From fa3ba2e81ea23416272a22009bba95954c81969c Mon Sep 17 00:00:00 2001 From: Florin Malita Date: Wed, 11 Oct 2006 01:21:48 -0700 Subject: [PATCH] [PATCH] fix Module taint flags listing in Oops/panic Module taint flags listing in Oops/panic has a couple of issues: * taint_flags() doesn't null-terminate the buffer after printing the flags * per-module taints are only set if the kernel is not already tainted (with that particular flag) => only the first offending module gets its taint info correctly updated Some additional changes: * 'license_gplok' is no longer needed - equivalent to !(taints & TAINT_PROPRIETARY_MODULE) - so we can drop it from struct module * exporting module taint info via /proc/module: pwc 88576 0 - Live 0xf8c32000 evilmod 6784 1 pwc, Live 0xf8bbf000 (PF) Signed-off-by: Florin Malita Cc: "Randy.Dunlap" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/module.h | 3 -- kernel/module.c | 94 ++++++++++++++++++++++-------------------- 2 files changed, 49 insertions(+), 48 deletions(-) diff --git a/include/linux/module.h b/include/linux/module.h index 4b2d8091a410..d1d00ce8f4ed 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -317,9 +317,6 @@ struct module /* Am I unsafe to unload? */ int unsafe; - /* Am I GPL-compatible */ - int license_gplok; - unsigned int taints; /* same bits as kernel:tainted */ #ifdef CONFIG_MODULE_UNLOAD diff --git a/kernel/module.c b/kernel/module.c index 7f60e782de1e..67009bd56c52 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -87,6 +87,12 @@ static inline int strong_try_module_get(struct module *mod) return try_module_get(mod); } +static inline void add_taint_module(struct module *mod, unsigned flag) +{ + add_taint(flag); + mod->taints |= flag; +} + /* A thread that wants to hold a reference to a module only while it * is running can call ths to safely exit. * nfsd and lockd use this. @@ -847,12 +853,10 @@ static int check_version(Elf_Shdr *sechdrs, return 0; } /* Not in module's version table. OK, but that taints the kernel. */ - if (!(tainted & TAINT_FORCED_MODULE)) { + if (!(tainted & TAINT_FORCED_MODULE)) printk("%s: no version for \"%s\" found: kernel tainted.\n", mod->name, symname); - add_taint(TAINT_FORCED_MODULE); - mod->taints |= TAINT_FORCED_MODULE; - } + add_taint_module(mod, TAINT_FORCED_MODULE); return 1; } @@ -910,7 +914,8 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs, unsigned long ret; const unsigned long *crc; - ret = __find_symbol(name, &owner, &crc, mod->license_gplok); + ret = __find_symbol(name, &owner, &crc, + !(mod->taints & TAINT_PROPRIETARY_MODULE)); if (ret) { /* use_module can fail due to OOM, or module unloading */ if (!check_version(sechdrs, versindex, name, mod, crc) || @@ -1335,12 +1340,11 @@ static void set_license(struct module *mod, const char *license) if (!license) license = "unspecified"; - mod->license_gplok = license_is_gpl_compatible(license); - if (!mod->license_gplok && !(tainted & TAINT_PROPRIETARY_MODULE)) { - printk(KERN_WARNING "%s: module license '%s' taints kernel.\n", - mod->name, license); - add_taint(TAINT_PROPRIETARY_MODULE); - mod->taints |= TAINT_PROPRIETARY_MODULE; + if (!license_is_gpl_compatible(license)) { + if (!(tainted & TAINT_PROPRIETARY_MODULE)) + printk(KERN_WARNING "%s: module license '%s' taints" + "kernel.\n", mod->name, license); + add_taint_module(mod, TAINT_PROPRIETARY_MODULE); } } @@ -1619,8 +1623,7 @@ static struct module *load_module(void __user *umod, modmagic = get_modinfo(sechdrs, infoindex, "vermagic"); /* This is allowed: modprobe --force will invalidate it. */ if (!modmagic) { - add_taint(TAINT_FORCED_MODULE); - mod->taints |= TAINT_FORCED_MODULE; + add_taint_module(mod, TAINT_FORCED_MODULE); printk(KERN_WARNING "%s: no version magic, tainting kernel.\n", mod->name); } else if (!same_magic(modmagic, vermagic)) { @@ -1714,14 +1717,10 @@ static struct module *load_module(void __user *umod, /* Set up license info based on the info section */ set_license(mod, get_modinfo(sechdrs, infoindex, "license")); - if (strcmp(mod->name, "ndiswrapper") == 0) { - add_taint(TAINT_PROPRIETARY_MODULE); - mod->taints |= TAINT_PROPRIETARY_MODULE; - } - if (strcmp(mod->name, "driverloader") == 0) { - add_taint(TAINT_PROPRIETARY_MODULE); - mod->taints |= TAINT_PROPRIETARY_MODULE; - } + if (strcmp(mod->name, "ndiswrapper") == 0) + add_taint_module(mod, TAINT_PROPRIETARY_MODULE); + if (strcmp(mod->name, "driverloader") == 0) + add_taint_module(mod, TAINT_PROPRIETARY_MODULE); /* Set up MODINFO_ATTR fields */ setup_modinfo(mod, sechdrs, infoindex); @@ -1766,8 +1765,7 @@ static struct module *load_module(void __user *umod, (mod->num_unused_gpl_syms && !unusedgplcrcindex)) { printk(KERN_WARNING "%s: No versions for exported symbols." " Tainting kernel.\n", mod->name); - add_taint(TAINT_FORCED_MODULE); - mod->taints |= TAINT_FORCED_MODULE; + add_taint_module(mod, TAINT_FORCED_MODULE); } #endif @@ -2132,9 +2130,33 @@ static void m_stop(struct seq_file *m, void *p) mutex_unlock(&module_mutex); } +static char *taint_flags(unsigned int taints, char *buf) +{ + int bx = 0; + + if (taints) { + buf[bx++] = '('; + if (taints & TAINT_PROPRIETARY_MODULE) + buf[bx++] = 'P'; + if (taints & TAINT_FORCED_MODULE) + buf[bx++] = 'F'; + /* + * TAINT_FORCED_RMMOD: could be added. + * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't + * apply to modules. + */ + buf[bx++] = ')'; + } + buf[bx] = '\0'; + + return buf; +} + static int m_show(struct seq_file *m, void *p) { struct module *mod = list_entry(p, struct module, list); + char buf[8]; + seq_printf(m, "%s %lu", mod->name, mod->init_size + mod->core_size); print_unload_info(m, mod); @@ -2147,6 +2169,10 @@ static int m_show(struct seq_file *m, void *p) /* Used by oprofile and other similar tools. */ seq_printf(m, " 0x%p", mod->module_core); + /* Taints info */ + if (mod->taints) + seq_printf(m, " %s", taint_flags(mod->taints, buf)); + seq_printf(m, "\n"); return 0; } @@ -2235,28 +2261,6 @@ struct module *module_text_address(unsigned long addr) return mod; } -static char *taint_flags(unsigned int taints, char *buf) -{ - *buf = '\0'; - if (taints) { - int bx; - - buf[0] = '('; - bx = 1; - if (taints & TAINT_PROPRIETARY_MODULE) - buf[bx++] = 'P'; - if (taints & TAINT_FORCED_MODULE) - buf[bx++] = 'F'; - /* - * TAINT_FORCED_RMMOD: could be added. - * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't - * apply to modules. - */ - buf[bx] = ')'; - } - return buf; -} - /* Don't grab lock, we're oopsing. */ void print_modules(void) {