Messages in this thread Patch in this message | | | Date | Tue, 29 Jun 2021 14:35:16 -0000 | From | Thomas Gleixner <> | Subject | [GIT pull] x86/entry for v5.14-rc1 |
| |
Linus,
please pull the latest x86/entry branch from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-entry-2021-06-29
up to: 48f7eee81cd5: x86/syscalls: Don't adjust CFLAGS for syscall tables
X86 entry code related updates:
- Consolidate the macros for .byte ... opcode sequences
- Deduplicate register offset defines in include files
- Simplify the ia32,x32 compat handling of the related syscall tables to get rid of #ifdeffery.
- Clear all EFLAGS which are not required for syscall handling
- Consolidate the syscall tables and switch the generation over to the generic shell script and remove the CFLAGS tweaks which are not longer required.
- Use 'int' type for system call numbers to match the generic code.
- Add more selftests for syscalls
Thanks,
tglx
------------------> Brian Gerst (3): x86/uml/syscalls: Remove array index from syscall initializers x86/syscalls: Remove -Wno-override-init for syscall tables x86/syscalls: Don't adjust CFLAGS for syscall tables
H. Peter Anvin (1): x86/regs: Syscall_get_nr() returns -1 for a non-system call
H. Peter Anvin (Intel) (14): x86/asm: Have the __ASM_FORM macros handle commas in arguments x86/asm: Add _ASM_BYTES() macro for a .byte ... opcode sequence x86/asm: Use _ASM_BYTES() in <asm/nops.h> x86/entry: Unify definitions from <asm/calling.h> and <asm/ptrace-abi.h> x86/entry: Reverse arguments to do_syscall_64() x86/syscall: Unconditionally prototype {ia32,x32}_sys_call_table[] x86/syscall: Maximize MSR_SYSCALL_MASK x86/entry: Split PUSH_AND_CLEAR_REGS into two submacros selftests/x86/syscall: Update and extend syscall_numbering_64 selftests/x86/syscall: Simplify message reporting in syscall_numbering selftests/x86/syscall: Add tests under ptrace to syscall_numbering_64 x86/entry/64: Sign-extend system calls on entry to int x86/entry: Treat out of range and gap system calls the same x86/entry: Use int everywhere for system call numbers
Ingo Molnar (1): x86/asm: Make <asm/asm.h> valid on cross-builds as well
Masahiro Yamada (7): x86/entry/x32: Rename __x32_compat_sys_* to __x64_compat_sys_* x86/syscalls: Switch to generic syscalltbl.sh x86/syscalls: Stop filling syscall arrays with *_sys_ni_syscall x86/unistd: Define X32_NR_syscalls only for 64-bit kernel x86/syscalls: Use __NR_syscalls instead of __NR_syscall_max x86/syscalls: Switch to generic syscallhdr.sh x86/syscalls: Clear 'offset' and 'prefix' in case they are set in env
arch/um/kernel/skas/syscall.c | 2 +- arch/x86/entry/Makefile | 10 - arch/x86/entry/calling.h | 45 +-- arch/x86/entry/common.c | 87 +++-- arch/x86/entry/entry_64.S | 5 +- arch/x86/entry/syscall_32.c | 20 +- arch/x86/entry/syscall_64.c | 17 +- arch/x86/entry/syscall_x32.c | 35 +- arch/x86/entry/syscalls/Makefile | 38 +- arch/x86/entry/syscalls/syscallhdr.sh | 35 -- arch/x86/entry/syscalls/syscalltbl.sh | 46 --- arch/x86/include/asm/Kbuild | 1 + arch/x86/include/asm/asm.h | 27 +- arch/x86/include/asm/nops.h | 24 +- arch/x86/include/asm/syscall.h | 13 +- arch/x86/include/asm/syscall_wrapper.h | 10 +- arch/x86/include/asm/unistd.h | 8 +- arch/x86/kernel/cpu/common.c | 12 +- arch/x86/kernel/head_64.S | 6 +- arch/x86/kernel/ptrace.c | 2 +- arch/x86/kernel/signal.c | 4 +- arch/x86/um/sys_call_table_32.c | 14 +- arch/x86/um/sys_call_table_64.c | 15 +- tools/arch/x86/include/asm/asm.h | 193 ++++++++++ tools/arch/x86/include/asm/nops.h | 24 +- tools/testing/selftests/x86/syscall_numbering.c | 491 +++++++++++++++++++++--- 26 files changed, 827 insertions(+), 357 deletions(-) delete mode 100644 arch/x86/entry/syscalls/syscallhdr.sh delete mode 100644 arch/x86/entry/syscalls/syscalltbl.sh create mode 100644 tools/arch/x86/include/asm/asm.h
diff --git a/arch/um/kernel/skas/syscall.c b/arch/um/kernel/skas/syscall.c index 3d91f89fd852..9ee19e566da3 100644 --- a/arch/um/kernel/skas/syscall.c +++ b/arch/um/kernel/skas/syscall.c @@ -41,7 +41,7 @@ void handle_syscall(struct uml_pt_regs *r) goto out; syscall = UPT_SYSCALL_NR(r); - if (syscall >= 0 && syscall <= __NR_syscall_max) + if (syscall >= 0 && syscall < __NR_syscalls) PT_REGS_SET_SYSCALL_RETURN(regs, EXECUTE_SYSCALL(syscall, regs)); diff --git a/arch/x86/entry/Makefile b/arch/x86/entry/Makefile index 08bf95dbc911..7fec5dcf6438 100644 --- a/arch/x86/entry/Makefile +++ b/arch/x86/entry/Makefile @@ -8,18 +8,8 @@ UBSAN_SANITIZE := n KCOV_INSTRUMENT := n CFLAGS_REMOVE_common.o = $(CC_FLAGS_FTRACE) -CFLAGS_REMOVE_syscall_64.o = $(CC_FLAGS_FTRACE) -CFLAGS_REMOVE_syscall_32.o = $(CC_FLAGS_FTRACE) -CFLAGS_REMOVE_syscall_x32.o = $(CC_FLAGS_FTRACE) CFLAGS_common.o += -fno-stack-protector -CFLAGS_syscall_64.o += -fno-stack-protector -CFLAGS_syscall_32.o += -fno-stack-protector -CFLAGS_syscall_x32.o += -fno-stack-protector - -CFLAGS_syscall_64.o += $(call cc-option,-Wno-override-init,) -CFLAGS_syscall_32.o += $(call cc-option,-Wno-override-init,) -CFLAGS_syscall_x32.o += $(call cc-option,-Wno-override-init,) obj-y := entry_$(BITS).o thunk_$(BITS).o syscall_$(BITS).o obj-y += common.o diff --git a/arch/x86/entry/calling.h b/arch/x86/entry/calling.h index 07a9331d55e7..a4c061fb7c6e 100644 --- a/arch/x86/entry/calling.h +++ b/arch/x86/entry/calling.h @@ -6,6 +6,7 @@ #include <asm/percpu.h> #include <asm/asm-offsets.h> #include <asm/processor-flags.h> +#include <asm/ptrace-abi.h> /* @@ -62,42 +63,7 @@ For 32-bit we have the following conventions - kernel is built with * for assembly code: */ -/* The layout forms the "struct pt_regs" on the stack: */ -/* - * C ABI says these regs are callee-preserved. They aren't saved on kernel entry - * unless syscall needs a complete, fully filled "struct pt_regs". - */ -#define R15 0*8 -#define R14 1*8 -#define R13 2*8 -#define R12 3*8 -#define RBP 4*8 -#define RBX 5*8 -/* These regs are callee-clobbered. Always saved on kernel entry. */ -#define R11 6*8 -#define R10 7*8 -#define R9 8*8 -#define R8 9*8 -#define RAX 10*8 -#define RCX 11*8 -#define RDX 12*8 -#define RSI 13*8 -#define RDI 14*8 -/* - * On syscall entry, this is syscall#. On CPU exception, this is error code. - * On hw interrupt, it's IRQ number: - */ -#define ORIG_RAX 15*8 -/* Return frame for iretq */ -#define RIP 16*8 -#define CS 17*8 -#define EFLAGS 18*8 -#define RSP 19*8 -#define SS 20*8 - -#define SIZEOF_PTREGS 21*8 - -.macro PUSH_AND_CLEAR_REGS rdx=%rdx rax=%rax save_ret=0 +.macro PUSH_REGS rdx=%rdx rax=%rax save_ret=0 .if \save_ret pushq %rsi /* pt_regs->si */ movq 8(%rsp), %rsi /* temporarily store the return address in %rsi */ @@ -124,7 +90,9 @@ For 32-bit we have the following conventions - kernel is built with .if \save_ret pushq %rsi /* return address on top of stack */ .endif +.endm +.macro CLEAR_REGS /* * Sanitize registers of values that a speculation attack might * otherwise want to exploit. The lower registers are likely clobbered @@ -146,6 +114,11 @@ For 32-bit we have the following conventions - kernel is built with .endm +.macro PUSH_AND_CLEAR_REGS rdx=%rdx rax=%rax save_ret=0 + PUSH_REGS rdx=\rdx, rax=\rax, save_ret=\save_ret + CLEAR_REGS +.endm + .macro POP_REGS pop_rdi=1 skip_r11rcx=0 popq %r15 popq %r14 diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index 7b2542b13ebd..ee95fe3f1518 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -36,61 +36,97 @@ #include <asm/irq_stack.h> #ifdef CONFIG_X86_64 -__visible noinstr void do_syscall_64(unsigned long nr, struct pt_regs *regs) + +static __always_inline bool do_syscall_x64(struct pt_regs *regs, int nr) +{ + /* + * Convert negative numbers to very high and thus out of range + * numbers for comparisons. + */ + unsigned int unr = nr; + + if (likely(unr < NR_syscalls)) { + unr = array_index_nospec(unr, NR_syscalls); + regs->ax = sys_call_table[unr](regs); + return true; + } + return false; +} + +static __always_inline bool do_syscall_x32(struct pt_regs *regs, int nr) +{ + /* + * Adjust the starting offset of the table, and convert numbers + * < __X32_SYSCALL_BIT to very high and thus out of range + * numbers for comparisons. + */ + unsigned int xnr = nr - __X32_SYSCALL_BIT; + + if (IS_ENABLED(CONFIG_X86_X32_ABI) && likely(xnr < X32_NR_syscalls)) { + xnr = array_index_nospec(xnr, X32_NR_syscalls); + regs->ax = x32_sys_call_table[xnr](regs); + return true; + } + return false; +} + +__visible noinstr void do_syscall_64(struct pt_regs *regs, int nr) { add_random_kstack_offset(); nr = syscall_enter_from_user_mode(regs, nr); instrumentation_begin(); - if (likely(nr < NR_syscalls)) { - nr = array_index_nospec(nr, NR_syscalls); - regs->ax = sys_call_table[nr](regs); -#ifdef CONFIG_X86_X32_ABI - } else if (likely((nr & __X32_SYSCALL_BIT) && - (nr & ~__X32_SYSCALL_BIT) < X32_NR_syscalls)) { - nr = array_index_nospec(nr & ~__X32_SYSCALL_BIT, - X32_NR_syscalls); - regs->ax = x32_sys_call_table[nr](regs); -#endif + + if (!do_syscall_x64(regs, nr) && !do_syscall_x32(regs, nr) && nr != -1) { + /* Invalid system call, but still a system call. */ + regs->ax = __x64_sys_ni_syscall(regs); } + instrumentation_end(); syscall_exit_to_user_mode(regs); } #endif #if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION) -static __always_inline unsigned int syscall_32_enter(struct pt_regs *regs) +static __always_inline int syscall_32_enter(struct pt_regs *regs) { if (IS_ENABLED(CONFIG_IA32_EMULATION)) current_thread_info()->status |= TS_COMPAT; - return (unsigned int)regs->orig_ax; + return (int)regs->orig_ax; } /* * Invoke a 32-bit syscall. Called with IRQs on in CONTEXT_KERNEL. */ -static __always_inline void do_syscall_32_irqs_on(struct pt_regs *regs, - unsigned int nr) +static __always_inline void do_syscall_32_irqs_on(struct pt_regs *regs, int nr) { - if (likely(nr < IA32_NR_syscalls)) { - nr = array_index_nospec(nr, IA32_NR_syscalls); - regs->ax = ia32_sys_call_table[nr](regs); + /* + * Convert negative numbers to very high and thus out of range + * numbers for comparisons. + */ + unsigned int unr = nr; + + if (likely(unr < IA32_NR_syscalls)) { + unr = array_index_nospec(unr, IA32_NR_syscalls); + regs->ax = ia32_sys_call_table[unr](regs); + } else if (nr != -1) { + regs->ax = __ia32_sys_ni_syscall(regs); } } /* Handles int $0x80 */ __visible noinstr void do_int80_syscall_32(struct pt_regs *regs) { - unsigned int nr = syscall_32_enter(regs); + int nr = syscall_32_enter(regs); add_random_kstack_offset(); /* - * Subtlety here: if ptrace pokes something larger than 2^32-1 into - * orig_ax, the unsigned int return value truncates it. This may - * or may not be necessary, but it matches the old asm behavior. + * Subtlety here: if ptrace pokes something larger than 2^31-1 into + * orig_ax, the int return value truncates it. This matches + * the semantics of syscall_get_nr(). */ - nr = (unsigned int)syscall_enter_from_user_mode(regs, nr); + nr = syscall_enter_from_user_mode(regs, nr); instrumentation_begin(); do_syscall_32_irqs_on(regs, nr); @@ -101,7 +137,7 @@ __visible noinstr void do_int80_syscall_32(struct pt_regs *regs) static noinstr bool __do_fast_syscall_32(struct pt_regs *regs) { - unsigned int nr = syscall_32_enter(regs); + int nr = syscall_32_enter(regs); int res; add_random_kstack_offset(); @@ -136,8 +172,7 @@ static noinstr bool __do_fast_syscall_32(struct pt_regs *regs) return false; } - /* The case truncates any ptrace induced syscall nr > 2^32 -1 */ - nr = (unsigned int)syscall_enter_from_user_mode_work(regs, nr); + nr = syscall_enter_from_user_mode_work(regs, nr); /* Now this is just like a normal syscall. */ do_syscall_32_irqs_on(regs, nr); diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index a16a5294d55f..a5f02d03c585 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -107,8 +107,9 @@ SYM_INNER_LABEL(entry_SYSCALL_64_after_hwframe, SYM_L_GLOBAL) PUSH_AND_CLEAR_REGS rax=$-ENOSYS /* IRQs are off. */ - movq %rax, %rdi - movq %rsp, %rsi + movq %rsp, %rdi + /* Sign extend the lower 32bit as syscall numbers are treated as int */ + movslq %eax, %rsi call do_syscall_64 /* returns with IRQs disabled */ /* diff --git a/arch/x86/entry/syscall_32.c b/arch/x86/entry/syscall_32.c index 86eb0d89d46f..8cfc9bc73e7f 100644 --- a/arch/x86/entry/syscall_32.c +++ b/arch/x86/entry/syscall_32.c @@ -5,21 +5,21 @@ #include <linux/sys.h> #include <linux/cache.h> #include <linux/syscalls.h> -#include <asm/unistd.h> #include <asm/syscall.h> -#define __SYSCALL_I386(nr, sym) extern long __ia32_##sym(const struct pt_regs *); +#ifdef CONFIG_IA32_EMULATION +#define __SYSCALL_WITH_COMPAT(nr, native, compat) __SYSCALL(nr, compat) +#else +#define __SYSCALL_WITH_COMPAT(nr, native, compat) __SYSCALL(nr, native) +#endif + +#define __SYSCALL(nr, sym) extern long __ia32_##sym(const struct pt_regs *); #include <asm/syscalls_32.h> -#undef __SYSCALL_I386 +#undef __SYSCALL -#define __SYSCALL_I386(nr, sym) [nr] = __ia32_##sym, +#define __SYSCALL(nr, sym) __ia32_##sym, -__visible const sys_call_ptr_t ia32_sys_call_table[__NR_ia32_syscall_max+1] = { - /* - * Smells like a compiler bug -- it doesn't work - * when the & below is removed. - */ - [0 ... __NR_ia32_syscall_max] = &__ia32_sys_ni_syscall, +__visible const sys_call_ptr_t ia32_sys_call_table[] = { #include <asm/syscalls_32.h> }; diff --git a/arch/x86/entry/syscall_64.c b/arch/x86/entry/syscall_64.c index 1594ec72bcbb..be120eec1fc9 100644 --- a/arch/x86/entry/syscall_64.c +++ b/arch/x86/entry/syscall_64.c @@ -5,23 +5,14 @@ #include <linux/sys.h> #include <linux/cache.h> #include <linux/syscalls.h> -#include <asm/unistd.h> #include <asm/syscall.h> -#define __SYSCALL_X32(nr, sym) -#define __SYSCALL_COMMON(nr, sym) __SYSCALL_64(nr, sym) - -#define __SYSCALL_64(nr, sym) extern long __x64_##sym(const struct pt_regs *); +#define __SYSCALL(nr, sym) extern long __x64_##sym(const struct pt_regs *); #include <asm/syscalls_64.h> -#undef __SYSCALL_64 +#undef __SYSCALL -#define __SYSCALL_64(nr, sym) [nr] = __x64_##sym, +#define __SYSCALL(nr, sym) __x64_##sym, -asmlinkage const sys_call_ptr_t sys_call_table[__NR_syscall_max+1] = { - /* - * Smells like a compiler bug -- it doesn't work - * when the & below is removed. - */ - [0 ... __NR_syscall_max] = &__x64_sys_ni_syscall, +asmlinkage const sys_call_ptr_t sys_call_table[] = { #include <asm/syscalls_64.h> }; diff --git a/arch/x86/entry/syscall_x32.c b/arch/x86/entry/syscall_x32.c index f2fe0a33bcfd..bdd0e03a1265 100644 --- a/arch/x86/entry/syscall_x32.c +++ b/arch/x86/entry/syscall_x32.c @@ -5,37 +5,14 @@ #include <linux/sys.h> #include <linux/cache.h> #include <linux/syscalls.h> -#include <asm/unistd.h> #include <asm/syscall.h> -/* - * Reuse the 64-bit entry points for the x32 versions that occupy different - * slots in the syscall table. - */ -#define __x32_sys_readv __x64_sys_readv -#define __x32_sys_writev __x64_sys_writev -#define __x32_sys_getsockopt __x64_sys_getsockopt -#define __x32_sys_setsockopt __x64_sys_setsockopt -#define __x32_sys_vmsplice __x64_sys_vmsplice -#define __x32_sys_process_vm_readv __x64_sys_process_vm_readv -#define __x32_sys_process_vm_writev __x64_sys_process_vm_writev +#define __SYSCALL(nr, sym) extern long __x64_##sym(const struct pt_regs *); +#include <asm/syscalls_x32.h> +#undef __SYSCALL -#define __SYSCALL_64(nr, sym) +#define __SYSCALL(nr, sym) __x64_##sym, -#define __SYSCALL_X32(nr, sym) extern long __x32_##sym(const struct pt_regs *); -#define __SYSCALL_COMMON(nr, sym) extern long __x64_##sym(const struct pt_regs *); -#include <asm/syscalls_64.h> -#undef __SYSCALL_X32 -#undef __SYSCALL_COMMON - -#define __SYSCALL_X32(nr, sym) [nr] = __x32_##sym, -#define __SYSCALL_COMMON(nr, sym) [nr] = __x64_##sym, - -asmlinkage const sys_call_ptr_t x32_sys_call_table[__NR_x32_syscall_max+1] = { - /* - * Smells like a compiler bug -- it doesn't work - * when the & below is removed. - */ - [0 ... __NR_x32_syscall_max] = &__x64_sys_ni_syscall, -#include <asm/syscalls_64.h> +asmlinkage const sys_call_ptr_t x32_sys_call_table[] = { +#include <asm/syscalls_x32.h> }; diff --git a/arch/x86/entry/syscalls/Makefile b/arch/x86/entry/syscalls/Makefile index d8c4f6c9eadc..5b3efed0e4e8 100644 --- a/arch/x86/entry/syscalls/Makefile +++ b/arch/x86/entry/syscalls/Makefile @@ -9,47 +9,54 @@ _dummy := $(shell [ -d '$(out)' ] || mkdir -p '$(out)') \ syscall32 := $(src)/syscall_32.tbl syscall64 := $(src)/syscall_64.tbl -syshdr := $(srctree)/$(src)/syscallhdr.sh -systbl := $(srctree)/$(src)/syscalltbl.sh +syshdr := $(srctree)/scripts/syscallhdr.sh +systbl := $(srctree)/scripts/syscalltbl.sh +offset := +prefix := quiet_cmd_syshdr = SYSHDR $@ - cmd_syshdr = $(CONFIG_SHELL) '$(syshdr)' '$<' '$@' \ - '$(syshdr_abi_$(basetarget))' \ - '$(syshdr_pfx_$(basetarget))' \ - '$(syshdr_offset_$(basetarget))' + cmd_syshdr = $(CONFIG_SHELL) $(syshdr) --abis $(abis) --emit-nr \ + $(if $(offset),--offset $(offset)) \ + $(if $(prefix),--prefix $(prefix)) \ + $< $@ quiet_cmd_systbl = SYSTBL $@ - cmd_systbl = $(CONFIG_SHELL) '$(systbl)' $< $@ + cmd_systbl = $(CONFIG_SHELL) $(systbl) --abis $(abis) $< $@ quiet_cmd_hypercalls = HYPERCALLS $@ cmd_hypercalls = $(CONFIG_SHELL) '$<' $@ $(filter-out $<, $(real-prereqs)) -syshdr_abi_unistd_32 := i386 +$(uapi)/unistd_32.h: abis := i386 $(uapi)/unistd_32.h: $(syscall32) $(syshdr) FORCE $(call if_changed,syshdr) -syshdr_abi_unistd_32_ia32 := i386 -syshdr_pfx_unistd_32_ia32 := ia32_ +$(out)/unistd_32_ia32.h: abis := i386 +$(out)/unistd_32_ia32.h: prefix := ia32_ $(out)/unistd_32_ia32.h: $(syscall32) $(syshdr) FORCE $(call if_changed,syshdr) -syshdr_abi_unistd_x32 := common,x32 -syshdr_offset_unistd_x32 := __X32_SYSCALL_BIT +$(uapi)/unistd_x32.h: abis := common,x32 +$(uapi)/unistd_x32.h: offset := __X32_SYSCALL_BIT $(uapi)/unistd_x32.h: $(syscall64) $(syshdr) FORCE $(call if_changed,syshdr) -syshdr_abi_unistd_64 := common,64 +$(uapi)/unistd_64.h: abis := common,64 $(uapi)/unistd_64.h: $(syscall64) $(syshdr) FORCE $(call if_changed,syshdr) -syshdr_abi_unistd_64_x32 := x32 -syshdr_pfx_unistd_64_x32 := x32_ +$(out)/unistd_64_x32.h: abis := x32 +$(out)/unistd_64_x32.h: prefix := x32_ $(out)/unistd_64_x32.h: $(syscall64) $(syshdr) FORCE $(call if_changed,syshdr) +$(out)/syscalls_32.h: abis := i386 $(out)/syscalls_32.h: $(syscall32) $(systbl) FORCE $(call if_changed,systbl) +$(out)/syscalls_64.h: abis := common,64 $(out)/syscalls_64.h: $(syscall64) $(systbl) FORCE $(call if_changed,systbl) +$(out)/syscalls_x32.h: abis := common,x32 +$(out)/syscalls_x32.h: $(syscall64) $(systbl) FORCE + $(call if_changed,systbl) $(out)/xen-hypercalls.h: $(srctree)/scripts/xen-hypercalls.sh FORCE $(call if_changed,hypercalls) @@ -60,6 +67,7 @@ uapisyshdr-y += unistd_32.h unistd_64.h unistd_x32.h syshdr-y += syscalls_32.h syshdr-$(CONFIG_X86_64) += unistd_32_ia32.h unistd_64_x32.h syshdr-$(CONFIG_X86_64) += syscalls_64.h +syshdr-$(CONFIG_X86_X32) += syscalls_x32.h syshdr-$(CONFIG_XEN) += xen-hypercalls.h uapisyshdr-y := $(addprefix $(uapi)/, $(uapisyshdr-y)) diff --git a/arch/x86/entry/syscalls/syscallhdr.sh b/arch/x86/entry/syscalls/syscallhdr.sh deleted file mode 100644 index cc1e63857427..000000000000 --- a/arch/x86/entry/syscalls/syscallhdr.sh +++ /dev/null @@ -1,35 +0,0 @@ -#!