that are exported into namespaces. For that, extract any namespace suffix from the symbol name. In addition, emit a warning whenever a module refers to an exported symbol without explicitly importing the namespace that it is defined in. This patch consistently adds the namespace suffix to symbol names exported into Module.symvers. Example warning emitted by modpost in case of the above violation: WARNING: module ums-usbat uses symbol usb_stor_resume from namespace USB_STORAGE, but does not import it. Co-developed-by: Martijn Coenen Signed-off-by: Martijn Coenen Reviewed-by: Joel Fernandes (Google) Reviewed-by: Greg Kroah-Hartman Signed-off-by: Matthias Maennich Signed-off-by: Jessica Yu --- scripts/mod/modpost.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'scripts/mod/modpost.h') diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index 8453d6ac2f77..9626bf3e7424 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -109,6 +109,11 @@ buf_printf(struct buffer *buf, const char *fmt, ...); void buf_write(struct buffer *buf, const char *s, int len); +struct namespace_list { + struct namespace_list *next; + char namespace[0]; +}; + struct module { struct module *next; const char *name; @@ -121,6 +126,8 @@ struct module { struct buffer dev_table_buf; char srcversion[25]; int is_dot_o; + // Actual imported namespaces + struct namespace_list *imported_namespaces; }; struct elf_info { -- cgit v1.2.3 From 1d082773ff30e97c8bc10b65c4aa0d073664caac Mon Sep 17 00:00:00 2001 From: Matthias Maennich Date: Fri, 6 Sep 2019 11:32:31 +0100 Subject: modpost: add support for generating namespace dependencies This patch adds an option to modpost to generate a .ns_deps file per module, containing the namespace dependencies for that module. E.g. if the linked module my-module.ko would depend on the symbol myfunc.MY_NS in the namespace MY_NS, the my-module.ns_deps file created by modpost would contain the entry MY_NS to express the namespace dependency of my-module imposed by using the symbol myfunc. These files can subsequently be used by static analysis tools (like coccinelle scripts) to address issues with missing namespace imports. A later patch of this series will introduce such a script 'nsdeps' and a corresponding make target to automatically add missing MODULE_IMPORT_NS() definitions to the module's sources. For that it uses the information provided in the generated .ns_deps files. Co-developed-by: Martijn Coenen Signed-off-by: Martijn Coenen Reviewed-by: Greg Kroah-Hartman Signed-off-by: Matthias Maennich Signed-off-by: Jessica Yu --- .gitignore | 1 + Makefile | 2 +- scripts/mod/modpost.c | 54 ++++++++++++++++++++++++++++++++++++++++++++++----- scripts/mod/modpost.h | 2 ++ 4 files changed, 53 insertions(+), 6 deletions(-) (limited to 'scripts/mod/modpost.h') diff --git a/.gitignore b/.gitignore index 2030c7a4d2f8..9ee63aa2a3fb 100644 --- a/.gitignore +++ b/.gitignore @@ -32,6 +32,7 @@ *.lzo *.mod *.mod.c +*.ns_deps *.o *.o.* *.order diff --git a/Makefile b/Makefile index 0cbe8717bdb3..0cdb957ae2c3 100644 --- a/Makefile +++ b/Makefile @@ -1669,7 +1669,7 @@ clean: $(clean-dirs) -o -name '*.ko.*' \ -o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \ -o -name '*.dwo' -o -name '*.lst' \ - -o -name '*.su' -o -name '*.mod' \ + -o -name '*.su' -o -name '*.mod' -o -name '*.ns_deps' \ -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \ -o -name '*.lex.c' -o -name '*.tab.[ch]' \ -o -name '*.asn1.[ch]' \ diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index c2d49afaea1c..be72da25fe7c 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -38,6 +38,8 @@ static int sec_mismatch_count = 0; static int sec_mismatch_fatal = 0; /* ignore missing files */ static int ignore_missing_files; +/* write namespace dependencies */ +static int write_namespace_deps; enum export { export_plain, export_unused, export_gpl, @@ -2176,10 +2178,15 @@ static int check_exports(struct module *mod) else basename = mod->name; - if (exp->namespace && - !module_imports_namespace(mod, exp->namespace)) { - warn("module %s uses symbol %s from namespace %s, but does not import it.\n", - basename, exp->name, exp->namespace); + if (exp->namespace) { + add_namespace(&mod->required_namespaces, + exp->namespace); + + if (!write_namespace_deps && + !module_imports_namespace(mod, exp->namespace)) { + warn("module %s uses symbol %s from namespace %s, but does not import it.\n", + basename, exp->name, exp->namespace); + } } if (!mod->gpl_compatible) @@ -2484,6 +2491,31 @@ static void write_dump(const char *fname) free(buf.p); } +static void write_namespace_deps_files(void) +{ + struct module *mod; + struct namespace_list *ns; + struct buffer ns_deps_buf = {}; + + for (mod = modules; mod; mod = mod->next) { + char fname[PATH_MAX]; + + if (mod->skip) + continue; + + ns_deps_buf.pos = 0; + + for (ns = mod->required_namespaces; ns; ns = ns->next) + buf_printf(&ns_deps_buf, "%s\n", ns->namespace); + + if (ns_deps_buf.pos == 0) + continue; + + sprintf(fname, "%s.ns_deps", mod->name); + write_if_changed(&ns_deps_buf, fname); + } +} + struct ext_sym_list { struct ext_sym_list *next; const char *file; @@ -2500,7 +2532,7 @@ int main(int argc, char **argv) struct ext_sym_list *extsym_iter; struct ext_sym_list *extsym_start = NULL; - while ((opt = getopt(argc, argv, "i:I:e:mnsT:o:awE")) != -1) { + while ((opt = getopt(argc, argv, "i:I:e:mnsT:o:awEd")) != -1) { switch (opt) { case 'i': kernel_read = optarg; @@ -2541,6 +2573,9 @@ int main(int argc, char **argv) case 'E': sec_mismatch_fatal = 1; break; + case 'd': + write_namespace_deps = 1; + break; default: exit(1); } @@ -2575,6 +2610,9 @@ int main(int argc, char **argv) err |= check_modname_len(mod); err |= check_exports(mod); + if (write_namespace_deps) + continue; + add_header(&buf, mod); add_intree_flag(&buf, !external_module); add_retpoline(&buf); @@ -2587,6 +2625,12 @@ int main(int argc, char **argv) sprintf(fname, "%s.mod.c", mod->name); write_if_changed(&buf, fname); } + + if (write_namespace_deps) { + write_namespace_deps_files(); + return 0; + } + if (dump_write) write_dump(dump_write); if (sec_mismatch_count && sec_mismatch_fatal) diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index 9626bf3e7424..92a926d375d2 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -126,6 +126,8 @@ struct module { struct buffer dev_table_buf; char srcversion[25]; int is_dot_o; + // Required namespace dependencies + struct namespace_list *required_namespaces; // Actual imported namespaces struct namespace_list *imported_namespaces; }; -- cgit v1.2.3