From 94f7683c5a5084b61756c6df29c14041efebcd94 Mon Sep 17 00:00:00 2001 From: Lucas De Marchi Date: Tue, 15 Feb 2022 23:36:49 -0800 Subject: modinfo: Allow to force arg as module name If the Linux kernel or userspace sets an alias with the same name as a module, they force the tools to use that. However in some situations it may be desired to query the module itself. Getting the module information through modinfo is one such situation. So, add a option to modinfo to explicitly instruct it to handle the argument as a module name. Example, when trying to output information about the crc32 module that is builtin: $ modinfo crc32 filename: /lib/modules/5.15.19-1-MANJARO/kernel/arch/x86/crypto/crc32-pclmul.ko.zst alias: crypto-crc32-pclmul alias: crc32-pclmul alias: crypto-crc32 alias: crc32 license: GPL author: Alexander Boyko srcversion: B6B2FF9236731E69418A2E5 alias: cpu:type:x86,ven*fam*mod*:feature:*0081* depends: retpoline: Y intree: Y name: crc32_pclmul vermagic: 5.15.19-1-MANJARO SMP preempt mod_unload sig_id: PKCS#7 signer: Build time autogenerated kernel key sig_key: 77:FB:AA:BD:48:78:A4:C6:56:18:9A:7E:A6:F3:29:3E:C5:6B:E9:37 sig_hashalgo: sha512 signature: 30:65:02:31:00:B0:D4:49:9D:1D:F1:71:4C:3C:BB:70:B2:3E:46:5D: 38:5A:F1:00:95:FD:7A:96:C4:2C:24:35:A2:1B:0B:A8:1C:29:6F:02: 7A:68:EE:BA:A4:1C:01:4B:86:39:15:3E:66:02:30:7F:7A:66:5E:F2: 2F:98:73:3D:AD:96:66:81:8B:94:6E:F3:3F:44:0F:85:E1:73:3A:9E: F9:C4:BE:9B:88:02:BD:83:04:B9:2E:72:0B:93:BC:82:B6:A1:1B:6A: C2:ED:8C filename: /lib/modules/5.15.19-1-MANJARO/kernel/crypto/crc32_generic.ko.zst alias: crypto-crc32-generic alias: crc32-generic alias: crypto-crc32 alias: crc32 license: GPL description: CRC32 calculations wrapper for lib/crc32 author: Alexander Boyko srcversion: F08036C38DDB06BCD1E6091 depends: retpoline: Y intree: Y name: crc32_generic vermagic: 5.15.19-1-MANJARO SMP preempt mod_unload sig_id: PKCS#7 signer: Build time autogenerated kernel key sig_key: 77:FB:AA:BD:48:78:A4:C6:56:18:9A:7E:A6:F3:29:3E:C5:6B:E9:37 sig_hashalgo: sha512 signature: 30:65:02:31:00:E3:9E:C8:80:15:0E:D7:74:96:B5:25:EA:32:F7:DF: E9:FC:3C:82:D9:B9:B9:37:C5:20:8D:06:31:02:62:B3:54:E8:DF:F2: 7E:E2:7C:A4:CF:49:17:CB:75:DF:2C:7A:2F:02:30:25:DE:7C:2A:2C: 97:3F:65:16:76:B3:71:FB:62:DB:8F:F3:33:65:77:98:F3:57:ED:D7: 87:78:FF:C2:04:55:70:00:10:63:1E:B2:FE:22:D8:E5:6D:5F:95:4E: 7D:2C:6B That is because the Linux kernel exports "crc32" as an alias to those modules, besides being a module itself: $ grep crc32 /lib/modules/$(uname -r)/modules.builtin kernel/lib/crc32.ko $ $ grep "alias crc32 " /lib/modules/$(uname -r)/modules.alias alias crc32 crc32_pclmul alias crc32 crc32_generic With the new -m|--modname option it's possible to query the information about this (builtin) module explicitly: $ modinfo --modname crc32 name: crc32 filename: (builtin) license: GPL file: lib/crc32 description: Various CRC32 calculations author: Matt Domsch Reviewed-by: Luis Chamberlain --- tools/modinfo.c | 30 ++++++++++++++++++++++++++++-- 1 file changed, 28 insertions(+), 2 deletions(-) diff --git a/tools/modinfo.c b/tools/modinfo.c index f51b7e4..d0aab20 100644 --- a/tools/modinfo.c +++ b/tools/modinfo.c @@ -293,6 +293,24 @@ static int modinfo_path_do(struct kmod_ctx *ctx, const char *path) return err; } +static int modinfo_name_do(struct kmod_ctx *ctx, const char *name) +{ + struct kmod_module *mod = NULL; + int err; + + err = kmod_module_new_from_name_lookup(ctx, name, &mod); + if (err < 0 || mod == NULL) { + ERR("Module name %s not found.\n", name); + return err < 0 ? err : -ENOENT; + } + + err = modinfo_do(mod); + kmod_module_unref(mod); + + return err; +} + + static int modinfo_alias_do(struct kmod_ctx *ctx, const char *alias) { struct kmod_list *l, *list = NULL; @@ -318,7 +336,7 @@ static int modinfo_alias_do(struct kmod_ctx *ctx, const char *alias) return err; } -static const char cmdopts_s[] = "adlpn0F:k:b:Vh"; +static const char cmdopts_s[] = "adlpn0mF:k:b:Vh"; static const struct option cmdopts[] = { {"author", no_argument, 0, 'a'}, {"description", no_argument, 0, 'd'}, @@ -326,6 +344,7 @@ static const struct option cmdopts[] = { {"parameters", no_argument, 0, 'p'}, {"filename", no_argument, 0, 'n'}, {"null", no_argument, 0, '0'}, + {"modname", no_argument, 0, 'm'}, {"field", required_argument, 0, 'F'}, {"set-version", required_argument, 0, 'k'}, {"basedir", required_argument, 0, 'b'}, @@ -345,6 +364,7 @@ static void help(void) "\t-p, --parameters Print only 'parm'\n" "\t-n, --filename Print only 'filename'\n" "\t-0, --null Use \\0 instead of \\n\n" + "\t-m, --modname Handle argument as module name instead of alias or filename\n" "\t-F, --field=FIELD Print only provided FIELD\n" "\t-k, --set-version=VERSION Use VERSION instead of `uname -r`\n" "\t-b, --basedir=DIR Use DIR as filesystem root for /lib/modules\n" @@ -372,6 +392,7 @@ static int do_modinfo(int argc, char *argv[]) const char *kversion = NULL; const char *root = NULL; const char *null_config = NULL; + bool arg_is_modname = false; int i, err; for (;;) { @@ -398,6 +419,9 @@ static int do_modinfo(int argc, char *argv[]) case '0': separator = '\0'; break; + case 'm': + arg_is_modname = true; + break; case 'F': field = optarg; break; @@ -454,7 +478,9 @@ static int do_modinfo(int argc, char *argv[]) const char *name = argv[i]; int r; - if (is_module_filename(name)) + if (arg_is_modname) + r = modinfo_name_do(ctx, name); + else if (is_module_filename(name)) r = modinfo_path_do(ctx, name); else r = modinfo_alias_do(ctx, name); -- cgit v1.2.1