/bin/sh -# SPDX-License-Identifier: GPL-2.0 - -in="$1" -out="$2" -my_abis=`echo "($3)" | tr ',' '|'` -prefix="$4" -offset="$5" - -fileguard=_ASM_X86_`basename "$out" | sed \ - -e 'y/abcdefghijklmnopqrstuvwxyz/ABCDEFGHIJKLMNOPQRSTUVWXYZ/' \ - -e 's/[^A-Z0-9_]/_/g' -e 's/__/_/g'` -grep -E "^[0-9A-Fa-fXx]+[[:space:]]+${my_abis}" "$in" | sort -n | ( - echo "#ifndef ${fileguard}" - echo "#define ${fileguard} 1" - echo "" - - max=0 - while read nr abi name entry ; do - if [ -z "$offset" ]; then - echo "#define __NR_${prefix}${name} $nr" - else - echo "#define __NR_${prefix}${name} ($offset + $nr)" - fi - - max=$nr - done - - echo "" - echo "#ifdef __KERNEL__" - echo "#define __NR_${prefix}syscall_max $max" - echo "#endif" - echo "" - echo "#endif /* ${fileguard} */" -) > "$out" diff --git a/arch/x86/entry/syscalls/syscalltbl.sh b/arch/x86/entry/syscalls/syscalltbl.sh deleted file mode 100644 index 929bde120d6b..000000000000 --- a/arch/x86/entry/syscalls/syscalltbl.sh +++ /dev/null @@ -1,46 +0,0 @@ -#!/bin/bash -# SPDX-License-Identifier: GPL-2.0 - -in="$1" -out="$2" - -syscall_macro() { - local abi="$1" - local nr="$2" - local entry="$3" - - echo "__SYSCALL_${abi}($nr, $entry)" -} - -emit() { - local abi="$1" - local nr="$2" - local entry="$3" - local compat="$4" - - if [ "$abi" != "I386" -a -n "$compat" ]; then - echo "a compat entry ($abi: $compat) for a 64-bit syscall makes no sense" >&2 - exit 1 - fi - - if [ -z "$compat" ]; then - if [ -n "$entry" ]; then - syscall_macro "$abi" "$nr" "$entry" - fi - else - echo "#ifdef CONFIG_X86_32" - if [ -n "$entry" ]; then - syscall_macro "$abi" "$nr" "$entry" - fi - echo "#else" - syscall_macro "$abi" "$nr" "$compat" - echo "#endif" - fi -} - -grep '^[0-9]' "$in" | sort -n | ( - while read nr abi name entry compat; do - abi=`echo "$abi" | tr '[a-z]' '[A-Z]'` - emit "$abi" "$nr" "$entry" "$compat" - done -) > "$out" diff --git a/arch/x86/include/asm/Kbuild b/arch/x86/include/asm/Kbuild index b19ec8282d50..1e51650b79d7 100644 --- a/arch/x86/include/asm/Kbuild +++ b/arch/x86/include/asm/Kbuild @@ -3,6 +3,7 @@ generated-y += syscalls_32.h generated-y += syscalls_64.h +generated-y += syscalls_x32.h generated-y += unistd_32_ia32.h generated-y += unistd_64_x32.h generated-y += xen-hypercalls.h diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h index 0603c7423aca..3ad3da9a7d97 100644 --- a/arch/x86/include/asm/asm.h +++ b/arch/x86/include/asm/asm.h @@ -3,25 +3,26 @@ #define _ASM_X86_ASM_H #ifdef __ASSEMBLY__ -# define __ASM_FORM(x) x -# define __ASM_FORM_RAW(x) x -# define __ASM_FORM_COMMA(x) x, +# define __ASM_FORM(x, ...) x,## __VA_ARGS__ +# define __ASM_FORM_RAW(x, ...) x,## __VA_ARGS__ +# define __ASM_FORM_COMMA(x, ...) x,## __VA_ARGS__, #else #include <linux/stringify.h> - -# define __ASM_FORM(x) " " __stringify(x) " " -# define __ASM_FORM_RAW(x) __stringify(x) -# define __ASM_FORM_COMMA(x) " " __stringify(x) "," +# define __ASM_FORM(x, ...) " " __stringify(x,##__VA_ARGS__) " " +# define __ASM_FORM_RAW(x, ...) __stringify(x,##__VA_ARGS__) +# define __ASM_FORM_COMMA(x, ...) " " __stringify(x,##__VA_ARGS__) "," #endif +#define _ASM_BYTES(x, ...) __ASM_FORM(.byte x,##__VA_ARGS__ ;) + #ifndef __x86_64__ /* 32 bit */ -# define __ASM_SEL(a,b) __ASM_FORM(a) -# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(a) +# define __ASM_SEL(a,b) __ASM_FORM(a) +# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(a) #else /* 64 bit */ -# define __ASM_SEL(a,b) __ASM_FORM(b) -# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(b) +# define __ASM_SEL(a,b) __ASM_FORM(b) +# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(b) #endif #define __ASM_SIZE(inst, ...) __ASM_SEL(inst##l##__VA_ARGS__, \ @@ -119,6 +120,8 @@ # define CC_OUT(c) [_cc_ ## c] "=qm" #endif +#ifdef __KERNEL__ + /* Exception table entry */ #ifdef __ASSEMBLY__ # define _ASM_EXTABLE_HANDLE(from, to, handler) \ @@ -185,4 +188,6 @@ register unsigned long current_stack_pointer asm(_ASM_SP); #define ASM_CALL_CONSTRAINT "+r" (current_stack_pointer) #endif /* __ASSEMBLY__ */ +#endif /* __KERNEL__ */ + #endif /* _ASM_X86_ASM_H */ diff --git a/arch/x86/include/asm/nops.h b/arch/x86/include/asm/nops.h index c1e5e818ba16..c5573eaa5bb9 100644 --- a/arch/x86/include/asm/nops.h +++ b/arch/x86/include/asm/nops.h @@ -2,6 +2,8 @@ #ifndef _ASM_X86_NOPS_H #define _ASM_X86_NOPS_H +#include <asm/asm.h> + /* * Define nops for use with alternative() and for tracing. */ @@ -57,20 +59,14 @@ #endif /* CONFIG_64BIT */ -#ifdef __ASSEMBLY__ -#define _ASM_MK_NOP(x) .byte x -#else -#define _ASM_MK_NOP(x) ".byte " __stringify(x) "\n" -#endif - -#define ASM_NOP1 _ASM_MK_NOP(BYTES_NOP1) -#define ASM_NOP2 _ASM_MK_NOP(BYTES_NOP2) -#define ASM_NOP3 _ASM_MK_NOP(BYTES_NOP3) -#define ASM_NOP4 _ASM_MK_NOP(BYTES_NOP4) -#define ASM_NOP5 _ASM_MK_NOP(BYTES_NOP5) -#define ASM_NOP6 _ASM_MK_NOP(BYTES_NOP6) -#define ASM_NOP7 _ASM_MK_NOP(BYTES_NOP7) -#define ASM_NOP8 _ASM_MK_NOP(BYTES_NOP8) +#define ASM_NOP1 _ASM_BYTES(BYTES_NOP1) +#define ASM_NOP2 _ASM_BYTES(BYTES_NOP2) +#define ASM_NOP3 _ASM_BYTES(BYTES_NOP3) +#define ASM_NOP4 _ASM_BYTES(BYTES_NOP4) +#define ASM_NOP5 _ASM_BYTES(BYTES_NOP5) +#define ASM_NOP6 _ASM_BYTES(BYTES_NOP6) +#define ASM_NOP7 _ASM_BYTES(BYTES_NOP7) +#define ASM_NOP8 _ASM_BYTES(BYTES_NOP8) #define ASM_NOP_MAX 8 diff --git a/arch/x86/include/asm/syscall.h b/arch/x86/include/asm/syscall.h index 7cbf733d11af..f7e2d82d24fb 100644 --- a/arch/x86/include/asm/syscall.h +++ b/arch/x86/include/asm/syscall.h @@ -21,13 +21,12 @@ extern const sys_call_ptr_t sys_call_table[]; #if defined(CONFIG_X86_32) #define ia32_sys_call_table sys_call_table -#endif - -#if defined(CONFIG_IA32_EMULATION) +#else +/* + * These may not exist, but still put the prototypes in so we + * can use IS_ENABLED(). + */ extern const sys_call_ptr_t ia32_sys_call_table[]; -#endif - -#ifdef CONFIG_X86_X32_ABI extern const sys_call_ptr_t x32_sys_call_table[]; #endif @@ -160,7 +159,7 @@ static inline int syscall_get_arch(struct task_struct *task) ? AUDIT_ARCH_I386 : AUDIT_ARCH_X86_64; } -void do_syscall_64(unsigned