From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergey Senozhatsky Subject: [PATCH 4/5] parisc64: Add .opd based function descriptor dereference Date: Sat, 16 Sep 2017 12:53:46 +0900 Message-ID: <20170916035347.19705-5-sergey.senozhatsky@gmail.com> References: <20170916035347.19705-1-sergey.senozhatsky@gmail.com> Cc: Petr Mladek , Steven Rostedt , Andrew Morton , Jessica Yu , Alexei Starovoitov , linux-ia64@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Sergey Senozhatsky To: Tony Luck , Fenghua Yu , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , "James E . J . Bottomley" , Helge Deller Return-path: In-Reply-To: <20170916035347.19705-1-sergey.senozhatsky@gmail.com> List-ID: List-Id: linux-parisc.vger.kernel.org We are moving towards separate kernel and module function descriptor dereference callbacks. This patch enables it for parisc64. 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 --- arch/parisc/boot/compressed/vmlinux.lds.S | 2 ++ arch/parisc/include/asm/sections.h | 3 +++ arch/parisc/kernel/module.c | 14 ++++++++++++++ arch/parisc/kernel/process.c | 10 ++++++++++ arch/parisc/kernel/vmlinux.lds.S | 2 ++ 5 files changed, 31 insertions(+) diff --git a/arch/parisc/boot/compressed/vmlinux.lds.S b/arch/parisc/boot/compressed/vmlinux.lds.S index a4ce3314e78e..4ebd4e65524c 100644 --- a/arch/parisc/boot/compressed/vmlinux.lds.S +++ b/arch/parisc/boot/compressed/vmlinux.lds.S @@ -29,7 +29,9 @@ SECTIONS . = ALIGN(16); /* Linkage tables */ .opd : { + __start_opd = .; *(.opd) + __end_opd = .; } PROVIDE (__gp = .); .plt : { *(.plt) diff --git a/arch/parisc/include/asm/sections.h b/arch/parisc/include/asm/sections.h index 9d13c3507ad6..e3cde650b2f9 100644 --- a/arch/parisc/include/asm/sections.h +++ b/arch/parisc/include/asm/sections.h @@ -6,7 +6,10 @@ #ifdef CONFIG_64BIT #undef dereference_function_descriptor +#undef dereference_kernel_function_descriptor + void *dereference_function_descriptor(void *); +void *dereference_kernel_function_descriptor(void *); #endif #endif diff --git a/arch/parisc/kernel/module.c b/arch/parisc/kernel/module.c index f1a76935a314..bc2eae8634fd 100644 --- a/arch/parisc/kernel/module.c +++ b/arch/parisc/kernel/module.c @@ -954,3 +954,17 @@ void module_arch_cleanup(struct module *mod) { deregister_unwind_table(mod); } + +#ifdef CONFIG_64BIT +unsigned long dereference_module_function_descriptor(struct module *mod, + unsigned long addr) +{ + void *opd_sz = mod->arch.fdesc_offset + + mod->arch.fdesc_max * sizeof(Elf64_Fdesc); + + if (addr < mod->arch.fdesc_offset || opd_sz < addr) + return addr; + + return dereference_function_descriptor(addr); +} +#endif diff --git a/arch/parisc/kernel/process.c b/arch/parisc/kernel/process.c index 30f92391a93e..f30776bdaa79 100644 --- a/arch/parisc/kernel/process.c +++ b/arch/parisc/kernel/process.c @@ -267,6 +267,8 @@ get_wchan(struct task_struct *p) } #ifdef CONFIG_64BIT +extern char __start_opd[], __end_opd[]; + void *dereference_function_descriptor(void *ptr) { Elf64_Fdesc *desc = ptr; @@ -276,6 +278,14 @@ void *dereference_function_descriptor(void *ptr) ptr = p; return ptr; } + +void *dereference_kernel_function_descriptor(void *ptr) +{ + if (ptr < (void *)__start_opd || (void *)__end_opd < ptr) + return ptr; + + return dereference_function_descriptor(ptr); +} #endif static inline unsigned long brk_rnd(void) diff --git a/arch/parisc/kernel/vmlinux.lds.S b/arch/parisc/kernel/vmlinux.lds.S index ffe2cbf52d1a..ab030895dd1e 100644 --- a/arch/parisc/kernel/vmlinux.lds.S +++ b/arch/parisc/kernel/vmlinux.lds.S @@ -99,7 +99,9 @@ SECTIONS . = ALIGN(16); /* Linkage tables */ .opd : { + __start_opd = .; *(.opd) + __end_opd = .; } PROVIDE (__gp = .); .plt : { *(.plt) -- 