lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Fri, 10 Nov 2017 08:48:27 +0900 From: Sergey Senozhatsky <sergey.senozhatsky@...il.com> To: Tony Luck <tony.luck@...el.com>, Fenghua Yu <fenghua.yu@...el.com>, Helge Deller <deller@....de>, Benjamin Herrenschmidt <benh@...nel.crashing.org>, Paul Mackerras <paulus@...ba.org>, Michael Ellerman <mpe@...erman.id.au>, James Bottomley <jejb@...isc-linux.org> Cc: Andrew Morton <akpm@...ux-foundation.org>, Jessica Yu <jeyu@...nel.org>, Petr Mladek <pmladek@...e.com>, Steven Rostedt <rostedt@...dmis.org>, linux-ia64@...r.kernel.org, linux-parisc@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org, linux-kernel@...r.kernel.org, Sergey Senozhatsky <sergey.senozhatsky@...il.com>, Sergey Senozhatsky <sergey.senozhatsky.work@...il.com> Subject: [PATCHv4 3/6] powerpc64: Add .opd based function descriptor dereference We are moving towards separate kernel and module function descriptor dereference callbacks. This patch enables it for powerpc64. For pointers that belong to the kernel - Added __start_opd and __end_opd pointers, to track the kernel .opd section address range; - Added dereference_kernel_function_descriptor(). Now we will dereference only function pointers that are within [__start_opd, __end_opd); For pointers that belong to a module - Added dereference_module_function_descriptor() to handle module function descriptor dereference. Now we will dereference only pointers that are within [module->opd.start, module->opd.end). Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@...il.com> --- arch/powerpc/include/asm/module.h | 3 +++ arch/powerpc/include/asm/sections.h | 12 ++++++++++++ arch/powerpc/kernel/module_64.c | 14 ++++++++++++++ arch/powerpc/kernel/vmlinux.lds.S | 2 ++ 4 files changed, 31 insertions(+) diff --git a/arch/powerpc/include/asm/module.h b/arch/powerpc/include/asm/module.h index 6c0132c7212f..7e28442827f1 100644 --- a/arch/powerpc/include/asm/module.h +++ b/arch/powerpc/include/asm/module.h @@ -45,6 +45,9 @@ struct mod_arch_specific { unsigned long tramp; #endif + /* For module function descriptor dereference */ + unsigned long start_opd; + unsigned long end_opd; #else /* powerpc64 */ /* Indices of PLT sections within module. */ unsigned int core_plt_section; diff --git a/arch/powerpc/include/asm/sections.h b/arch/powerpc/include/asm/sections.h index 82bec63bbd4f..e335a8f846af 100644 --- a/arch/powerpc/include/asm/sections.h +++ b/arch/powerpc/include/asm/sections.h @@ -66,6 +66,9 @@ static inline int overlaps_kvm_tmp(unsigned long start, unsigned long end) } #ifdef PPC64_ELF_ABI_v1 + +#define HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR 1 + #undef dereference_function_descriptor static inline void *dereference_function_descriptor(void *ptr) { @@ -76,6 +79,15 @@ static inline void *dereference_function_descriptor(void *ptr) ptr = p; return ptr; } + +#undef dereference_kernel_function_descriptor +static inline void *dereference_kernel_function_descriptor(void *ptr) +{ + if (ptr < (void *)__start_opd || ptr >= (void *)__end_opd) + return ptr; + + return dereference_function_descriptor(ptr); +} #endif /* PPC64_ELF_ABI_v1 */ #endif diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c index 759104b99f9f..218971ac7e04 100644 --- a/arch/powerpc/kernel/module_64.c +++ b/arch/powerpc/kernel/module_64.c @@ -93,6 +93,15 @@ static unsigned int local_entry_offset(const Elf64_Sym *sym) { return 0; } + +void *dereference_module_function_descriptor(struct module *mod, void *ptr) +{ + if (ptr < (void *)mod->arch.start_opd || + ptr >= (void *)mod->arch.end_opd) + return ptr; + + return dereference_function_descriptor(ptr); +} #endif #define STUB_MAGIC 0x73747562 /* stub */ @@ -344,6 +353,11 @@ int module_frob_arch_sections(Elf64_Ehdr *hdr, else if (strcmp(secstrings+sechdrs[i].sh_name,"__versions")==0) dedotify_versions((void *)hdr + sechdrs[i].sh_offset, sechdrs[i].sh_size); + else if (!strcmp(secstrings + sechdrs[i].sh_name, ".opd")) { + me->arch.start_opd = sechdrs[i].sh_addr; + me->arch.end_opd = sechdrs[i].sh_addr + + sechdrs[i].sh_size; + } /* We don't handle .init for the moment: rename to _init */ while ((p = strstr(secstrings + sechdrs[i].sh_name, ".init"))) diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S index 0494e1566ee2..5dac5ab22fa2 100644 --- a/arch/powerpc/kernel/vmlinux.lds.S +++ b/arch/powerpc/kernel/vmlinux.lds.S @@ -278,7 +278,9 @@ SECTIONS } .opd : AT(ADDR(.opd) - LOAD_OFFSET) { + __start_opd = .; *(.opd) + __end_opd = .; } . = ALIGN(256); -- 2.15.0
Powered by blists - more mailing lists