long nr, struct pt_regs *regs); +void do_syscall_64(struct pt_regs *regs, int nr); void do_int80_syscall_32(struct pt_regs *regs); long do_fast_syscall_32(struct pt_regs *regs); diff --git a/arch/x86/include/asm/syscall_wrapper.h b/arch/x86/include/asm/syscall_wrapper.h index 80c08c7d5e72..6a2827d0681f 100644 --- a/arch/x86/include/asm/syscall_wrapper.h +++ b/arch/x86/include/asm/syscall_wrapper.h @@ -17,7 +17,7 @@ extern long __ia32_sys_ni_syscall(const struct pt_regs *regs); * __x64_sys_*() - 64-bit native syscall * __ia32_sys_*() - 32-bit native syscall or common compat syscall * __ia32_compat_sys_*() - 32-bit compat syscall - * __x32_compat_sys_*() - 64-bit X32 compat syscall + * __x64_compat_sys_*() - 64-bit X32 compat syscall * * The registers are decoded according to the ABI: * 64-bit: RDI, RSI, RDX, R10, R8, R9 @@ -166,17 +166,17 @@ extern long __ia32_sys_ni_syscall(const struct pt_regs *regs); * with x86_64 obviously do not need such care. */ #define __X32_COMPAT_SYS_STUB0(name) \ - __SYS_STUB0(x32, compat_sys_##name) + __SYS_STUB0(x64, compat_sys_##name) #define __X32_COMPAT_SYS_STUBx(x, name, ...) \ - __SYS_STUBx(x32, compat_sys##name, \ + __SYS_STUBx(x64, compat_sys##name, \ SC_X86_64_REGS_TO_ARGS(x, __VA_ARGS__)) #define __X32_COMPAT_COND_SYSCALL(name) \ - __COND_SYSCALL(x32, compat_sys_##name) + __COND_SYSCALL(x64, compat_sys_##name) #define __X32_COMPAT_SYS_NI(name) \ - __SYS_NI(x32, compat_sys_##name) + __SYS_NI(x64, compat_sys_##name) #else /* CONFIG_X86_X32 */ #define __X32_COMPAT_SYS_STUB0(name) #define __X32_COMPAT_SYS_STUBx(x, name, ...) diff --git a/arch/x86/include/asm/unistd.h b/arch/x86/include/asm/unistd.h index c1c3d31b15c0..80e9d5206a71 100644 --- a/arch/x86/include/asm/unistd.h +++ b/arch/x86/include/asm/unistd.h @@ -13,7 +13,7 @@ # define __ARCH_WANT_SYS_OLD_MMAP # define __ARCH_WANT_SYS_OLD_SELECT -# define __NR_ia32_syscall_max __NR_syscall_max +# define IA32_NR_syscalls (__NR_syscalls) # else @@ -26,12 +26,12 @@ # define __ARCH_WANT_COMPAT_SYS_PWRITEV64 # define __ARCH_WANT_COMPAT_SYS_PREADV64V2 # define __ARCH_WANT_COMPAT_SYS_PWRITEV64V2 +# define X32_NR_syscalls (__NR_x32_syscalls) +# define IA32_NR_syscalls (__NR_ia32_syscalls) # endif -# define NR_syscalls (__NR_syscall_max + 1) -# define X32_NR_syscalls (__NR_x32_syscall_max + 1) -# define IA32_NR_syscalls (__NR_ia32_syscall_max + 1) +# define NR_syscalls (__NR_syscalls) # define __ARCH_WANT_NEW_STAT # define __ARCH_WANT_OLD_READDIR diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index a1b756c49a93..6cf697574661 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1773,10 +1773,16 @@ void syscall_init(void) wrmsrl_safe(MSR_IA32_SYSENTER_EIP, 0ULL); #endif - /* Flags to clear on syscall */ + /* + * Flags to clear on syscall; clear as much as possible + * to minimize user space-kernel interference. + */ wrmsrl(MSR_SYSCALL_MASK, - X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF| - X86_EFLAGS_IOPL|X86_EFLAGS_AC|X86_EFLAGS_NT); + X86_EFLAGS_CF|X86_EFLAGS_PF|X86_EFLAGS_AF| + X86_EFLAGS_ZF|X86_EFLAGS_SF|X86_EFLAGS_TF| + X86_EFLAGS_IF|X86_EFLAGS_DF|X86_EFLAGS_OF| + X86_EFLAGS_IOPL|X86_EFLAGS_NT|X86_EFLAGS_RF| + X86_EFLAGS_AC|X86_EFLAGS_ID); } #else /* CONFIG_X86_64 */ diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 04bddaaba8e2..d8b3ebd2bb85 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -62,7 +62,7 @@ SYM_CODE_START_NOALIGN(startup_64) */ /* Set up the stack for verify_cpu(), similar to initial_stack below */ - leaq (__end_init_task - SIZEOF_PTREGS)(%rip), %rsp + leaq (__end_init_task - FRAME_SIZE)(%rip), %rsp leaq _text(%rip), %rdi pushq %rsi @@ -343,10 +343,10 @@ SYM_DATA(initial_vc_handler, .quad handle_vc_boot_ghcb) #endif /* - * The SIZEOF_PTREGS gap is a convention which helps the in-kernel unwinder + * The FRAME_SIZE gap is a convention which helps the in-kernel unwinder * reliably detect the end of the stack. */ -SYM_DATA(initial_stack, .quad init_thread_union + THREAD_SIZE - SIZEOF_PTREGS) +SYM_DATA(initial_stack, .quad init_thread_union + THREAD_SIZE - FRAME_SIZE) __FINITDATA __INIT diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c index 87a4143aa7d7..4c208ea3bd9f 100644 --- a/arch/x86/kernel/ptrace.c +++ b/arch/x86/kernel/ptrace.c @@ -911,7 +911,7 @@ static int putreg32(struct task_struct *child, unsigned regno, u32 value) * syscall with TS_COMPAT still set. */ regs->orig_ax = value; - if (syscall_get_nr(child, regs) >= 0) + if (syscall_get_nr(child, regs) != -1) child->thread_info.status |= TS_I386_REGS_POKED; break; diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index a06cb107c0e8..e12779a2714d 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -713,7 +713,7 @@ handle_signal(struct ksignal *ksig, struct pt_regs *regs) save_v86_state((struct kernel_vm86_regs *) regs, VM86_SIGNAL); /* Are we from a system call? */ - if (syscall_get_nr(current, regs) >= 0) { + if (syscall_get_nr(current, regs) != -1) { /* If so, check system call restarting.. */ switch (syscall_get_error(current, regs)) { case -ERESTART_RESTARTBLOCK: @@ -793,7 +793,7 @@ void arch_do_signal_or_restart(struct pt_regs *regs, bool has_signal) } /* Did we come from a system call? */ - if (syscall_get_nr(current, regs) >= 0) { + if (syscall_get_nr(current, regs) != -1) { /* Restart the system call - no handlers present */ switch (syscall_get_error(current, regs)) { case -ERESTARTNOHAND: diff --git a/arch/x86/um/sys_call_table_32.c b/arch/x86/um/sys_call_table_32.c index 2ed81e581755..0575decb5e54 100644 --- a/arch/x86/um/sys_call_table_32.c +++ b/arch/x86/um/sys_call_table_32.c @@ -7,7 +7,6 @@ #include <linux/linkage.h> #include <linux/sys.h> #include <linux/cache.h> -#include <asm/unistd.h> #include <asm/syscall.h> #define __NO_STUBS @@ -26,20 +25,17 @@ #define old_mmap sys_old_mmap -#define __SYSCALL_I386(nr, sym) extern asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long) ; +#define __SYSCALL_WITH_COMPAT(nr, native, compat) __SYSCALL(nr, native) + +#define __SYSCALL(nr, sym) extern asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long); #include <asm/syscalls_32.h> -#undef __SYSCALL_I386 -#define __SYSCALL_I386(nr, sym) [ nr ] = sym, +#undef __SYSCALL +#define __SYSCALL(nr, sym) sym, extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long); const sys_call_ptr_t