From 9841d61d75da5e46ed7a978bed4f50c78b1d87fd Mon Sep 17 00:00:00 2001 From: Dave Jones Date: Sun, 8 Jan 2006 01:03:41 -0800 Subject: [PATCH] Add tainting for proprietary helper modules Kernels that have had Windows drivers loaded into them are undebuggable. I've wasted a number of hours chasing bugs filed in Fedora bugzilla only to find out much later that the user had used such 'helpers', and their problems were unreproducable without them loaded. Acked-by: Arjan van de Ven Signed-off-by: Dave Jones Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/module.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index 4b06bbad49c2..5d9078d6f0fa 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1715,6 +1715,11 @@ 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); + if (strcmp(mod->name, "driverloader") == 0) + add_taint(TAINT_PROPRIETARY_MODULE); + #ifdef CONFIG_MODULE_UNLOAD /* Set up MODINFO_ATTR fields */ setup_modinfo(mod, sechdrs, infoindex); -- cgit v1.2.3 From eea8b54dc0dceb740da697a89c54d20dde340306 Mon Sep 17 00:00:00 2001 From: Ashutosh Naik Date: Sun, 8 Jan 2006 01:04:25 -0800 Subject: [PATCH] modules: prevent overriding of symbols Ensure that an exported symbol does not already exist in the kernel or in some other module's exported symbol table. This is done by checking the symbol tables for the exported symbol at the time of loading the module. Currently this is done after the relocation of the symbol. Signed-off-by: Ashutosh Naik Signed-off-by: Anand Krishnan Cc: Rusty Russell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/module.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index 5d9078d6f0fa..fb6f091f5940 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1204,6 +1204,39 @@ void *__symbol_get(const char *symbol) } EXPORT_SYMBOL_GPL(__symbol_get); +/* + * Ensure that an exported symbol [global namespace] does not already exist + * in the Kernel or in some other modules exported symbol table. + */ +static int verify_export_symbols(struct module *mod) +{ + const char *name = NULL; + unsigned long i, ret = 0; + struct module *owner; + const unsigned long *crc; + + for (i = 0; i < mod->num_syms; i++) + if (__find_symbol(mod->syms[i].name, &owner, &crc, 1)) { + name = mod->syms[i].name; + ret = -ENOEXEC; + goto dup; + } + + for (i = 0; i < mod->num_gpl_syms; i++) + if (__find_symbol(mod->gpl_syms[i].name, &owner, &crc, 1)) { + name = mod->gpl_syms[i].name; + ret = -ENOEXEC; + goto dup; + } + +dup: + if (ret) + printk(KERN_ERR "%s: exports duplicate symbol %s (owned by %s)\n", + mod->name, name, module_name(owner)); + + return ret; +} + /* Change all symbols so that sh_value encodes the pointer directly. */ static int simplify_symbols(Elf_Shdr *sechdrs, unsigned int symindex, @@ -1772,6 +1805,12 @@ static struct module *load_module(void __user *umod, goto cleanup; } + /* Find duplicate symbols */ + err = verify_export_symbols(mod); + + if (err < 0) + goto cleanup; + /* Set up and sort exception table */ mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable); mod->extable = extable = (void *)sechdrs[exindex].sh_addr; -- cgit v1.2.3 From fb1697933a03ec47d794b38e2a4e3ccc2463fd22 Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Sun, 8 Jan 2006 01:04:29 -0800 Subject: [PATCH] modules: mark TAINT_FORCED_RMMOD correctly Currently TAINT_FORCED_RMMOD is totally unused. Because it is marked as TAINT_FORCED_MODULE instead when user forced a module unload. This patch marks it correctly Signed-off-by: Akinobu Mita Cc: Rusty Russell Cc: Dave Jones Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/module.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index fb6f091f5940..f368812ac0e8 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -496,15 +496,15 @@ static void module_unload_free(struct module *mod) } #ifdef CONFIG_MODULE_FORCE_UNLOAD -static inline int try_force(unsigned int flags) +static inline int try_force_unload(unsigned int flags) { int ret = (flags & O_TRUNC); if (ret) - add_taint(TAINT_FORCED_MODULE); + add_taint(TAINT_FORCED_RMMOD); return ret; } #else -static inline int try_force(unsigned int flags) +static inline int try_force_unload(unsigned int flags) { return 0; } @@ -524,7 +524,7 @@ static int __try_stop_module(void *_sref) /* If it's not unused, quit unless we are told to block. */ if ((sref->flags & O_NONBLOCK) && module_refcount(sref->mod) != 0) { - if (!(*sref->forced = try_force(sref->flags))) + if (!(*sref->forced = try_force_unload(sref->flags))) return -EWOULDBLOCK; } @@ -609,7 +609,7 @@ sys_delete_module(const char __user *name_user, unsigned int flags) /* If it has an init func, it must have an exit func to unload */ if ((mod->init != NULL && mod->exit == NULL) || mod->unsafe) { - forced = try_force(flags); + forced = try_force_unload(flags); if (!forced) { /* This module can't be removed */ ret = -EBUSY; -- cgit v1.2.3 From eb46996f90a0826921f1a0d81535537a9c7f91b0 Mon Sep 17 00:00:00 2001 From: Ashutosh Naik Date: Sun, 8 Jan 2006 01:04:37 -0800 Subject: [PATCH] kernel/module.c: remove redundant spinlock in resolve_symbol() Remove the redundant spinlock in the function resolve_symbol() as we are not altering the module list, and we already hold the semaphore. Signed-off-by: Ashutosh Naik Cc: Rusty Russell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/module.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index f368812ac0e8..e4276046a1b6 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -958,7 +958,6 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs, unsigned long ret; const unsigned long *crc; - spin_lock_irq(&modlist_lock); ret = __find_symbol(name, &owner, &crc, mod->license_gplok); if (ret) { /* use_module can fail due to OOM, or module unloading */ @@ -966,7 +965,6 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs, !use_module(mod, owner)) ret = 0; } - spin_unlock_irq(&modlist_lock); return ret; } -- cgit v1.2.3