diff options
author | Matthias Maennich <maennich@google.com> | 2019-09-06 13:32:29 +0300 |
---|---|---|
committer | Jessica Yu <jeyu@kernel.org> | 2019-09-10 11:30:27 +0300 |
commit | 3d52ec5e5d0dd7f8ca96a68c6756bd96e58b716b (patch) | |
tree | 51b5da97980203a40b9b1393ec5da9157d4d3215 | |
parent | cb9b55d21fe06ca5e4ba244bb5aac0afeb745c8e (diff) | |
download | linux-3d52ec5e5d0dd7f8ca96a68c6756bd96e58b716b.tar.xz |
module: add config option MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
If MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS is enabled (default=n), the
requirement for modules to import all namespaces that are used by
the module is relaxed.
Enabling this option effectively allows (invalid) modules to be loaded
while only a warning is emitted.
Disabling this option keeps the enforcement at module loading time and
loading is denied if the module's imports are not satisfactory.
Reviewed-by: Martijn Coenen <maco@android.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Matthias Maennich <maennich@google.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
-rw-r--r-- | init/Kconfig | 13 | ||||
-rw-r--r-- | kernel/module.c | 11 |
2 files changed, 22 insertions, 2 deletions
diff --git a/init/Kconfig b/init/Kconfig index bd7d650d4a99..cc28561288a7 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -2119,6 +2119,19 @@ config MODULE_COMPRESS_XZ endchoice +config MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS + bool "Allow loading of modules with missing namespace imports" + help + Symbols exported with EXPORT_SYMBOL_NS*() are considered exported in + a namespace. A module that makes use of a symbol exported with such a + namespace is required to import the namespace via MODULE_IMPORT_NS(). + There is no technical reason to enforce correct namespace imports, + but it creates consistency between symbols defining namespaces and + users importing namespaces they make use of. This option relaxes this + requirement and lifts the enforcement when loading a module. + + If unsure, say N. + config TRIM_UNUSED_KSYMS bool "Trim unused exported kernel symbols" depends on MODULES && !UNUSED_SYMBOLS diff --git a/kernel/module.c b/kernel/module.c index 6bb9b938f9c7..f76efcf2043e 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1408,9 +1408,16 @@ static int verify_namespace_is_imported(const struct load_info *info, imported_namespace = get_next_modinfo( info, "import_ns", imported_namespace); } - pr_err("%s: module uses symbol (%s) from namespace %s, but does not import it.\n", - mod->name, kernel_symbol_name(sym), namespace); +#ifdef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS + pr_warn( +#else + pr_err( +#endif + "%s: module uses symbol (%s) from namespace %s, but does not import it.\n", + mod->name, kernel_symbol_name(sym), namespace); +#ifndef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS return -EINVAL; +#endif } return 0; } |