sys_call_table[] ____cacheline_aligned = { - /* - * Smells like a compiler bug -- it doesn't work - * when the & below is removed. - */ - [0 ... __NR_syscall_max] = &sys_ni_syscall, #include <asm/syscalls_32.h> }; diff --git a/arch/x86/um/sys_call_table_64.c b/arch/x86/um/sys_call_table_64.c index 2e8544dafbb0..95725b5a41ac 100644 --- a/arch/x86/um/sys_call_table_64.c +++ b/arch/x86/um/sys_call_table_64.c @@ -7,7 +7,6 @@ #include <linux/linkage.h> #include <linux/sys.h> #include <linux/cache.h> -#include <asm/unistd.h> #include <asm/syscall.h> #define __NO_STUBS @@ -36,23 +35,15 @@ #define stub_execveat sys_execveat #define stub_rt_sigreturn sys_rt_sigreturn -#define __SYSCALL_X32(nr, sym) -#define __SYSCALL_COMMON(nr, sym) __SYSCALL_64(nr, sym) - -#define __SYSCALL_64(nr, sym) extern asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long) ; +#define __SYSCALL(nr, sym) extern asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long); #include <asm/syscalls_64.h> -#undef __SYSCALL_64 -#define __SYSCALL_64(nr, sym) [ nr ] = sym, +#undef __SYSCALL +#define __SYSCALL(nr, sym) sym, extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long); const sys_call_ptr_t sys_call_table[] ____cacheline_aligned = { - /* - * Smells like a compiler bug -- it doesn't work - * when the & below is removed. - */ - [0 ... __NR_syscall_max] = &sys_ni_syscall, #include <asm/syscalls_64.h> }; diff --git a/tools/arch/x86/include/asm/asm.h b/tools/arch/x86/include/asm/asm.h new file mode 100644 index 000000000000..3ad3da9a7d97 --- /dev/null +++ b/tools/arch/x86/include/asm/asm.h @@ -0,0 +1,193 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_X86_ASM_H +#define _ASM_X86_ASM_H + +#ifdef __ASSEMBLY__ +# define __ASM_FORM(x, ...) x,## __VA_ARGS__ +# define __ASM_FORM_RAW(x, ...) x,## __VA_ARGS__ +# define __ASM_FORM_COMMA(x, ...) x,## __VA_ARGS__, +#else +#include <linux/stringify.h> +# define __ASM_FORM(x, ...) " " __stringify(x,##__VA_ARGS__) " " +# define __ASM_FORM_RAW(x, ...) __stringify(x,##__VA_ARGS__) +# define __ASM_FORM_COMMA(x, ...) " " __stringify(x,##__VA_ARGS__) "," +#endif + +#define _ASM_BYTES(x, ...) __ASM_FORM(.byte x,##__VA_ARGS__ ;) + +#ifndef __x86_64__ +/* 32 bit */ +# define __ASM_SEL(a,b) __ASM_FORM(a) +# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(a) +#else +/* 64 bit */ +# define __ASM_SEL(a,b) __ASM_FORM(b) +# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(b) +#endif + +#define __ASM_SIZE(inst, ...) __ASM_SEL(inst##l##__VA_ARGS__, \ + inst##q##__VA_ARGS__) +#define __ASM_REG(reg) __ASM_SEL_RAW(e##reg, r##reg) + +#define _ASM_PTR __ASM_SEL(.long, .quad) +#define _ASM_ALIGN __ASM_SEL(.balign 4, .balign 8) + +#define _ASM_MOV __ASM_SIZE(mov) +#define _ASM_INC __ASM_SIZE(inc) +#define _ASM_DEC __ASM_SIZE(dec) +#define _ASM_ADD __ASM_SIZE(add) +#define _ASM_SUB __ASM_SIZE(sub) +#define _ASM_XADD __ASM_SIZE(xadd) +#define _ASM_MUL __ASM_SIZE(mul) + +#define _ASM_AX __ASM_REG(ax) +#define _ASM_BX __ASM_REG(bx) +#define _ASM_CX __ASM_REG(cx) +#define _ASM_DX __ASM_REG(dx) +#define _ASM_SP __ASM_REG(sp) +#define _ASM_BP __ASM_REG(bp) +#define _ASM_SI __ASM_REG(si) +#define _ASM_DI __ASM_REG(di) + +#ifndef __x86_64__ +/* 32 bit */ + +#define _ASM_ARG1 _ASM_AX +#define _ASM_ARG2 _ASM_DX +#define _ASM_ARG3 _ASM_CX + +#define _ASM_ARG1L eax +#define _ASM_ARG2L edx +#define _ASM_ARG3L ecx + +#define _ASM_ARG1W ax +#define _ASM_ARG2W dx +#define _ASM_ARG3W cx + +#define _ASM_ARG1B al +#define _ASM_ARG2B dl +#define _ASM_ARG3B cl + +#else +/* 64 bit */ + +#define _ASM_ARG1 _ASM_DI +#define _ASM_ARG2 _ASM_SI +#define _ASM_ARG3 _ASM_DX +#define _ASM_ARG4 _ASM_CX +#define _ASM_ARG5 r8 +#define _ASM_ARG6 r9 + +#define _ASM_ARG1Q rdi +#define _ASM_ARG2Q rsi +#define _ASM_ARG3Q rdx +#define _ASM_ARG4Q rcx +#define _ASM_ARG5Q r8 +#define _ASM_ARG6Q r9 + +#define _ASM_ARG1L edi +#define _ASM_ARG2L esi +#define _ASM_ARG3L edx +#define _ASM_ARG4L ecx +#define _ASM_ARG5L r8d +#define _ASM_ARG6L r9d + +#define _ASM_ARG1W di +#define _ASM_ARG2W si +#define _ASM_ARG3W dx +#define _ASM_ARG4W cx +#define _ASM_ARG5W r8w +#define _ASM_ARG6W r9w + +#define _ASM_ARG1B dil +#define _ASM_ARG2B sil +#define _ASM_ARG3B dl +#define _ASM_ARG4B cl +#define _ASM_ARG5B r8b +#define _ASM_ARG6B r9b + +#endif + +/* + * Macros to generate condition code outputs from inline assembly, + * The output operand must be type "bool". + */ +#ifdef __GCC_ASM_FLAG_OUTPUTS__ +# define CC_SET(c) "\n\t/* output condition code " #c "*/\n" +# define CC_OUT(c) "=@cc" #c +#else +# define CC_SET(c) "\n\tset" #c " %[_cc_" #c "]\n" +# define CC_OUT(c) [_cc_ ## c] "=qm" +#endif + +#ifdef __KERNEL__ + +/* Exception table entry */ +#ifdef __ASSEMBLY__ +# define _ASM_EXTABLE_HANDLE(from, to, handler) \ + .pushsection "__ex_table","a" ; \ + .balign 4 ; \ + .long (from) - . ; \ + .long (to) - . ; \ + .long (handler) - . ; \ + .popsection + +# define _ASM_EXTABLE(from, to) \ + _ASM_EXTABLE_HANDLE(from, to, ex_handler_default) + +# define _ASM_EXTABLE_UA(from, to) \ + _ASM_EXTABLE_HANDLE(from, to, ex_handler_uaccess) + +# define _ASM_EXTABLE_CPY(from, to) \ + _ASM_EXTABLE_HANDLE(from, to, ex_handler_copy) + +# define _ASM_EXTABLE_FAULT(from, to) \ + _ASM_EXTABLE_HANDLE(from, to, ex_handler_fault) + +# ifdef CONFIG_KPROBES +# define _ASM_NOKPROBE(entry) \ + .pushsection "_kprobe_blacklist","aw" ; \ + _ASM_ALIGN ; \ + _ASM_PTR (entry); \ + .popsection +# else +# define _ASM_NOKPROBE(entry) +# endif + +#else /* ! __ASSEMBLY__ */ +# define _EXPAND_EXTABLE_HANDLE(x) #x +# define _ASM_EXTABLE_HANDLE(from, to, handler) \ + " .pushsection \"__ex_table\",\"a\"\n" \ + " .balign 4\n" \ + " .long (" #from ") - .\n" \ + " .long (" #to ") - .\n" \ + " .long (" _EXPAND_EXTABLE_HANDLE(handler) ") - .