diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-02-23 10:15:33 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-02-23 10:15:33 -0800 |
commit | 21a6ab2131ab0644eeef70507e20273338bf065c (patch) | |
tree | 6161fed2e5a5e2341d736f85a5f8f0acb8c93e80 | |
parent | 74268693e0f751381688743a48e37cf63a45deef (diff) | |
parent | 1e80d9cb579ed7edd121753eeccce82ff82521b4 (diff) |
Merge tag 'modules-for-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull module updates from Jessica Yu:
- Retire EXPORT_UNUSED_SYMBOL() and EXPORT_SYMBOL_GPL_FUTURE(). These
export types were introduced between 2006 - 2008. All the of the
unused symbols have been long removed and gpl future symbols were
converted to gpl quite a long time ago, and I don't believe these
export types have been used ever since. So, I think it should be safe
to retire those export types now (Christoph Hellwig)
- Refactor and clean up some aged code cruft in the module loader
(Christoph Hellwig)
- Build {,module_}kallsyms_on_each_symbol only when livepatching is
enabled, as it is the only caller (Christoph Hellwig)
- Unexport find_module() and module_mutex and fix the last module
callers to not rely on these anymore. Make module_mutex internal to
the module loader (Christoph Hellwig)
- Harden ELF checks on module load and validate ELF structures before
checking the module signature (Frank van der Linden)
- Fix undefined symbol warning for clang (Fangrui Song)
- Fix smatch warning (Dan Carpenter)
* tag 'modules-for-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
module: potential uninitialized return in module_kallsyms_on_each_symbol()
module: remove EXPORT_UNUSED_SYMBOL*
module: remove EXPORT_SYMBOL_GPL_FUTURE
module: move struct symsearch to module.c
module: pass struct find_symbol_args to find_symbol
module: merge each_symbol_section into find_symbol
module: remove each_symbol_in_section
module: mark module_mutex static
kallsyms: only build {,module_}kallsyms_on_each_symbol when required
kallsyms: refactor {,module_}kallsyms_on_each_symbol
module: use RCU to synchronize find_module
module: unexport find_module and module_mutex
drm: remove drm_fb_helper_modinit
powerpc/powernv: remove get_cxl_module
module: harden ELF info handling
module: Ignore _GLOBAL_OFFSET_TABLE_ when warning for undefined symbols
35 files changed, 287 insertions, 516 deletions
diff --git a/arch/arm/configs/bcm2835_defconfig b/arch/arm/configs/bcm2835_defconfig index 1ef2bc4c7f69..383c632eba7b 100644 --- a/arch/arm/configs/bcm2835_defconfig +++ b/arch/arm/configs/bcm2835_defconfig @@ -176,7 +176,6 @@ CONFIG_BOOT_PRINTK_DELAY=y CONFIG_DYNAMIC_DEBUG=y CONFIG_DEBUG_INFO=y # CONFIG_ENABLE_MUST_CHECK is not set -CONFIG_UNUSED_SYMBOLS=y CONFIG_DEBUG_MEMORY_INIT=y CONFIG_LOCKUP_DETECTOR=y CONFIG_SCHED_TRACER=y diff --git a/arch/arm/configs/mxs_defconfig b/arch/arm/configs/mxs_defconfig index a9c6f32a9b1c..ca32446b187f 100644 --- a/arch/arm/configs/mxs_defconfig +++ b/arch/arm/configs/mxs_defconfig @@ -164,7 +164,6 @@ CONFIG_FONTS=y CONFIG_PRINTK_TIME=y CONFIG_DEBUG_INFO=y CONFIG_FRAME_WARN=2048 -CONFIG_UNUSED_SYMBOLS=y CONFIG_MAGIC_SYSRQ=y CONFIG_DEBUG_KERNEL=y CONFIG_SOFTLOCKUP_DETECTOR=y diff --git a/arch/mips/configs/nlm_xlp_defconfig b/arch/mips/configs/nlm_xlp_defconfig index 72a211d2d556..32c290611723 100644 --- a/arch/mips/configs/nlm_xlp_defconfig +++ b/arch/mips/configs/nlm_xlp_defconfig @@ -549,7 +549,6 @@ CONFIG_PRINTK_TIME=y CONFIG_DEBUG_INFO=y # CONFIG_ENABLE_MUST_CHECK is not set CONFIG_FRAME_WARN=1024 -CONFIG_UNUSED_SYMBOLS=y CONFIG_DEBUG_MEMORY_INIT=y CONFIG_DETECT_HUNG_TASK=y CONFIG_SCHEDSTATS=y diff --git a/arch/mips/configs/nlm_xlr_defconfig b/arch/mips/configs/nlm_xlr_defconfig index 4ecb157e56d4..bf9b9244929e 100644 --- a/arch/mips/configs/nlm_xlr_defconfig +++ b/arch/mips/configs/nlm_xlr_defconfig @@ -500,7 +500,6 @@ CONFIG_CRC7=m CONFIG_PRINTK_TIME=y CONFIG_DEBUG_INFO=y # CONFIG_ENABLE_MUST_CHECK is not set -CONFIG_UNUSED_SYMBOLS=y CONFIG_DEBUG_MEMORY_INIT=y CONFIG_DETECT_HUNG_TASK=y CONFIG_SCHEDSTATS=y diff --git a/arch/parisc/configs/generic-32bit_defconfig b/arch/parisc/configs/generic-32bit_defconfig index 3cbcfad5f724..7611d48c599e 100644 --- a/arch/parisc/configs/generic-32bit_defconfig +++ b/arch/parisc/configs/generic-32bit_defconfig @@ -22,7 +22,6 @@ CONFIG_PCI_LBA=y CONFIG_MODULES=y CONFIG_MODULE_UNLOAD=y CONFIG_MODULE_FORCE_UNLOAD=y -CONFIG_UNUSED_SYMBOLS=y # CONFIG_BLK_DEV_BSG is not set # CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS is not set CONFIG_BINFMT_MISC=m diff --git a/arch/parisc/configs/generic-64bit_defconfig b/arch/parisc/configs/generic-64bit_defconfig index 8f81fcbf04c4..53054b81461a 100644 --- a/arch/parisc/configs/generic-64bit_defconfig +++ b/arch/parisc/configs/generic-64bit_defconfig @@ -31,7 +31,6 @@ CONFIG_MODULE_FORCE_LOAD=y CONFIG_MODULE_UNLOAD=y CONFIG_MODULE_FORCE_UNLOAD=y CONFIG_MODVERSIONS=y -CONFIG_UNUSED_SYMBOLS=y CONFIG_BLK_DEV_INTEGRITY=y CONFIG_BINFMT_MISC=m # CONFIG_COMPACTION is not set diff --git a/arch/powerpc/configs/ppc6xx_defconfig b/arch/powerpc/configs/ppc6xx_defconfig index 10c055eaebf0..6677ac0da45a 100644 --- a/arch/powerpc/configs/ppc6xx_defconfig +++ b/arch/powerpc/configs/ppc6xx_defconfig @@ -1071,7 +1071,6 @@ CONFIG_NLS_ISO8859_15=m CONFIG_NLS_KOI8_R=m CONFIG_NLS_KOI8_U=m CONFIG_DEBUG_INFO=y -CONFIG_UNUSED_SYMBOLS=y CONFIG_HEADERS_INSTALL=y CONFIG_MAGIC_SYSRQ=y CONFIG_DEBUG_KERNEL=y diff --git a/arch/powerpc/platforms/powernv/pci-cxl.c b/arch/powerpc/platforms/powernv/pci-cxl.c index 8c739c94ed28..53172862d23b 100644 --- a/arch/powerpc/platforms/powernv/pci-cxl.c +++ b/arch/powerpc/platforms/powernv/pci-cxl.c @@ -150,25 +150,3 @@ int pnv_cxl_ioda_msi_setup(struct pci_dev *dev, unsigned int hwirq, return 0; } EXPORT_SYMBOL(pnv_cxl_ioda_msi_setup); - -#if IS_MODULE(CONFIG_CXL) -static inline int get_cxl_module(void) -{ - struct module *cxl_module; - - mutex_lock(&module_mutex); - - cxl_module = find_module("cxl"); - if (cxl_module) - __module_get(cxl_module); - - mutex_unlock(&module_mutex); - - if (!cxl_module) - return -ENODEV; - - return 0; -} -#else -static inline int get_cxl_module(void) { return 0; } -#endif diff --git a/arch/s390/configs/debug_defconfig b/arch/s390/configs/debug_defconfig index 6896b4213c49..02056b024091 100644 --- a/arch/s390/configs/debug_defconfig +++ b/arch/s390/configs/debug_defconfig @@ -71,7 +71,6 @@ CONFIG_MODULE_FORCE_UNLOAD=y CONFIG_MODVERSIONS=y CONFIG_MODULE_SRCVERSION_ALL=y CONFIG_MODULE_SIG_SHA256=y -CONFIG_UNUSED_SYMBOLS=y CONFIG_BLK_DEV_INTEGRITY=y CONFIG_BLK_DEV_THROTTLING=y CONFIG_BLK_WBT=y diff --git a/arch/s390/configs/defconfig b/arch/s390/configs/defconfig index ef4df9d60d6a..bac721a501da 100644 --- a/arch/s390/configs/defconfig +++ b/arch/s390/configs/defconfig @@ -66,7 +66,6 @@ CONFIG_MODULE_FORCE_UNLOAD=y CONFIG_MODVERSIONS=y CONFIG_MODULE_SRCVERSION_ALL=y CONFIG_MODULE_SIG_SHA256=y -CONFIG_UNUSED_SYMBOLS=y CONFIG_BLK_DEV_THROTTLING=y CONFIG_BLK_WBT=y CONFIG_BLK_CGROUP_IOLATENCY=y diff --git a/arch/sh/configs/edosk7760_defconfig b/arch/sh/configs/edosk7760_defconfig index 02ba62298576..d77f54e906fd 100644 --- a/arch/sh/configs/edosk7760_defconfig +++ b/arch/sh/configs/edosk7760_defconfig @@ -102,7 +102,6 @@ CONFIG_NLS_UTF8=y CONFIG_PRINTK_TIME=y # CONFIG_ENABLE_MUST_CHECK is not set CONFIG_MAGIC_SYSRQ=y -CONFIG_UNUSED_SYMBOLS=y CONFIG_DEBUG_KERNEL=y CONFIG_DEBUG_SHIRQ=y CONFIG_DETECT_HUNG_TASK=y diff --git a/arch/sh/configs/sdk7780_defconfig b/arch/sh/configs/sdk7780_defconfig index d00376eb044f..6c719ab4332a 100644 --- a/arch/sh/configs/sdk7780_defconfig +++ b/arch/sh/configs/sdk7780_defconfig @@ -128,7 +128,6 @@ CONFIG_NLS_ISO8859_15=y CONFIG_NLS_UTF8=y # CONFIG_ENABLE_MUST_CHECK is not set CONFIG_MAGIC_SYSRQ=y -CONFIG_UNUSED_SYMBOLS=y CONFIG_DEBUG_KERNEL=y CONFIG_DETECT_HUNG_TASK=y # CONFIG_SCHED_DEBUG is not set diff --git a/arch/x86/configs/i386_defconfig b/arch/x86/configs/i386_defconfig index 78210793d357..9c9c4a888b1d 100644 --- a/arch/x86/configs/i386_defconfig +++ b/arch/x86/configs/i386_defconfig @@ -50,7 +50,6 @@ CONFIG_JUMP_LABEL=y CONFIG_MODULES=y CONFIG_MODULE_UNLOAD=y CONFIG_MODULE_FORCE_UNLOAD=y -# CONFIG_UNUSED_SYMBOLS is not set CONFIG_BINFMT_MISC=y CONFIG_NET=y CONFIG_PACKET=y diff --git a/arch/x86/configs/x86_64_defconfig b/arch/x86/configs/x86_64_defconfig index 9936528e1939..b60bd2d86034 100644 --- a/arch/x86/configs/x86_64_defconfig +++ b/arch/x86/configs/x86_64_defconfig @@ -48,7 +48,6 @@ CONFIG_JUMP_LABEL=y CONFIG_MODULES=y CONFIG_MODULE_UNLOAD=y CONFIG_MODULE_FORCE_UNLOAD=y -# CONFIG_UNUSED_SYMBOLS is not set CONFIG_BINFMT_MISC=y CONFIG_NET=y CONFIG_PACKET=y diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c index 1c3a1962cade..04c5a44b9682 100644 --- a/arch/x86/tools/relocs.c +++ b/arch/x86/tools/relocs.c @@ -61,8 +61,8 @@ static const char * const sym_regex_kernel[S_NSYMTYPES] = { "(__iommu_table|__apicdrivers|__smp_locks)(|_end)|" "__(start|end)_pci_.*|" "__(start|end)_builtin_fw|" - "__(start|stop)___ksymtab(|_gpl|_unused|_unused_gpl|_gpl_future)|" - "__(start|stop)___kcrctab(|_gpl|_unused|_unused_gpl|_gpl_future)|" + "__(start|stop)___ksymtab(|_gpl)|" + "__(start|stop)___kcrctab(|_gpl)|" "__(start|stop)___param|" "__(start|stop)___modver|" "__(start|stop)___bug_table|" diff --git a/drivers/gpu/drm/drm_crtc_helper_internal.h b/drivers/gpu/drm/drm_crtc_helper_internal.h index 25ce42e79995..61e09f8a8d0f 100644 --- a/drivers/gpu/drm/drm_crtc_helper_internal.h +++ b/drivers/gpu/drm/drm_crtc_helper_internal.h @@ -32,16 +32,6 @@ #include <drm/drm_encoder.h> #include <drm/drm_modes.h> -/* drm_fb_helper.c */ -#ifdef CONFIG_DRM_FBDEV_EMULATION -int drm_fb_helper_modinit(void); -#else -static inline int drm_fb_helper_modinit(void) -{ - return 0; -} -#endif - /* drm_dp_aux_dev.c */ #ifdef CONFIG_DRM_DP_AUX_CHARDEV int drm_dp_aux_dev_init(void); diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index a44c3a438059..b9a616737c0e 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -2514,24 +2514,3 @@ void drm_fbdev_generic_setup(struct drm_device *dev, drm_client_register(&fb_helper->client); } EXPORT_SYMBOL(drm_fbdev_generic_setup); - -/* The Kconfig DRM_KMS_HELPER selects FRAMEBUFFER_CONSOLE (if !EXPERT) - * but the module doesn't depend on any fb console symbols. At least - * attempt to load fbcon to avoid leaving the system without a usable console. - */ -int __init drm_fb_helper_modinit(void) -{ -#if defined(CONFIG_FRAMEBUFFER_CONSOLE_MODULE) && !defined(CONFIG_EXPERT) - const char name[] = "fbcon"; - struct module *fbcon; - - mutex_lock(&module_mutex); - fbcon = find_module(name); - mutex_unlock(&module_mutex); - - if (!fbcon) - request_module_nowait(name); -#endif - return 0; -} -EXPORT_SYMBOL(drm_fb_helper_modinit); diff --git a/drivers/gpu/drm/drm_kms_helper_common.c b/drivers/gpu/drm/drm_kms_helper_common.c index 221a8528c993..f933da1656eb 100644 --- a/drivers/gpu/drm/drm_kms_helper_common.c +++ b/drivers/gpu/drm/drm_kms_helper_common.c @@ -64,19 +64,18 @@ MODULE_PARM_DESC(edid_firmware, static int __init drm_kms_helper_init(void) { - int ret; - - /* Call init functions from specific kms helpers here */ - ret = drm_fb_helper_modinit(); - if (ret < 0) - goto out; - - ret = drm_dp_aux_dev_init(); - if (ret < 0) - goto out; - -out: - return ret; + /* + * The Kconfig DRM_KMS_HELPER selects FRAMEBUFFER_CONSOLE (if !EXPERT) + * but the module doesn't depend on any fb console symbols. At least + * attempt to load fbcon to avoid leaving the system without a usable + * console. + */ + if (IS_ENABLED(CONFIG_DRM_FBDEV_EMULATION) && + IS_MODULE(CONFIG_FRAMEBUFFER_CONSOLE) && + !IS_ENABLED(CONFIG_EXPERT)) + request_module_nowait("fbcon"); + + return drm_dp_aux_dev_init(); } static void __exit drm_kms_helper_exit(void) diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index d4bddfe75e4a..c54adce8f6f6 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -497,27 +497,6 @@ __stop___ksymtab_gpl = .; \ } \ \ - /* Kernel symbol table: Normal unused symbols */ \ - __ksymtab_unused : AT(ADDR(__ksymtab_unused) - LOAD_OFFSET) { \ - __start___ksymtab_unused = .; \ - KEEP(*(SORT(___ksymtab_unused+*))) \ - __stop___ksymtab_unused = .; \ - } \ - \ - /* Kernel symbol table: GPL-only unused symbols */ \ - __ksymtab_unused_gpl : AT(ADDR(__ksymtab_unused_gpl) - LOAD_OFFSET) { \ - __start___ksymtab_unused_gpl = .; \ - KEEP(*(SORT(___ksymtab_unused_gpl+*))) \ - __stop___ksymtab_unused_gpl = .; \ - } \ - \ - /* Kernel symbol table: GPL-future-only symbols */ \ - __ksymtab_gpl_future : AT(ADDR(__ksymtab_gpl_future) - LOAD_OFFSET) { \ - __start___ksymtab_gpl_future = .; \ - KEEP(*(SORT(___ksymtab_gpl_future+*))) \ - __stop___ksymtab_gpl_future = .; \ - } \ - \ /* Kernel symbol table: Normal symbols */ \ __kcrctab : AT(ADDR(__kcrctab) - LOAD_OFFSET) { \ __start___kcrctab = .; \ @@ -532,27 +511,6 @@ __stop___kcrctab_gpl = .; \ } \ \ - /* Kernel symbol table: Normal unused symbols */ \ - __kcrctab_unused : AT(ADDR(__kcrctab_unused) - LOAD_OFFSET) { \ - __start___kcrctab_unused = .; \ - KEEP(*(SORT(___kcrctab_unused+*))) \ - __stop___kcrctab_unused = .; \ - } \ - \ - /* Kernel symbol table: GPL-only unused symbols */ \ - __kcrctab_unused_gpl : AT(ADDR(__kcrctab_unused_gpl) - LOAD_OFFSET) { \ - __start___kcrctab_unused_gpl = .; \ - KEEP(*(SORT(___kcrctab_unused_gpl+*))) \ - __stop___kcrctab_unused_gpl = .; \ - } \ - \ - /* Kernel symbol table: GPL-future-only symbols */ \ - __kcrctab_gpl_future : AT(ADDR(__kcrctab_gpl_future) - LOAD_OFFSET) { \ - __start___kcrctab_gpl_future = .; \ - KEEP(*(SORT(___kcrctab_gpl_future+*))) \ - __stop___kcrctab_gpl_future = .; \ - } \ - \ /* Kernel symbol table: strings */ \ __ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \ *(__ksymtab_strings) \ diff --git a/include/linux/export.h b/include/linux/export.h index fceb5e855717..6271a5d9c988 100644 --- a/include/linux/export.h +++ b/include/linux/export.h @@ -157,18 +157,9 @@ struct kernel_symbol { #define EXPORT_SYMBOL(sym) _EXPORT_SYMBOL(sym, "") #define EXPORT_SYMBOL_GPL(sym) _EXPORT_SYMBOL(sym, "_gpl") -#define EXPORT_SYMBOL_GPL_FUTURE(sym) _EXPORT_SYMBOL(sym, "_gpl_future") #define EXPORT_SYMBOL_NS(sym, ns) __EXPORT_SYMBOL(sym, "", #ns) #define EXPORT_SYMBOL_NS_GPL(sym, ns) __EXPORT_SYMBOL(sym, "_gpl", #ns) -#ifdef CONFIG_UNUSED_SYMBOLS -#define EXPORT_UNUSED_SYMBOL(sym) _EXPORT_SYMBOL(sym, "_unused") -#define EXPORT_UNUSED_SYMBOL_GPL(sym) _EXPORT_SYMBOL(sym, "_unused_gpl") -#else -#define EXPORT_UNUSED_SYMBOL(sym) -#define EXPORT_UNUSED_SYMBOL_GPL(sym) -#endif - #endif /* !__ASSEMBLY__ */ #endif /* _LINUX_EXPORT_H */ diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h index 481273f0c72d..465060acc981 100644 --- a/include/linux/kallsyms.h +++ b/include/linux/kallsyms.h @@ -71,15 +71,14 @@ static inline void *dereference_symbol_descriptor(void *ptr) return ptr; } -#ifdef CONFIG_KALLSYMS -/* Lookup the address for a symbol. Returns 0 if not found. */ -unsigned long kallsyms_lookup_name(const char *name); - -/* Call a function on each kallsyms symbol in the core kernel */ int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *, unsigned long), void *data); +#ifdef CONFIG_KALLSYMS +/* Lookup the address for a symbol. Returns 0 if not found. */ +unsigned long kallsyms_lookup_name(const char *name); + extern int kallsyms_lookup_size_offset(unsigned long addr, unsigned long *symbolsize, unsigned long *offset); @@ -108,14 +107,6 @@ static inline unsigned long kallsyms_lookup_name(const char *name) return 0; } -static inline int kallsyms_on_each_symbol(int (*fn)(void *, const char *, - struct module *, - unsigned long), - void *data) -{ - return 0; -} - static inline int kallsyms_lookup_size_offset(unsigned long addr, unsigned long *symbolsize, unsigned long *offset) diff --git a/include/linux/module.h b/include/linux/module.h index 7a0bcb5b1ffc..59f094fa6f74 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -392,18 +392,6 @@ struct module { const s32 *gpl_crcs; bool using_gplonly_symbols; -#ifdef CONFIG_UNUSED_SYMBOLS - /* unused exported symbols. */ - const struct kernel_symbol *unused_syms; - const s32 *unused_crcs; - unsigned int num_unused_syms; - - /* GPL-only, unused exported symbols. */ - unsigned int num_unused_gpl_syms; - const struct kernel_symbol *unused_gpl_syms; - const s32 *unused_gpl_crcs; -#endif - #ifdef CONFIG_MODULE_SIG /* Signature was verified. */ bool sig_ok; @@ -411,11 +399,6 @@ struct module { bool async_probe_requested; - /* symbols that will be GPL-only in the near future. */ - const struct kernel_symbol *gpl_future_syms; - const s32 *gpl_future_crcs; - unsigned int num_gpl_future_syms; - /* Exception table */ unsigned int num_exentries; struct exception_table_entry *extable; @@ -550,8 +533,6 @@ static inline unsigned long kallsyms_symbol_value(const Elf_Sym *sym) } #endif -extern struct mutex module_mutex; - /* FIXME: It'd be nice to isolate modules during init, too, so they aren't used before they (may) fail. But presently too much code (IDE & SCSI) require entry into the module during init.*/ @@ -586,20 +567,9 @@ static inline bool within_module(unsigned long addr, const struct module *mod) return within_module_init(addr, mod) || within_module_core(addr, mod); } -/* Search for module by name: must hold module_mutex. */ +/* Search for module by name: must be in a RCU-sched critical section. */ struct module *find_module(const char *name); -struct symsearch { - const struct kernel_symbol *start, *stop; - const s32 *crcs; - enum mod_license { - NOT_GPL_ONLY, - GPL_ONLY, - WILL_BE_GPL_ONLY, - } license; - bool unused; -}; - /* Returns 0 and fills in value, defined and namebuf, or -ERANGE if symnum out of range. */ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, @@ -608,10 +578,6 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, /* Look for this name: can be of form module:name. */ unsigned long module_kallsyms_lookup_name(const char *name); -int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, - struct module *, unsigned long), - void *data); - extern void __noreturn __module_put_and_exit(struct module *mod, long code); #define module_put_and_exit(code) __module_put_and_exit(THIS_MODULE, code) @@ -795,14 +761,6 @@ static inline unsigned long module_kallsyms_lookup_name(const char *name) return 0; } -static inline int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, - struct module *, - unsigned long), - void *data) -{ - return 0; -} - static inline int register_module_notifier(struct notifier_block *nb) { /* no events will happen anyway, so this can always succeed */ @@ -891,4 +849,8 @@ static inline bool module_sig_ok(struct module *module) } #endif /* CONFIG_MODULE_SIG */ +int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, + struct module *, unsigned long), + void *data); + #endif /* _LINUX_MODULE_H */ diff --git a/init/Kconfig b/init/Kconfig index 57f859ea79b9..8a2c0e41f1bb 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -2272,25 +2272,8 @@ config MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS If unsure, say N. -config UNUSED_SYMBOLS - bool "Enable unused/obsolete exported symbols" - default y if X86 - help - Unused but exported symbols make the kernel needlessly bigger. For - that reason most of these unused exports will soon be removed. This - option is provided temporarily to provide a transition period in case - some external kernel module needs one of these symbols anyway. If you - encounter such a case in your module, consider if you are actually - using the right API. (rationale: since nobody in the kernel is using - this in a module, there is a pretty good chance it's actually the - wrong interface to use). If you really need the symbol, please send a - mail to the linux kernel mailing list mentioning the symbol and why - you really need it, and what the merge plan to the mainline kernel for - your module is. - config TRIM_UNUSED_KSYMS bool "Trim unused exported kernel symbols" - depends on !UNUSED_SYMBOLS help The kernel and some modules make many symbols available for other modules to use via EXPORT_SYMBOL() and variants. Depending diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index fe9de067771c..8043a90aa50e 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -177,6 +177,11 @@ unsigned long kallsyms_lookup_name(const char *name) return module_kallsyms_lookup_name(name); } +#ifdef CONFIG_LIVEPATCH +/* + * Iterate over all symbols in vmlinux. For symbols from modules use + * module_kallsyms_on_each_symbol instead. + */ int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *, unsigned long), void *data) @@ -192,8 +197,9 @@ int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *, if (ret != 0) return ret; } - return module_kallsyms_on_each_symbol(fn, data); + return 0; } +#endif /* CONFIG_LIVEPATCH */ static unsigned long get_symbol_pos(unsigned long addr, unsigned long *symbolsize, diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index f76fdb925532..335d988bd811 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -19,6 +19,7 @@ #include <linux/moduleloader.h> #include <linux/completion.h> #include <linux/memory.h> +#include <linux/rcupdate.h> #include <asm/cacheflush.h> #include "core.h" #include "patch.h" @@ -57,7 +58,7 @@ static void klp_find_object_module(struct klp_object *obj) if (!klp_is_module(obj)) return; - mutex_lock(&module_mutex); + rcu_read_lock_sched(); /* * We do not want to block removal of patched modules and therefore * we do not take a reference here. The patches are removed by @@ -74,7 +75,7 @@ static void klp_find_object_module(struct klp_object *obj) if (mod && mod->klp_alive) obj->mod = mod; - mutex_unlock(&module_mutex); + rcu_read_unlock_sched(); } static bool klp_initialized(void) @@ -163,12 +164,10 @@ static int klp_find_object_symbol(const char *objname, const char *name, .pos = sympos, }; - mutex_lock(&module_mutex); if (objname) module_kallsyms_on_each_symbol(klp_find_callback, &args); else kallsyms_on_each_symbol(klp_find_callback, &args); - mutex_unlock(&module_mutex); /* * Ensure an address was found. If sympos is 0, ensure symbol is unique; diff --git a/kernel/module.c b/kernel/module.c index 4bf30e4b3eaa..30479355ab85 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -87,8 +87,7 @@ * 3) module_addr_min/module_addr_max. * (delete and add uses RCU list operations). */ -DEFINE_MUTEX(module_mutex); -EXPORT_SYMBOL_GPL(module_mutex); +static DEFINE_MUTEX(module_mutex); static LIST_HEAD(modules); /* Work queue for freeing init sections in success case */ @@ -256,11 +255,6 @@ static void mod_update_bounds(struct module *mod) struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */ #endif /* CONFIG_KGDB_KDB */ -static void module_assert_mutex(void) -{ - lockdep_assert_held(&module_mutex); -} - static void module_assert_mutex_or_preempt(void) { #ifdef CONFIG_LOCKDEP @@ -414,19 +408,8 @@ extern const struct kernel_symbol __start___ksymtab[]; extern const struct kernel_symbol __stop___ksymtab[]; extern const struct kernel_symbol __start___ksymtab_gpl[]; extern const struct kernel_symbol __stop___ksymtab_gpl[]; -extern const struct kernel_symbol __start___ksymtab_gpl_future[]; -extern const struct kernel_symbol __stop___ksymtab_gpl_future[]; extern const s32 __start___kcrctab[]; extern const s32 __start___kcrctab_gpl[]; -extern const s32 __start___kcrctab_gpl_future[]; -#ifdef CONFIG_UNUSED_SYMBOLS -extern const struct kernel_symbol __start___ksymtab_unused[]; -extern const struct kernel_symbol __stop___ksymtab_unused[]; -extern const struct kernel_symbol __start___ksymtab_unused_gpl[]; -extern const struct kernel_symbol __stop___ksymtab_unused_gpl[]; -extern const s32 __start___kcrctab_unused[]; -extern const s32 __start___kcrctab_unused_gpl[]; -#endif #ifndef CONFIG_MODVERSIONS #define symversion(base, idx) NULL @@ -434,87 +417,14 @@ extern const s32 __start___kcrctab_unused_gpl[]; #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL) #endif -static bool each_symbol_in_section(const struct symsearch *arr, - unsigned int arrsize, - struct module *owner, - bool (*fn)(const struct symsearch *syms, - struct module *owner, - void *data), - void *data) -{ - unsigned int j; - - for (j = 0; j < arrsize; j++) { - if (fn(&arr[j], owner, data)) - return true; - } - - return false; -} - -/* Returns true as soon as fn returns true, otherwise false. */ -static bool each_symbol_section(bool (*fn)(const struct symsearch *arr, - struct module *owner, - void *data), - void *data) -{ - struct module *mod; - static const struct symsearch arr[] = { - { __start___ksymtab, __stop___ksymtab, __start___kcrctab, - NOT_GPL_ONLY, false }, - { __start___ksymtab_gpl, __stop___ksymtab_gpl, - __start___kcrctab_gpl, - GPL_ONLY, false }, - { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future, - __start___kcrctab_gpl_future, - WILL_BE_GPL_ONLY, false }, -#ifdef CONFIG_UNUSED_SYMBOLS - { __start___ksymtab_unused, __stop___ksymtab_unused, - __start___kcrctab_unused, - NOT_GPL_ONLY, true }, - { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl, - __start___kcrctab_unused_gpl, - GPL_ONLY, true }, -#endif - }; - - module_assert_mutex_or_preempt(); - - if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data)) - return true; - - list_for_each_entry_rcu(mod, &modules, list, - lockdep_is_held(&module_mutex)) { - struct