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author | Prarit Bhargava <prarit@redhat.com> | 2016-07-21 08:07:56 +0200 |
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committer | Rusty Russell <rusty@rustcorp.com.au> | 2016-08-04 02:46:53 +0200 |
commit | be7de5f91fdc3a63ee01910c43f20db213445ce4 (patch) | |
tree | bce5a3b202a589e962cffa2f8dec3d58fbbddbc7 /kernel/module.c | |
parent | module: Do a WARN_ON_ONCE() for assert module mutex not held (diff) | |
download | linux-be7de5f91fdc3a63ee01910c43f20db213445ce4.tar.xz linux-be7de5f91fdc3a63ee01910c43f20db213445ce4.zip |
modules: Add kernel parameter to blacklist modules
Blacklisting a module in linux has long been a problem. The current
procedure is to use rd.blacklist=module_name, however, that doesn't
cover the case after the initramfs and before a boot prompt (where one
is supposed to use /etc/modprobe.d/blacklist.conf to blacklist
runtime loading). Using rd.shell to get an early prompt is hit-or-miss,
and doesn't cover all situations AFAICT.
This patch adds this functionality of permanently blacklisting a module
by its name via the kernel parameter module_blacklist=module_name.
[v2]: Rusty, use core_param() instead of __setup() which simplifies
things.
[v3]: Rusty, undo wreckage from strsep()
[v4]: Rusty, simpler version of blacklisted()
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: linux-doc@vger.kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Diffstat (limited to 'kernel/module.c')
-rw-r--r-- | kernel/module.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/kernel/module.c b/kernel/module.c index beaebea627ff..c91c2fdca2e6 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3168,6 +3168,27 @@ int __weak module_frob_arch_sections(Elf_Ehdr *hdr, return 0; } +/* module_blacklist is a comma-separated list of module names */ +static char *module_blacklist; +static bool blacklisted(char *module_name) +{ + const char *p; + size_t len; + + if (!module_blacklist) + return false; + + for (p = module_blacklist; *p; p += len) { + len = strcspn(p, ","); + if (strlen(module_name) == len && !memcmp(module_name, p, len)) + return true; + if (p[len] == ',') + len++; + } + return false; +} +core_param(module_blacklist, module_blacklist, charp, 0400); + static struct module *layout_and_allocate(struct load_info *info, int flags) { /* Module within temporary copy. */ @@ -3178,6 +3199,9 @@ static struct module *layout_and_allocate(struct load_info *info, int flags) if (IS_ERR(mod)) return mod; + if (blacklisted(mod->name)) + return ERR_PTR(-EPERM); + err = check_modinfo(mod, info, flags); if (err) return ERR_PTR(err); |