| Message ID | 1602918377-23573-2-git-send-email-guoren@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add k/uprobe & fentry & error_injection supported | expand |
On Sat, 17 Oct 2020 00:06:09 PDT (-0700), guoren@kernel.org wrote: > From: Patrick Stählin <me@packi.ch> > > Needed for kprobes support. Copied and adapted from arm64 code. > > Guo Ren fixup pt_regs type for linux-5.8-rc1. > > Signed-off-by: Patrick Stählin <me@packi.ch> > Signed-off-by: Guo Ren <guoren@linux.alibaba.com> > Reviewed-by: Pekka Enberg <penberg@kernel.org> > Reviewed-by: Zong Li <zong.li@sifive.com> > Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> > --- > arch/riscv/Kconfig | 1 + > arch/riscv/include/asm/ptrace.h | 29 ++++++++++++ > arch/riscv/kernel/ptrace.c | 99 +++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 129 insertions(+) > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index b7821ac..e6424d8b 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -87,6 +87,7 @@ config RISCV > select SPARSE_IRQ > select SYSCTL_EXCEPTION_TRACE > select THREAD_INFO_IN_TASK > + select HAVE_REGS_AND_STACK_ACCESS_API We alphabetize these now -- I'd usually just fix it, but there's a Signed-off-by issue later in the patch set. > > config ARCH_MMAP_RND_BITS_MIN > default 18 if 64BIT > diff --git a/arch/riscv/include/asm/ptrace.h b/arch/riscv/include/asm/ptrace.h > index ee49f80..23372bb 100644 > --- a/arch/riscv/include/asm/ptrace.h > +++ b/arch/riscv/include/asm/ptrace.h > @@ -8,6 +8,7 @@ > > #include <uapi/asm/ptrace.h> > #include <asm/csr.h> > +#include <linux/compiler.h> > > #ifndef __ASSEMBLY__ > > @@ -60,6 +61,7 @@ struct pt_regs { > > #define user_mode(regs) (((regs)->status & SR_PP) == 0) > > +#define MAX_REG_OFFSET offsetof(struct pt_regs, orig_a0) > > /* Helpers for working with the instruction pointer */ > static inline unsigned long instruction_pointer(struct pt_regs *regs) > @@ -85,6 +87,12 @@ static inline void user_stack_pointer_set(struct pt_regs *regs, > regs->sp = val; > } > > +/* Valid only for Kernel mode traps. */ > +static inline unsigned long kernel_stack_pointer(struct pt_regs *regs) > +{ > + return regs->sp; > +} > + > /* Helpers for working with the frame pointer */ > static inline unsigned long frame_pointer(struct pt_regs *regs) > { > @@ -101,6 +109,27 @@ static inline unsigned long regs_return_value(struct pt_regs *regs) > return regs->a0; > } > > +extern int regs_query_register_offset(const char *name); > +extern unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, > + unsigned int n); > + > +/** > + * regs_get_register() - get register value from its offset > + * @regs: pt_regs from which register value is gotten > + * @offset: offset of the register. > + * > + * regs_get_register returns the value of a register whose offset from @regs. > + * The @offset is the offset of the register in struct pt_regs. > + * If @offset is bigger than MAX_REG_OFFSET, this returns 0. > + */ > +static inline unsigned long regs_get_register(struct pt_regs *regs, > + unsigned int offset) > +{ > + if (unlikely(offset > MAX_REG_OFFSET)) > + return 0; > + > + return *(unsigned long *)((unsigned long)regs + offset); > +} > #endif /* __ASSEMBLY__ */ > > #endif /* _ASM_RISCV_PTRACE_H */ > diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c > index 2d6395f..1a85305 100644 > --- a/arch/riscv/kernel/ptrace.c > +++ b/arch/riscv/kernel/ptrace.c > @@ -114,6 +114,105 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task) > return &riscv_user_native_view; > } > > +struct pt_regs_offset { > + const char *name; > + int offset; > +}; > + > +#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} > +#define REG_OFFSET_END {.name = NULL, .offset = 0} > + > +static const struct pt_regs_offset