symsearch arr[] = { - { mod->syms, mod->syms + mod->num_syms, mod->crcs, - NOT_GPL_ONLY, false }, - { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms, - mod->gpl_crcs, - GPL_ONLY, false }, - { mod->gpl_future_syms, - mod->gpl_future_syms + mod->num_gpl_future_syms, - mod->gpl_future_crcs, - WILL_BE_GPL_ONLY, false }, -#ifdef CONFIG_UNUSED_SYMBOLS - { mod->unused_syms, - mod->unused_syms + mod->num_unused_syms, - mod->unused_crcs, - NOT_GPL_ONLY, true }, - { mod->unused_gpl_syms, - mod->unused_gpl_syms + mod->num_unused_gpl_syms, - mod->unused_gpl_crcs, - GPL_ONLY, true }, -#endif - }; - - if (mod->state == MODULE_STATE_UNFORMED) - continue; - - if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data)) - return true; - } - return false; -} +struct symsearch { + const struct kernel_symbol *start, *stop; + const s32 *crcs; + enum mod_license { + NOT_GPL_ONLY, + GPL_ONLY, + } license; +}; struct find_symbol_arg { /* Input */ @@ -535,28 +445,8 @@ static bool check_exported_symbol(const struct symsearch *syms, { struct find_symbol_arg *fsa = data; - if (!fsa->gplok) { - if (syms->license == GPL_ONLY) - return false; - if (syms->license == WILL_BE_GPL_ONLY && fsa->warn) { - pr_warn("Symbol %s is being used by a non-GPL module, " - "which will not be allowed in the future\n", - fsa->name); - } - } - -#ifdef CONFIG_UNUSED_SYMBOLS - if (syms->unused && fsa->warn) { - pr_warn("Symbol %s is marked as UNUSED, however this module is " - "using it.\n", fsa->name); - pr_warn("This symbol will go away in the future.\n"); - pr_warn("Please evaluate if this is the right api to use and " - "if it really is, submit a report to the linux kernel " - "mailing list together with submitting your code for " - "inclusion.\n"); - } -#endif - + if (!fsa->gplok && syms->license == GPL_ONLY) + return false; fsa->owner = owner; fsa->crc = symversion(syms->crcs, symnum); fsa->sym = &syms->start[symnum]; @@ -619,31 +509,44 @@ static bool find_exported_symbol_in_section(const struct symsearch *syms, * Find an exported symbol and return it, along with, (optional) crc and * (optional) module which owns it. Needs preempt disabled or module_mutex. */ -static const struct kernel_symbol *find_symbol(const char *name, - struct module **owner, - const s32 **crc, - enum mod_license *license, - bool gplok, - bool warn) -{ - struct find_symbol_arg fsa; - - fsa.name = name; - fsa.gplok = gplok; - fsa.warn = warn; - - if (each_symbol_section(find_exported_symbol_in_section, &fsa)) { - if (owner) - *owner = fsa.owner; - if (crc) - *crc = fsa.crc; - if (license) - *license = fsa.license; - return fsa.sym; +static bool find_symbol(struct find_symbol_arg *fsa) +{ + static const struct symsearch arr[] = { + { __start___ksymtab, __stop___ksymtab, __start___kcrctab, + NOT_GPL_ONLY }, + { __start___ksymtab_gpl, __stop___ksymtab_gpl, + __start___kcrctab_gpl, + GPL_ONLY }, + }; + struct module *mod; + unsigned int i; + + module_assert_mutex_or_preempt(); + + for (i = 0; i < ARRAY_SIZE(arr); i++) + if (find_exported_symbol_in_section(&arr[i], NULL, fsa)) + return true; + + list_for_each_entry_rcu(mod, &modules, list, + lockdep_is_held(&module_mutex)) { + struct symsearch arr[] = { + { mod->syms, mod->syms + mod->num_syms, mod->crcs, + NOT_GPL_ONLY }, + { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms, + mod->gpl_crcs, + GPL_ONLY }, + }; + + if (mod->state == MODULE_STATE_UNFORMED) + continue; + + for (i = 0; i < ARRAY_SIZE(arr); i++) + if (find_exported_symbol_in_section(&arr[i], mod, fsa)) + return true; } - pr_debug("Failed to find symbol %s\n", name); - return NULL; + pr_debug("Failed to find symbol %s\n", fsa->name); + return false; } /* @@ -669,10 +572,8 @@ static struct module *find_module_all(const char *name, size_t len, struct module *find_module(const char *name) { - module_assert_mutex(); return find_module_all(name, strlen(name), false); } -EXPORT_SYMBOL_GPL(find_module); #ifdef CONFIG_SMP @@ -1107,12 +1008,15 @@ static inline void print_unload_info(struct seq_file *m, struct module *mod) void __symbol_put(const char *symbol) { - struct module *owner; + struct find_symbol_arg fsa = { + .name = symbol, + .gplok = true, + }; preempt_disable(); - if (!find_symbol(symbol, &owner, NULL, NULL, true, false)) + if (!find_symbol(&fsa)) BUG(); - module_put(owner); + module_put(fsa.owner); preempt_enable(); } EXPORT_SYMBOL(__symbol_put); @@ -1381,19 +1285,22 @@ bad_version: static inline int check_modstruct_version(const struct load_info *info, struct module *mod) { - const s32 *crc; + struct find_symbol_arg fsa = { + .name = "module_layout", + .gplok = true, + }; /* * Since this should be found in kernel (which can't be removed), no * locking is necessary -- use preempt_disable() to placate lockdep. */ preempt_disable(); - if (!find_symbol("module_layout", NULL, &crc, NULL, true, false)) { + if (!find_symbol(&fsa)) { preempt_enable(); BUG(); } preempt_enable(); - return check_version(info, "module_layout", mod, crc); + return check_version(info, "module_layout", mod, fsa.crc); } /* First part is kernel version, which we ignore if module has crcs. */ @@ -1487,10 +1394,11 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod, const char *name, char ownername[]) { - struct module *owner; - const struct kernel_symbol *sym; - const s32 *crc; - enum mod_license license; + struct find_symbol_arg fsa = { + .name = name, + .gplok = !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), + .warn = true, + }; int err; /* @@ -1500,42 +1408,40 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod, */ sched_annotate_sleep(); mutex_lock(&module_mutex); - sym = find_symbol(name, &owner, &crc, &license, - !