From 1cd0d6c3021c8d76641b37203f504634b87fbabc Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Tue, 1 Nov 2011 03:59:33 +0000 Subject: module: Enable dynamic debugging regardless of taint Dynamic debugging is currently disabled for tainted modules, except for TAINT_CRAP. This prevents use of dynamic debugging for out-of-tree modules once the next patch is applied. This condition was apparently intended to avoid a crash if a force- loaded module has an incompatible definition of dynamic debug structures. However, a administrator that forces us to load a module is claiming that it *is* compatible even though it fails our version checks. If they are mistaken, there are any number of ways the module could crash the system. As a side-effect, proprietary and other tainted modules can now use dynamic_debug. Signed-off-by: Ben Hutchings Acked-by: Mathieu Desnoyers Signed-off-by: Rusty Russell --- kernel/module.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/kernel/module.c b/kernel/module.c index 93342d992f34..3c5509642847 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2878,8 +2878,7 @@ static struct module *load_module(void __user *umod, } /* This has to be done once we're sure module name is unique. */ - if (!mod->taints || mod->taints == (1U<taints || mod->taints == (1U< Date: Mon, 24 Oct 2011 15:12:28 +0200 Subject: module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree Use of the GPL or a compatible licence doesn't necessarily make the code any good. We already consider staging modules to be suspect, and this should also be true for out-of-tree modules which may receive very little review. Signed-off-by: Ben Hutchings Reviewed-by: Dave Jones Acked-by: Greg Kroah-Hartman Signed-off-by: Rusty Russell (patched oops-tracing.txt) --- Documentation/oops-tracing.txt | 2 ++ include/linux/kernel.h | 1 + kernel/module.c | 5 +++++ kernel/panic.c | 2 ++ scripts/mod/modpost.c | 7 +++++++ 5 files changed, 17 insertions(+) diff --git a/Documentation/oops-tracing.txt b/Documentation/oops-tracing.txt index 6fe9001b9263..13032c0140d4 100644 --- a/Documentation/oops-tracing.txt +++ b/Documentation/oops-tracing.txt @@ -263,6 +263,8 @@ characters, each representing a particular tainted value. 12: 'I' if the kernel is working around a severe bug in the platform firmware (BIOS or similar). + 13: 'O' if an externally-built ("out-of-tree") module has been loaded. + The primary reason for the 'Tainted: ' string is to tell kernel debuggers if this is a clean kernel or if anything unusual has occurred. Tainting is permanent: even if an offending module is diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 4c0d3b2fd5fc..e8b1597b5cf2 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -371,6 +371,7 @@ extern enum system_states { #define TAINT_WARN 9 #define TAINT_CRAP 10 #define TAINT_FIRMWARE_WORKAROUND 11 +#define TAINT_OOT_MODULE 12 extern const char hex_asc[]; #define hex_asc_lo(x) hex_asc[((x) & 0x0f)] diff --git a/kernel/module.c b/kernel/module.c index 3c5509642847..ef8cb70c6996 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2487,6 +2487,9 @@ static int check_modinfo(struct module *mod, struct load_info *info) return -ENOEXEC; } + if (!get_modinfo(info, "intree")) + add_taint_module(mod, TAINT_OOT_MODULE); + if (get_modinfo(info, "staging")) { add_taint_module(mod, TAINT_CRAP); printk(KERN_WARNING "%s: module is from the staging directory," @@ -3255,6 +3258,8 @@ static char *module_flags(struct module *mod, char *buf) buf[bx++] = '('; if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE)) buf[bx++] = 'P'; + else if (mod->taints & (1 << TAINT_OOT_MODULE)) + buf[bx++] = 'O'; if (mod->taints & (1 << TAINT_FORCED_MODULE)) buf[bx++] = 'F'; if (mod->taints & (1 << TAINT_CRAP)) diff --git a/kernel/panic.c b/kernel/panic.c index d7bb6974efb5..b26593604214 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -177,6 +177,7 @@ static const struct tnt tnts[] = { { TAINT_WARN, 'W', ' ' }, { TAINT_CRAP, 'C', ' ' }, { TAINT_FIRMWARE_WORKAROUND, 'I', ' ' }, + { TAINT_OOT_MODULE, 'O', ' ' }, }; /** @@ -194,6 +195,7 @@ static const struct tnt tnts[] = { * 'W' - Taint on warning. * 'C' - modules from drivers/staging are loaded. * 'I' - Working around severe firmware bug. + * 'O' - Out-of-tree module has been loaded. * * The string is overwritten by the next call to print_tainted(). */ diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index a509ff8f32fa..2bd594e6d1b4 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1849,6 +1849,12 @@ static void add_header(struct buffer *b, struct module *mod) buf_printf(b, "};\n"); } +static void add_intree_flag(struct buffer *b, int is_intree) +{ + if (is_intree) + buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n"); +} + static void add_staging_flag(struct buffer *b, const char *name) { static const char *staging_dir = "drivers/staging"; @@ -2169,6 +2175,7 @@ int main(int argc, char **argv) buf.pos = 0; add_header(&buf, mod); + add_intree_flag(&buf, !external_module); add_staging_flag(&buf, mod->name); err |= add_versions(&buf, mod); add_depends(&buf, mod, modules); -- cgit v1.2.3