regoffset_table[] = { > + REG_OFFSET_NAME(epc), > + REG_OFFSET_NAME(ra), > + REG_OFFSET_NAME(sp), > + REG_OFFSET_NAME(gp), > + REG_OFFSET_NAME(tp), > + REG_OFFSET_NAME(t0), > + REG_OFFSET_NAME(t1), > + REG_OFFSET_NAME(t2), > + REG_OFFSET_NAME(s0), > + REG_OFFSET_NAME(s1), > + REG_OFFSET_NAME(a0), > + REG_OFFSET_NAME(a1), > + REG_OFFSET_NAME(a2), > + REG_OFFSET_NAME(a3), > + REG_OFFSET_NAME(a4), > + REG_OFFSET_NAME(a5), > + REG_OFFSET_NAME(a6), > + REG_OFFSET_NAME(a7), > + REG_OFFSET_NAME(s2), > + REG_OFFSET_NAME(s3), > + REG_OFFSET_NAME(s4), > + REG_OFFSET_NAME(s5), > + REG_OFFSET_NAME(s6), > + REG_OFFSET_NAME(s7), > + REG_OFFSET_NAME(s8), > + REG_OFFSET_NAME(s9), > + REG_OFFSET_NAME(s10), > + REG_OFFSET_NAME(s11), > + REG_OFFSET_NAME(t3), > + REG_OFFSET_NAME(t4), > + REG_OFFSET_NAME(t5), > + REG_OFFSET_NAME(t6), > + REG_OFFSET_NAME(status), > + REG_OFFSET_NAME(badaddr), > + REG_OFFSET_NAME(cause), > + REG_OFFSET_NAME(orig_a0), > + REG_OFFSET_END, > +}; > + > +/** > + * regs_query_register_offset() - query register offset from its name > + * @name: the name of a register > + * > + * regs_query_register_offset() returns the offset of a register in struct > + * pt_regs from its name. If the name is invalid, this returns -EINVAL; > + */ > +int regs_query_register_offset(const char *name) > +{ > + const struct pt_regs_offset *roff; > + > + for (roff = regoffset_table; roff->name != NULL; roff++) > + if (!strcmp(roff->name, name)) > + return roff->offset; > + return -EINVAL; > +} > + > +/** > + * regs_within_kernel_stack() - check the address in the stack > + * @regs: pt_regs which contains kernel stack pointer. > + * @addr: address which is checked. > + * > + * regs_within_kernel_stack() checks @addr is within the kernel stack page(s). > + * If @addr is within the kernel stack, it returns true. If not, returns false. > + */ > +static bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr) > +{ > + return (addr & ~(THREAD_SIZE - 1)) == > + (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1)); > +} > + > +/** > + * regs_get_kernel_stack_nth() - get Nth entry of the stack > + * @regs: pt_regs which contains kernel stack pointer. > + * @n: stack entry number. > + * > + * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which > + * is specified by @regs. If the @n th entry is NOT in the kernel stack, > + * this returns 0. > + */ > +unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n) > +{ > + unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs); > + > + addr += n; > + if (regs_within_kernel_stack(regs, (unsigned long)addr)) > + return *addr; > + else > + return 0; > +} > + > void ptrace_disable(struct task_struct *child) > { > clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
On Fri, Nov 6, 2020 at 9:03 AM Palmer Dabbelt <palmerdabbelt@google.com> wrote: > > On Sat, 17 Oct 2020 00:06:09 PDT (-0700), guoren@kernel.org wrote: > > From: Patrick Stählin <me@packi.ch> > > > > Needed for kprobes support. Copied and adapted from arm64 code. > > > > Guo Ren fixup pt_regs type for linux-5.8-rc1. > > > > Signed-off-by: Patrick Stählin <me@packi.ch> > > Signed-off-by: Guo Ren <guoren@linux.alibaba.com> > > Reviewed-by: Pekka Enberg <penberg@kernel.org> > > Reviewed-by: Zong Li <zong.li@sifive.com> > > Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> > > --- > > arch/riscv/Kconfig | 1 + > > arch/riscv/include/asm/ptrace.h | 29 ++++++++++++ > > arch/riscv/kernel/ptrace.c | 99 +++++++++++++++++++++++++++++++++++++++++ > > 3 files changed, 129 insertions(+) > > > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > > index b7821ac..e6424d8b 100644 > > --- a/arch/riscv/Kconfig > > +++ b/arch/riscv/Kconfig > > @@ -87,6 +87,7 @@ config RISCV > > select SPARSE_IRQ > > select SYSCTL_EXCEPTION_TRACE > > select THREAD_INFO_IN_TASK > > + select HAVE_REGS_AND_STACK_ACCESS_API > > We alphabetize these now -- I'd usually just fix it, but there's a > Signed-off-by issue later in the patch set. ok, I'll fix it and rebase 5.10-rc2.