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true); - if (!sym) + if (!find_symbol(&fsa)) goto unlock; - if (license == GPL_ONLY) + if (fsa.license == GPL_ONLY) mod->using_gplonly_symbols = true; - if (!inherit_taint(mod, owner)) { - sym = NULL; + if (!inherit_taint(mod, fsa.owner)) { + fsa.sym = NULL; goto getname; } - if (!check_version(info, name, mod, crc)) { - sym = ERR_PTR(-EINVAL); + if (!check_version(info, name, mod, fsa.crc)) { + fsa.sym = ERR_PTR(-EINVAL); goto getname; } - err = verify_namespace_is_imported(info, sym, mod); + err = verify_namespace_is_imported(info, fsa.sym, mod); if (err) { - sym = ERR_PTR(err); + fsa.sym = ERR_PTR(err); goto getname; } - err = ref_module(mod, owner); + err = ref_module(mod, fsa.owner); if (err) { - sym = ERR_PTR(err); + fsa.sym = ERR_PTR(err); goto getname; } getname: /* We must make copy under the lock if we failed to get ref. */ - strncpy(ownername, module_name(owner), MODULE_NAME_LEN); + strncpy(ownername, module_name(fsa.owner), MODULE_NAME_LEN); unlock: mutex_unlock(&module_mutex); - return sym; + return fsa.sym; } static const struct kernel_symbol * @@ -2296,16 +2202,19 @@ static void free_module(struct module *mod) void *__symbol_get(const char *symbol) { - struct module *owner; - const struct kernel_symbol *sym; + struct find_symbol_arg fsa = { + .name = symbol, + .gplok = true, + .warn = true, + }; preempt_disable(); - sym = find_symbol(symbol, &owner, NULL, NULL, true, true); - if (sym && strong_try_module_get(owner)) - sym = NULL; + if (!find_symbol(&fsa) || strong_try_module_get(fsa.owner)) { + preempt_enable(); + return NULL; + } preempt_enable(); - - return sym ? (void *)kernel_symbol_value(sym) : NULL; + return (void *)kernel_symbol_value(fsa.sym); } EXPORT_SYMBOL_GPL(__symbol_get); @@ -2318,7 +2227,6 @@ EXPORT_SYMBOL_GPL(__symbol_get); static int verify_exported_symbols(struct module *mod) { unsigned int i; - struct module *owner; const struct kernel_symbol *s; struct { const struct kernel_symbol *sym; @@ -2326,21 +2234,19 @@ static int verify_exported_symbols(struct module *mod) } arr[] = { { mod->syms, mod->num_syms }, { mod->gpl_syms, mod->num_gpl_syms }, - { mod->gpl_future_syms, mod->num_gpl_future_syms }, -#ifdef CONFIG_UNUSED_SYMBOLS - { mod->unused_syms, mod->num_unused_syms }, - { mod->unused_gpl_syms, mod->num_unused_gpl_syms }, -#endif }; for (i = 0; i < ARRAY_SIZE(arr); i++) { for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) { - if (find_symbol(kernel_symbol_name(s), &owner, NULL, - NULL, true, false)) { + struct find_symbol_arg fsa = { + .name = kernel_symbol_name(s), + .gplok = true, + }; + if (find_symbol(&fsa)) { pr_err("%s: exports duplicate symbol %s" " (owned by %s)\n", mod->name, kernel_symbol_name(s), - module_name(owner)); + module_name(fsa.owner)); return -ENOEXEC; } } @@ -2348,6 +2254,21 @@ static int verify_exported_symbols(struct module *mod) return 0; } +static bool ignore_undef_symbol(Elf_Half emachine, const char *name) +{ + /* + * On x86, PIC code and Clang non-PIC code may have call foo@PLT. GNU as + * before 2.37 produces an unreferenced _GLOBAL_OFFSET_TABLE_ on x86-64. + * i386 has a similar problem but may not deserve a fix. + * + * If we ever have to ignore many symbols, consider refactoring the code to + * only warn if referenced by a relocation. + */ + if (emachine == EM_386 || emachine == EM_X86_64) + return !strcmp(name, "_GLOBAL_OFFSET_TABLE_"); + return false; +} + /* Change all symbols so that st_value encodes the pointer directly. */ static int simplify_symbols(struct module *mod, const struct load_info *info) { @@ -2395,8 +2316,10 @@ static int simplify_symbols(struct module *mod, const struct load_info *info) break; } - /* Ok if weak. */ - if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK) + /* Ok if weak or ignored. */ + if (!ksym && + (ELF_ST_BIND(sym[i].st_info) == STB_WEAK || + ignore_undef_symbol(info->hdr->e_machine, name))) break; ret = PTR_ERR(ksym) ?: -ENOENT; @@ -2964,7 +2887,7 @@ static int module_sig_check(struct load_info *info, int flags) } if (is_module_sig_enforced()) { - pr_notice("%s: loading of %s is rejected\n", info->name, reason); + pr_notice("Loading of %s is rejected\n", reason); return -EKEYREJECTED; } @@ -2977,9 +2900,33 @@ static int module_sig_check(struct load_info *info, int flags) } #endif /* !CONFIG_MODULE_SIG */ -/* Sanity checks against invalid binaries, wrong arch, weird elf version. */ -static int elf_header_check(struct load_info *info) +static int validate_section_offset(struct load_info *info, Elf_Shdr *shdr) +{ + unsigned long secend; + + /* + * Check for both overflow and offset/size being + * too large. + */ + secend = shdr->sh_offset + shdr->sh_size; + if (secend < shdr->sh_offset || secend > info->len) + return -ENOEXEC; + + return 0; +} + +/* + * Sanity checks against invalid binaries, wrong arch, weird elf version. + * + * Also do basic validity checks against section offsets and sizes, the + * section name string table, and the indices used for it (sh_name). + */ +static int elf_validity_check(struct load_info *info) { + unsigned int i; + Elf_Shdr *shdr, *strhdr; + int err; + if (info->len < sizeof(*(info->hdr))) return -ENOEXEC; @@ -2989,11 +2936,78 @@ static int elf_header_check(struct load_info *info) || info->hdr->e_shentsize != sizeof(Elf_Shdr)) return -ENOEXEC; + /* + * e_shnum is 16 bits, and sizeof(Elf_Shdr) is + * known and small. So e_shnum * sizeof(Elf_Shdr) + * will not overflow unsigned long on any platform. + */ if (info->hdr->e_shoff >= info->len || (info->hdr->e_shnum * sizeof(Elf_Shdr) > info->len - info->hdr->e_shoff)) return -ENOEXEC; + info->sechdrs = (void *)info->hdr + info->hdr->e_shoff; + + /* + * Verify if the section name table index is valid. + */ + if (info->hdr->e_shstrndx == SHN_UNDEF + || info->hdr->e_shstrndx >= info->hdr->e_shnum) + return -ENOEXEC; + + strhdr = &info->sechdrs[info->hdr->e_shstrndx]; + err = validate_section_offset(info, strhdr); + if (err < 0) + return err; + + /* + * The section name table must be NUL-terminated, as required + * by the spec. This makes strcmp and pr_* calls that access + * strings in the section safe. + */ + info->secstrings = (void *)info->hdr + strhdr->sh_offset; + if (info->secstrings[strhdr->sh_size - 1] != '\0') + return -ENOEXEC; + + /* + * The code assumes that section 0 has a length of zero and + * an addr of zero, so check for it. + */ + if (info->sechdrs[0].sh_type != SHT_NULL + || info->sechdrs[0].sh_size != 0 + || info->sechdrs[0].sh_addr != 0) + return -ENOEXEC; + + for (i = 1; i < info->hdr->e_shnum; i++) { + shdr = &info->sechdrs[i]; + switch (shdr->sh_type) { + case SHT_NULL: + case SHT_NOBITS: + continue; + case SHT_SYMTAB: + if (shdr->sh_link == SHN_UNDEF + || shdr->sh_link >= info->hdr->e_shnum) + return -ENOEXEC; + fallthrough; + default: + err = validate_section_offset(info, shdr); + if (err < 0) { + pr_err("Invalid ELF section in module (section %u type %u)\n", + i, shdr->sh_type); + return