2.14.1 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergey Senozhatsky Date: Sat, 16 Sep 2017 03:53:46 +0000 Subject: [PATCH 4/5] parisc64: Add .opd based function descriptor dereference Message-Id: <20170916035347.19705-5-sergey.senozhatsky@gmail.com> List-Id: References: <20170916035347.19705-1-sergey.senozhatsky@gmail.com> In-Reply-To: <20170916035347.19705-1-sergey.senozhatsky@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Tony Luck , Fenghua Yu , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , "James E . J . Bottomley" , Helge Deller Cc: Petr Mladek , Steven Rostedt , Andrew Morton , Jessica Yu , Alexei Starovoitov , linux-ia64@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Sergey Senozhatsky We are moving towards separate kernel and module function descriptor dereference callbacks. This patch enables it for parisc64. 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 --- arch/parisc/boot/compressed/vmlinux.lds.S | 2 ++ arch/parisc/include/asm/sections.h | 3 +++ arch/parisc/kernel/module.c | 14 ++++++++++++++ arch/parisc/kernel/process.c | 10 ++++++++++ arch/parisc/kernel/vmlinux.lds.S | 2 ++ 5 files changed, 31 insertions(+) diff --git a/arch/parisc/boot/compressed/vmlinux.lds.S b/arch/parisc/boot/compressed/vmlinux.lds.S index a4ce3314e78e..4ebd4e65524c 100644 --- a/arch/parisc/boot/compressed/vmlinux.lds.S +++ b/arch/parisc/boot/compressed/vmlinux.lds.S @@ -29,7 +29,9 @@ SECTIONS . = ALIGN(16); /* Linkage tables */ .opd : { + __start_opd = .; *(.opd) + __end_opd = .; } PROVIDE (__gp = .); .plt : { *(.plt) diff --git a/arch/parisc/include/asm/sections.h b/arch/parisc/include/asm/sections.h index 9d13c3507ad6..e3cde650b2f9 100644 --- a/arch/parisc/include/asm/sections.h +++ b/arch/parisc/include/asm/sections.h @@ -6,7 +6,10 @@ #ifdef CONFIG_64BIT #undef dereference_function_descriptor +#undef dereference_kernel_function_descriptor + void *dereference_function_descriptor(void *); +void *dereference_kernel_function_descriptor(void *); #endif #endif diff --git a/arch/parisc/kernel/module.c b/arch/parisc/kernel/module.c index f1a76935a314..bc2eae8634fd 100644 --- a/arch/parisc/kernel/module.c +++ b/arch/parisc/kernel/module.c @@ -954,3 +954,17 @@ void module_arch_cleanup(struct module *mod) { deregister_unwind_table(mod); } + +#ifdef CONFIG_64BIT +unsigned long dereference_module_function_descriptor(struct module *mod, + unsigned long addr) +{ + void *opd_sz = mod->arch.fdesc_offset + + mod->arch.fdesc_max * sizeof(Elf64_Fdesc); + + if (addr < mod->arch.fdesc_offset || opd_sz < addr) + return addr; + + return dereference_function_descriptor(addr); +} +#endif diff --git a/arch/parisc/kernel/process.c b/arch/parisc/kernel/process.c index 30f92391a93e..f30776bdaa79 100644 --- a/arch/parisc/kernel/process.c +++ b/arch/parisc/kernel/process.c @@ -267,6 +267,8 @@ get_wchan(struct task_struct *p) } #ifdef CONFIG_64BIT +extern char __start_opd[], __end_opd[]; + void *dereference_function_descriptor(void *ptr) { Elf64_Fdesc *desc = ptr; @@ -276,6 +278,14 @@ void *dereference_function_descriptor(void *ptr) ptr = p; return ptr; } + +void *dereference_kernel_function_descriptor(void *ptr) +{ + if (ptr < (void *)__start_opd || (void *)__end_opd < ptr) + return ptr; + + return dereference_function_descriptor(ptr); +} #endif static inline unsigned long brk_rnd(void) diff --git a/arch/parisc/kernel/vmlinux.lds.S b/arch/parisc/kernel/vmlinux.lds.S index ffe2cbf52d1a..ab030895dd1e 100644 --- a/arch/parisc/kernel/vmlinux.lds.S +++ b/arch/parisc/kernel/vmlinux.lds.S @@ -99,7 +99,9 @@ SECTIONS . = ALIGN(16); /* Linkage tables */ .opd : { + __start_opd = .; *(.opd) + __end_opd = .; } PROVIDE (__gp = .); .plt : { *(.plt) -- 2.14.1