\n" \ + " .popsection\n" + +# define _ASM_EXTABLE(from, to) \ + _ASM_EXTABLE_HANDLE(from, to, ex_handler_default) + +# define _ASM_EXTABLE_UA(from, to) \ + _ASM_EXTABLE_HANDLE(from, to, ex_handler_uaccess) + +# define _ASM_EXTABLE_CPY(from, to) \ + _ASM_EXTABLE_HANDLE(from, to, ex_handler_copy) + +# define _ASM_EXTABLE_FAULT(from, to) \ + _ASM_EXTABLE_HANDLE(from, to, ex_handler_fault) + +/* For C file, we already have NOKPROBE_SYMBOL macro */ + +/* + * This output constraint should be used for any inline asm which has a "call" + * instruction. Otherwise the asm may be inserted before the frame pointer + * gets set up by the containing function. If you forget to do this, objtool + * may print a "call without frame pointer save/setup" warning. + */ +register unsigned long current_stack_pointer asm(_ASM_SP); +#define ASM_CALL_CONSTRAINT "+r" (current_stack_pointer) +#endif /* __ASSEMBLY__ */ + +#endif /* __KERNEL__ */ + +#endif /* _ASM_X86_ASM_H */ diff --git a/tools/arch/x86/include/asm/nops.h b/tools/arch/x86/include/asm/nops.h index c1e5e818ba16..c5573eaa5bb9 100644 --- a/tools/arch/x86/include/asm/nops.h +++ b/tools/arch/x86/include/asm/nops.h @@ -2,6 +2,8 @@ #ifndef _ASM_X86_NOPS_H #define _ASM_X86_NOPS_H +#include <asm/asm.h> + /* * Define nops for use with alternative() and for tracing. */ @@ -57,20 +59,14 @@ #endif /* CONFIG_64BIT */ -#ifdef __ASSEMBLY__ -#define _ASM_MK_NOP(x) .byte x -#else -#define _ASM_MK_NOP(x) ".byte " __stringify(x) "\n" -#endif - -#define ASM_NOP1 _ASM_MK_NOP(BYTES_NOP1) -#define ASM_NOP2 _ASM_MK_NOP(BYTES_NOP2) -#define ASM_NOP3 _ASM_MK_NOP(BYTES_NOP3) -#define ASM_NOP4 _ASM_MK_NOP(BYTES_NOP4) -#define ASM_NOP5 _ASM_MK_NOP(BYTES_NOP5) -#define ASM_NOP6 _ASM_MK_NOP(BYTES_NOP6) -#define ASM_NOP7 _ASM_MK_NOP(BYTES_NOP7) -#define ASM_NOP8 _ASM_MK_NOP(BYTES_NOP8) +#define ASM_NOP1 _ASM_BYTES(BYTES_NOP1) +#define ASM_NOP2 _ASM_BYTES(BYTES_NOP2) +#define ASM_NOP3 _ASM_BYTES(BYTES_NOP3) +#define ASM_NOP4 _ASM_BYTES(BYTES_NOP4) +#define ASM_NOP5 _ASM_BYTES(BYTES_NOP5) +#define ASM_NOP6 _ASM_BYTES(BYTES_NOP6) +#define ASM_NOP7 _ASM_BYTES(BYTES_NOP7) +#define ASM_NOP8 _ASM_BYTES(BYTES_NOP8) #define ASM_NOP_MAX 8 diff --git a/tools/testing/selftests/x86/syscall_numbering.c b/tools/testing/selftests/x86/syscall_numbering.c index d6b09cb1aa2c..991591718bb0 100644 --- a/tools/testing/selftests/x86/syscall_numbering.c +++ b/tools/testing/selftests/x86/syscall_numbering.c @@ -1,6 +1,8 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* - * syscall_arg_fault.c - tests faults 32-bit fast syscall stack args + * syscall_numbering.c - test calling the x86-64 kernel with various + * valid and invalid system call numbers. + * * Copyright (c) 2018 Andrew Lutomirski */ @@ -11,79 +13,470 @@ #include <stdbool.h> #include <errno.h> #include <unistd.h> -#include <syscall.h> +#include <string.h> +#include <fcntl.h> +#include <limits.h> +#include <signal.h> +#include <sysexits.h> -static int nerrs; +#include <sys/ptrace.h> +#include <sys/user.h> +#include <sys/wait.h> +#include <sys/mman.h> -#define X32_BIT 0x40000000UL +#include <linux/ptrace.h> -static void check_enosys(unsigned long nr, bool *ok) +/* Common system call numbers */ +#define SYS_READ 0 +#define SYS_WRITE 1 +#define SYS_GETPID 39 +/* x64-only system call numbers */ +#define X64_IOCTL 16 +#define X64_READV 19 +#define X64_WRITEV 20 +/* x32-only system call numbers (without X32_BIT) */ +#define X32_IOCTL 514 +#define X32_READV 515 +#define X32_WRITEV 516 + +#define X32_BIT 0x40000000 + +static int nullfd = -1; /* File descriptor for /dev/null */ +static bool with_x32; /* x32 supported on this kernel? */ + +enum ptrace_pass { + PTP_NOTHING, + PTP_GETREGS, + PTP_WRITEBACK, + PTP_FUZZRET, + PTP_FUZZHIGH, + PTP_INTNUM, + PTP_DONE +}; + +static const char * const ptrace_pass_name[] = { - /* If this fails, a segfault is reasonably likely. */ - fflush(stdout); + [PTP_NOTHING] = "just stop, no data read", + [PTP_GETREGS] = "only getregs", + [PTP_WRITEBACK] = "getregs, unmodified setregs", + [PTP_FUZZRET] = "modifying the default return", + [PTP_FUZZHIGH] = "clobbering the top 32 bits", + [PTP_INTNUM] = "sign-extending the syscall number", +}; - long ret = syscall(nr, 0, 0, 0, 0, 0, 0); - if (ret == 0) { - printf("[FAIL]\tsyscall %lu succeeded, but it should have failed\n", nr); - *ok = false; - } else if (errno != ENOSYS) { - printf("[FAIL]\tsyscall %lu had error code %d, but it should have reported ENOSYS\n", nr, errno); - *ok = false; - } +/* + * Shared memory block between tracer and test + */ +struct shared { + unsigned int nerr; /* Total error count */ + unsigned int indent; /* Message indentation level */ + enum ptrace_pass ptrace_pass; + bool probing_syscall; /* In probe_syscall() */ +}; +static volatile struct shared *sh; + +static inline unsigned int offset(void) +{ + unsigned int level = sh ? sh->indent : 0; + + return 8 + level * 4; } -static void test_x32_without_x32_bit(void) +#define msg(lvl, fmt, ...) printf("%-*s" fmt, offset(), "[" #lvl "]", \ + ## __VA_ARGS__) + +#define run(fmt, ...) msg(RUN, fmt, ## __VA_ARGS__) +#define info(fmt, ...) msg(INFO, fmt, ## __VA_ARGS__) +#define ok(fmt, ...) msg(OK, fmt, ## __VA_ARGS__) + +#define fail(fmt, ...) \ + do { \ + msg(FAIL, fmt, ## __VA_ARGS__); \ + sh->nerr++; \ + } while (0) + +#define crit(fmt, ...) \ + do { \ + sh->indent = 0; \ + msg(FAIL, fmt, ## __VA_ARGS__); \ + msg(SKIP, "Unable to run test\n"); \ + exit(EX_OSERR); \ + } while (0) + +/* Sentinel for ptrace-modified return value */ +#define MODIFIED_BY_PTRACE -9999 + +/* + * Directly invokes the given syscall with nullfd as the first argument + * and the rest zero. Avoids involving glibc wrappers in case they ever + * end up intercepting some system calls for some reason, or modify + * the system call number itself. + */ +static long long probe_syscall(int msb, int lsb) { - bool ok = true; + register long long arg1 asm("rdi") = nullfd; + register long long arg2 asm("rsi") = 0; + register long long arg3 asm("rdx") = 0; + register long long arg4 asm("r10") = 0; + register long long arg5 asm("r8") = 0; + register long long arg6 asm("r9") = 0; + long long nr = ((long long)msb << 32) | (unsigned int)lsb; + long long ret; /* - * Syscalls 512-547 are "x32" syscalls. They are intended to be - * called with the x32 (0x40000000) bit set. Calling them without - * the x32 bit set is nonsense and should not work. + * We pass in an extra copy of the extended system call number + * in %rbx, so we can examine it from the ptrace handler without + * worrying about it being possibly modified. This is to test + * the validity of struct user regs.orig_rax a.k.a. + * struct pt_regs.orig_ax. */ - printf("[RUN]\tChecking syscalls 512-547\n"); - for (int i = 512; i <= 547; i++) - check_enosys(i, &ok); + sh->probing_syscall = true; + asm