err; + } + + if (shdr->sh_flags & SHF_ALLOC) { + if (shdr->sh_name >= strhdr->sh_size) { + pr_err("Invalid ELF section name in module (section %u type %u)\n", + i, shdr->sh_type); + return -ENOEXEC; + } + } + break; + } + } + return 0; } @@ -3095,11 +3109,6 @@ static int rewrite_section_headers(struct load_info *info, int flags) for (i = 1; i < info->hdr->e_shnum; i++) { Elf_Shdr *shdr = &info->sechdrs[i]; - if (shdr->sh_type != SHT_NOBITS - && info->len < shdr->sh_offset + shdr->sh_size) { - pr_err("Module len %lu truncated\n", info->len); - return -ENOEXEC; - } /* * Mark all sections sh_addr with their address in the @@ -3133,11 +3142,6 @@ static int setup_load_info(struct load_info *info, int flags) { unsigned int i; - /* Set up the convenience variables */ - info->sechdrs = (void *)info->hdr + info->hdr->e_shoff; - info->secstrings = (void *)info->hdr - + info->sechdrs[info->hdr->e_shstrndx].sh_offset; - /* Try to find a name early so we can log errors with a module name */ info->index.info = find_sec(info, ".modinfo"); if (info->index.info) @@ -3241,22 +3245,7 @@ static int find_module_sections(struct module *mod, struct load_info *info) sizeof(*mod->gpl_syms), &mod->num_gpl_syms); mod->gpl_crcs = section_addr(info, "__kcrctab_gpl"); - mod->gpl_future_syms = section_objs(info, - "__ksymtab_gpl_future", - sizeof(*mod->gpl_future_syms), - &mod->num_gpl_future_syms); - mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future"); - -#ifdef CONFIG_UNUSED_SYMBOLS - mod->unused_syms = section_objs(info, "__ksymtab_unused", - sizeof(*mod->unused_syms), - &mod->num_unused_syms); - mod->unused_crcs = section_addr(info, "__kcrctab_unused"); - mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl", - sizeof(*mod->unused_gpl_syms), - &mod->num_unused_gpl_syms); - mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl"); -#endif + #ifdef CONFIG_CONSTRUCTORS mod->ctors = section_objs(info, ".ctors", sizeof(*mod->ctors), &mod->num_ctors); @@ -3437,14 +3426,8 @@ static int check_module_license_and_versions(struct module *mod) pr_warn("%s: module license taints kernel.\n", mod->name); #ifdef CONFIG_MODVERSIONS - if ((mod->num_syms && !mod->crcs) - || (mod->num_gpl_syms && !mod->gpl_crcs) - || (mod->num_gpl_future_syms && !mod->gpl_future_crcs) -#ifdef CONFIG_UNUSED_SYMBOLS - || (mod->num_unused_syms && !mod->unused_crcs) - || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs) -#endif - ) { + if ((mod->num_syms && !mod->crcs) || + (mod->num_gpl_syms && !mod->gpl_crcs)) { return try_to_force_load(mod, "no versions for exported symbols"); } @@ -3894,26 +3877,50 @@ static int load_module(struct load_info *info, const char __user *uargs, long err = 0; char *after_dashes; - err = elf_header_check(info); + /* + * Do the signature check (if any) first. All that + * the signature check needs is info->len, it does + * not need any of the section info. That can be + * set up later. This will minimize the chances + * of a corrupt module causing problems before + * we even get to the signature check. + * + * The check will also adjust info->len by stripping + * off the sig length at the end of the module, making + * checks against info->len more correct. + */ + err = module_sig_check(info, flags); + if (err) + goto free_copy; + + /* + * Do basic sanity checks against the ELF header and + * sections. + */ + err = elf_validity_check(info); if (err) { - pr_err("Module has invalid ELF header\n"); + pr_err("Module has invalid ELF structures\n"); goto free_copy; } + /* + * Everything checks out, so set up the section info + * in the info structure. + */ err = setup_load_info(info, flags); if (err) goto free_copy; + /* + * Now that we know we have the correct module name, check + * if it's blacklisted. + */ if (blacklisted(info->name)) { err = -EPERM; pr_err("Module %s is blacklisted\n", info->name); goto free_copy; } - err = module_sig_check(info, flags); - if (err) - goto free_copy; - err = rewrite_section_headers(info, flags); if (err) goto free_copy; @@ -4374,16 +4381,16 @@ unsigned long module_kallsyms_lookup_name(const char *name) return ret; } +#ifdef CONFIG_LIVEPATCH int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *, unsigned long), void *data) { struct module *mod; unsigned int i; - int ret; - - module_assert_mutex(); + int ret = 0; + mutex_lock(&module_mutex); list_for_each_entry(mod, &modules, list) { /* We hold module_mutex: no need for rcu_dereference_sched */ struct mod_kallsyms *kallsyms = mod->kallsyms; @@ -4399,11 +4406,13 @@ int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, ret = fn(data, kallsyms_symbol_name(kallsyms, i), mod, kallsyms_symbol_value(sym)); if (ret != 0) - return ret; + break; } } - return 0; + mutex_unlock(&module_mutex); + return ret; } +#endif /* CONFIG_LIVEPATCH */ #endif /* CONFIG_KALLSYMS */ /* Maximum number of characters written by module_flags() */ diff --git a/kernel/module_signature.c b/kernel/module_signature.c index 4224a1086b7d..00132d12487c 100644 --- a/kernel/module_signature.c +++ b/kernel/module_signature.c @@ -25,7 +25,7 @@ int mod_check_sig(const struct module_signature *ms, size_t file_len, return -EBADMSG; if (ms->id_type != PKEY_ID_PKCS7) { - pr_err("%s: Module is not signed with expected PKCS#7 message\n", + pr_err("%s: not signed with expected PKCS#7 message\n", name); return -ENOPKG; } diff --git a/kernel/module_signing.c b/kernel/module_signing.c index 9d9fc678c91d..8723ae70ea1f 100644 --- a/kernel/module_signing.c +++ b/kernel/module_signing.c @@ -30,7 +30,7 @@ int mod_verify_sig(const void *mod, struct load_info *info) memcpy(&ms, mod + (modlen - sizeof(ms)), sizeof(ms)); - ret = mod_check_sig(&ms, modlen, info->name); + ret = mod_check_sig(&ms, modlen, "module"); if (ret) return ret; diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 8a1cb0878cbc..6fe770d86dc3 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -124,9 +124,9 @@ static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) if (!p) return true; *p = '\0'; - mutex_lock(&module_mutex); + rcu_read_lock_sched(); ret = !!find_module(tk->symbol); - mutex_unlock(&module_mutex); + rcu_read_unlock_sched(); *p = ':'; return ret; diff --git a/lib/bug.c b/lib/bug.c index 7103440c0ee1..8f9d537bfb2a 100644 --- a/lib/bug.c +++ b/lib/bug.c @@ -91,8 +91,6 @@ void module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, char *secstrings; unsigned int i; - lockdep_assert_held(&module_mutex); - mod->bug_table = NULL; mod->num_bugs = 0; @@ -118,7 +116,6 @@ void module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, void module_bug_cleanup(struct module *mod) { - lockdep_assert_held(&module_mutex); list_del_rcu(&mod->bug_list); } diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 4b2775fd31d9..ca4201753d5e 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -4283,8 +4283,7 @@ sub process { if (defined $realline_next && exists $lines[$realline_next - 1] && !defined $suppress_export{$realline_next} && - ($lines[$realline_next - 1] =~ /EXPORT_SYMBOL.