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index b7821ac..e6424d8b 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -87,6 +87,7 @@ config RISCV select SPARSE_IRQ select SYSCTL_EXCEPTION_TRACE select THREAD_INFO_IN_TASK + select HAVE_REGS_AND_STACK_ACCESS_API config ARCH_MMAP_RND_BITS_MIN default 18 if 64BIT diff --git a/arch/riscv/include/asm/ptrace.h b/arch/riscv/include/asm/ptrace.h index ee49f80..23372bb 100644 --- a/arch/riscv/include/asm/ptrace.h +++ b/arch/riscv/include/asm/ptrace.h @@ -8,6 +8,7 @@ #include <uapi/asm/ptrace.h> #include <asm/csr.h> +#include <linux/compiler.h> #ifndef __ASSEMBLY__ @@ -60,6 +61,7 @@ struct pt_regs { #define user_mode(regs) (((regs)->status & SR_PP) == 0) +#define MAX_REG_OFFSET offsetof(struct pt_regs, orig_a0) /* Helpers for working with the instruction pointer */ static inline unsigned long instruction_pointer(struct pt_regs *regs) @@ -85,6 +87,12 @@ static inline void user_stack_pointer_set(struct pt_regs *regs, regs->sp = val; } +/* Valid only for Kernel mode traps. */ +static inline unsigned long kernel_stack_pointer(struct pt_regs *regs) +{ + return regs->sp; +} + /* Helpers for working with the frame pointer */ static inline unsigned long frame_pointer(struct pt_regs *regs) { @@ -101,6 +109,27 @@ static inline unsigned long regs_return_value(struct pt_regs *regs) return regs->a0; } +extern int regs_query_register_offset(const char *name); +extern unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, + unsigned int n); + +/** + * regs_get_register() - get register value from its offset + * @regs: pt_regs from which register value is gotten + * @offset: offset of the register. + * + * regs_get_register returns the value of a register whose offset from @regs. + * The @offset is the offset of the register in struct pt_regs. + * If @offset is bigger than MAX_REG_OFFSET, this returns 0. + */ +static inline unsigned long regs_get_register(struct pt_regs *regs, + unsigned int offset) +{ + if (unlikely(offset > MAX_REG_OFFSET)) + return 0; + + return *(unsigned long *)((unsigned long)regs + offset); +} #endif /* __ASSEMBLY__ */ #endif /* _ASM_RISCV_PTRACE_H */ diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c index 2d6395f..1a85305 100644 --- a/arch/riscv/kernel/ptrace.c +++ b/arch/riscv/kernel/ptrace.c @@ -114,6 +114,105 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task) return &riscv_user_native_view; } +struct pt_regs_offset { + const char *name; + int offset; +}; + +#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} +#define REG_OFFSET_END {.name = NULL, .offset = 0} + +static const struct pt_regs_offset regoffset_table[] = { + REG_OFFSET_NAME(epc), + REG_OFFSET_NAME(ra), + REG_OFFSET_NAME(sp), + REG_OFFSET_NAME(gp), + REG_OFFSET_NAME(tp), + REG_OFFSET_NAME(t0), + REG_OFFSET_NAME(t1), + REG_OFFSET_NAME(t2), + REG_OFFSET_NAME(s0), + REG_OFFSET_NAME(s1), + REG_OFFSET_NAME(a0), + REG_OFFSET_NAME(a1), + REG_OFFSET_NAME(a2), + REG_OFFSET_NAME(a3), + REG_OFFSET_NAME(a4), + REG_OFFSET_NAME(a5), + REG_OFFSET_NAME(a6), + REG_OFFSET_NAME(a7), + REG_OFFSET_NAME(s2), + REG_OFFSET_NAME(s3), + REG_OFFSET_NAME(s4), + REG_OFFSET_NAME(s5), + REG_OFFSET_NAME(s6), + REG_OFFSET_NAME(s7), + REG_OFFSET_NAME(s8), + REG_OFFSET_NAME(s9), + REG_OFFSET_NAME(s10), + REG_OFFSET_NAME(s11), + REG_OFFSET_NAME(t3), + REG_OFFSET_NAME(t4), + REG_OFFSET_NAME(t5), + REG_OFFSET_NAME(t6), + REG_OFFSET_NAME(status), + REG_OFFSET_NAME(badaddr), + REG_OFFSET_NAME(cause), + REG_OFFSET_NAME(orig_a0), + REG_OFFSET_END, +}; + +/** + * regs_query_register_offset() - query register offset from its name + * @name: the name of a register + * + * regs_query_register_offset() returns the offset of a register in struct + * pt_regs from its name. If the name is invalid, this returns -EINVAL; + */ +int regs_query_register_offset(const char *name) +{ + const struct pt_regs_offset *roff; + + for (roff = regoffset_table; roff->name != NULL; roff++) + if (!strcmp(roff->name, name)) + return roff->offset; + return -EINVAL; +} + +/** + * regs_within_kernel_stack() - check the address in the stack + * @regs: pt_regs which contains kernel stack pointer. + * @addr: address which is checked. + * + * regs_within_kernel_stack() checks @addr is within the kernel stack page(s). + * If @addr is within the kernel stack, it returns true. If not, returns false. + */ +static bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr) +{ + return (addr & ~(THREAD_SIZE - 1)) == + (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1)); +} + +/** + * regs_get_kernel_stack_nth() - get Nth entry of the stack + * @regs: pt_regs which contains kernel stack pointer. + * @n: stack entry number. + * + * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which + * is specified by @regs. If the @n th entry is NOT in the kernel stack, + * this returns 0. + */ +unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n) +{ + unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs); + + addr += n; + if (regs_within_kernel_stack(regs, (unsigned long)addr)) + return *addr; + else + return 0; +} + void ptrace_disable(struct task_struct *child) { clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);