*\((.*)\)/ || - $lines[$realline_next - 1] =~ /EXPORT_UNUSED_SYMBOL.*\((.*)\)/)) { + ($lines[$realline_next - 1] =~ /EXPORT_SYMBOL.*\((.*)\)/)) { # Handle definitions which produce identifiers with # a prefix: # XXX(foo); @@ -4311,8 +4310,7 @@ sub process { } if (!defined $suppress_export{$linenr} && $prevline =~ /^.\s*$/ && - ($line =~ /EXPORT_SYMBOL.*\((.*)\)/ || - $line =~ /EXPORT_UNUSED_SYMBOL.*\((.*)\)/)) { + ($line =~ /EXPORT_SYMBOL.*\((.*)\)/)) { #print "FOO B <$lines[$linenr - 1]>\n"; $suppress_export{$linenr} = 2; } diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index be0642126f53..24725e50c7b4 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -42,8 +42,9 @@ static int allow_missing_ns_imports; static bool error_occurred; enum export { - export_plain, export_unused, export_gpl, - export_unused_gpl, export_gpl_future, export_unknown + export_plain, + export_gpl, + export_unknown }; /* In kernel, this size is defined in linux/module.h; @@ -292,10 +293,7 @@ static const struct { enum export export; } export_list[] = { { .str = "EXPORT_SYMBOL", .export = export_plain }, - { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused }, { .str = "EXPORT_SYMBOL_GPL", .export = export_gpl }, - { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl }, - { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future }, { .str = "(unknown)", .export = export_unknown }, }; @@ -354,14 +352,8 @@ static enum export export_from_secname(struct elf_info *elf, unsigned int sec) if (strstarts(secname, "___ksymtab+")) return export_plain; - else if (strstarts(secname, "___ksymtab_unused+")) - return export_unused; else if (strstarts(secname, "___ksymtab_gpl+")) return export_gpl; - else if (strstarts(secname, "___ksymtab_unused_gpl+")) - return export_unused_gpl; - else if (strstarts(secname, "___ksymtab_gpl_future+")) - return export_gpl_future; else return export_unknown; } @@ -370,14 +362,8 @@ static enum export export_from_sec(struct elf_info *elf, unsigned int sec) { if (sec == elf->export_sec) return export_plain; - else if (sec == elf->export_unused_sec) - return export_unused; else if (sec == elf->export_gpl_sec) return export_gpl; - else if (sec == elf->export_unused_gpl_sec) - return export_unused_gpl; - else if (sec == elf->export_gpl_future_sec) - return export_gpl_future; else return export_unknown; } @@ -581,14 +567,8 @@ static int parse_elf(struct elf_info *info, const char *filename) info->modinfo_len = sechdrs[i].sh_size; } else if (strcmp(secname, "__ksymtab") == 0) info->export_sec = i; - else if (strcmp(secname, "__ksymtab_unused") == 0) - info->export_unused_sec = i; else if (strcmp(secname, "__ksymtab_gpl") == 0) info->export_gpl_sec = i; - else if (strcmp(secname, "__ksymtab_unused_gpl") == 0) - info->export_unused_gpl_sec = i; - else if (strcmp(secname, "__ksymtab_gpl_future") == 0) - info->export_gpl_future_sec = i; if (sechdrs[i].sh_type == SHT_SYMTAB) { unsigned int sh_link_idx; @@ -2146,36 +2126,13 @@ static void check_for_gpl_usage(enum export exp, const char *m, const char *s) error("GPL-incompatible module %s.ko uses GPL-only symbol '%s'\n", m, s); break; - case export_unused_gpl: - error("GPL-incompatible module %s.ko uses GPL-only symbol marked UNUSED '%s'\n", - m, s); - break; - case export_gpl_future: - warn("GPL-incompatible module %s.ko uses future GPL-only symbol '%s'\n", - m, s); - break; case export_plain: - case export_unused: case export_unknown: /* ignore */ break; } } -static void check_for_unused(enum export exp, const char *m, const char *s) -{ - switch (exp) { - case export_unused: - case export_unused_gpl: - warn("module %s.ko uses symbol '%s' marked UNUSED\n", - m, s); - break; - default: - /* ignore */ - break; - } -} - static void check_exports(struct module *mod) { struct symbol *s, *exp; @@ -2206,7 +2163,6 @@ static void check_exports(struct module *mod) if (!mod->gpl_compatible) check_for_gpl_usage(exp->export, basename, exp->name); - check_for_unused(exp->export, basename, exp->name); } } diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index 1f76eea7cfde..c1a895c0d682 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -140,10 +140,7 @@ struct elf_info { Elf_Sym *symtab_start; Elf_Sym *symtab_stop; Elf_Section export_sec; - Elf_Section export_unused_sec; Elf_Section export_gpl_sec; - Elf_Section export_unused_gpl_sec; - Elf_Section export_gpl_future_sec; char *strtab; char *modinfo; unsigned int modinfo_len; diff --git a/scripts/module.lds.S b/scripts/module.lds.S index 18d5b8423635..168cd27e6122 100644 --- a/scripts/module.lds.S +++ b/scripts/module.lds.S @@ -11,14 +11,8 @@ SECTIONS { __ksymtab 0 : { *(SORT(___ksymtab+*)) } __ksymtab_gpl 0 : { *(SORT(___ksymtab_gpl+*)) } - __ksymtab_unused 0 : { *(SORT(___ksymtab_unused+*)) } - __ksymtab_unused_gpl 0 : { *(SORT(___ksymtab_unused_gpl+*)) } - __ksymtab_gpl_future 0 : { *(SORT(___ksymtab_gpl_future+*)) } __kcrctab 0 : { *(SORT(___kcrctab+*)) } __kcrctab_gpl 0 : { *(SORT(___kcrctab_gpl+*)) } - __kcrctab_unused 0 : { *(SORT(___kcrctab_unused+*)) } - __kcrctab_unused_gpl 0 : { *(SORT(___kcrctab_unused_gpl+*)) } - __kcrctab_gpl_future 0 : { *(SORT(___kcrctab_gpl_future+*)) } .init_array 0 : ALIGN(8) { *(SORT(.init_array.*)) *(.init_array) } diff --git a/tools/include/linux/export.h b/tools/include/linux/export.h index d07e586b9ba0..acb6f4daa2f0 100644 --- a/tools/include/linux/export.h +++ b/tools/include/linux/export.h @@ -3,8 +3,5 @@ #define EXPORT_SYMBOL(sym) #define EXPORT_SYMBOL_GPL(sym) -#define EXPORT_SYMBOL_GPL_FUTURE(sym) -#define EXPORT_UNUSED_SYMBOL(sym) -#define EXPORT_UNUSED_SYMBOL_GPL(sym) #endif |