volatile("syscall" + : "=a" (ret) + : "a" (nr), "b" (nr), + "r" (arg1), "r" (arg2), "r" (arg3), + "r" (arg4), "r" (arg5), "r" (arg6) + : "rcx", "r11", "memory", "cc"); + sh->probing_syscall = false; + + return ret; +} + +static const char *syscall_str(int msb, int start, int end) +{ + static char buf[64]; + const char * const type = (start & X32_BIT) ? "x32" : "x64"; + int lsb = start; /* - * Check that a handful of 64-bit-only syscalls are rejected if the x32 - * bit is set. + * Improve readability by stripping the x32 bit, but round + * toward zero so we don't display -1 as -1073741825. */ - printf("[RUN]\tChecking some 64-bit syscalls in x32 range\n"); - check_enosys(16 | X32_BIT, &ok); /* ioctl */ - check_enosys(19 | X32_BIT, &ok); /* readv */ - check_enosys(20 | X32_BIT, &ok); /* writev */ + if (lsb < 0) + lsb |= X32_BIT; + else + lsb &= ~X32_BIT; + + if (start == end) + snprintf(buf, sizeof buf, "%s syscall %d:%d", + type, msb, lsb); + else + snprintf(buf, sizeof buf, "%s syscalls %d:%d..%d", + type, msb, lsb, lsb + (end-start)); + + return buf; +} + +static unsigned int _check_for(int msb, int start, int end, long long expect, + const char *expect_str) +{ + unsigned int err = 0; + + sh->indent++; + if (start != end) + sh->indent++; + + for (int nr = start; nr <= end; nr++) { + long long ret = probe_syscall(msb, nr); + + if (ret != expect) { + fail("%s returned %lld, but it should have returned %s\n", + syscall_str(msb, nr, nr), + ret, expect_str); + err++; + } + } + + if (start != end) + sh->indent--; + + if (err) { + if (start != end) + fail("%s had %u failure%s\n", + syscall_str(msb, start, end), + err, err == 1 ? "s" : ""); + } else { + ok("%s returned %s as expected\n", + syscall_str(msb, start, end), expect_str); + } + + sh->indent--; + + return err; +} + +#define check_for(msb,start,end,expect) \ + _check_for(msb,start,end,expect,#expect) + +static bool check_zero(int msb, int nr) +{ + return check_for(msb, nr, nr, 0); +} + +static bool check_enosys(int msb, int nr) +{ + return check_for(msb, nr, nr, -ENOSYS); +} + +/* + * Anyone diagnosing a failure will want to know whether the kernel + * supports x32. Tell them. This can also be used to conditionalize + * tests based on existence or nonexistence of x32. + */ +static bool test_x32(void) +{ + long long ret; + pid_t mypid = getpid(); + + run("Checking for x32 by calling x32 getpid()\n"); + ret = probe_syscall(0, SYS_GETPID | X32_BIT); + + sh->indent++; + if (ret == mypid) { + info("x32 is supported\n"); + with_x32 = true; + } else if (ret == -ENOSYS) { + info("x32 is not supported\n"); + with_x32 = false; + } else { + fail("x32 getpid() returned %lld, but it should have returned either %lld or -ENOSYS\n", ret, (long long)mypid); + with_x32 = false; + } + sh->indent--; + return with_x32; +} + +static void test_syscalls_common(int msb) +{ + enum ptrace_pass pass = sh->ptrace_pass; + + run("Checking some common syscalls as 64 bit\n"); + check_zero(msb, SYS_READ); + check_zero(msb, SYS_WRITE); + + run("Checking some 64-bit only syscalls as 64 bit\n"); + check_zero(msb, X64_READV); + check_zero(msb, X64_WRITEV); + + run("Checking out of range system calls\n"); + check_for(msb, -64, -2, -ENOSYS); + if (pass >= PTP_FUZZRET) + check_for(msb, -1, -1, MODIFIED_BY_PTRACE); + else + check_for(msb, -1, -1, -ENOSYS); + check_for(msb, X32_BIT-64, X32_BIT-1, -ENOSYS); + check_for(msb, -64-X32_BIT, -1-X32_BIT, -ENOSYS); + check_for(msb, INT_MAX-64, INT_MAX-1, -ENOSYS); +} +static void test_syscalls_with_x32(int msb) +{ /* - * Check some syscalls with high bits set. + * Syscalls 512-547 are "x32" syscalls. They are + * intended to be called with the x32 (0x40000000) bit + * set. Calling them without the x32 bit set is + * nonsense and should not work. */ - printf("[RUN]\tChecking numbers above 2^32-1\n"); - check_enosys((1UL << 32), &ok); - check_enosys(X32_BIT | (1UL << 32), &ok); + run("Checking x32 syscalls as 64 bit\n"); + check_for(msb, 512, 547, -ENOSYS); - if (!ok) - nerrs++; - else - printf("[OK]\tThey all returned -ENOSYS\n"); + run("Checking some common syscalls as x32\n"); + check_zero(msb, SYS_READ | X32_BIT); + check_zero(msb, SYS_WRITE | X32_BIT); + + run("Checking some x32 syscalls as x32\n"); + check_zero(msb, X32_READV | X32_BIT); + check_zero(msb, X32_WRITEV | X32_BIT); + + run("Checking some 64-bit syscalls as x32\n"); + check_enosys(msb, X64_IOCTL | X32_BIT); + check_enosys(msb, X64_READV | X32_BIT); + check_enosys(msb, X64_WRITEV | X32_BIT); } -int main() +static void test_syscalls_without_x32(int msb) { + run("Checking for absence of x32 system calls\n"); + check_for(msb, 0 | X32_BIT, 999 | X32_BIT, -ENOSYS); +} + +static void test_syscall_numbering(void) +{ + static const int msbs[] = { + 0, 1, -1, X32_BIT-1, X32_BIT, X32_BIT-1, -X32_BIT, INT_MAX, + INT_MIN, INT_MIN+1 + }; + + sh->indent++; + /* - * Anyone diagnosing a failure will want to know whether the kernel - * supports x32. Tell them. + * The MSB is supposed to be ignored, so we loop over a few + * to test that out. */ - printf("\tChecking for x32..."); - fflush(stdout); - if (syscall(39 | X32_BIT, 0, 0, 0, 0, 0, 0) >= 0) { - printf(" supported\n"); - } else if (errno == ENOSYS) { - printf(" not supported\n"); + for (size_t i = 0; i < sizeof(msbs)/sizeof(msbs[0]); i++) { + int msb = msbs[i]; + run("Checking system calls with msb = %d (0x%x)\n", + msb, msb); + + sh->indent++; + + test_syscalls_common(msb); + if (with_x32) + test_syscalls_with_x32(msb); + else + test_syscalls_without_x32(msb); + + sh->indent--; + } + + sh->indent--; +} + +static void syscall_numbering_tracee(void) +{ + enum ptrace_pass pass; + + if (ptrace(PTRACE_TRACEME, 0, 0, 0)) { + crit("Failed to request tracing\n"); + return; + } + raise(SIGSTOP); + + for (sh->ptrace_pass = pass = PTP_NOTHING; pass < PTP_DONE; + sh->ptrace_pass = ++pass) { + run("Running tests under ptrace: %s\n", ptrace_pass_name[pass]); + test_syscall_numbering(); + } +} + +static void mess_with_syscall(pid_t testpid, enum ptrace_pass pass) +{ + struct user_regs_struct regs; + + sh->probing_syscall = false; /* Do this on entry only */ + + /* For these, don't even getregs */ + if (pass == PTP_NOTHING || pass == PTP_DONE) + return; + + ptrace(PTRACE_GETREGS, testpid, NULL, ®s); + + if (regs.orig_rax != regs.rbx) { + fail("orig_rax %#llx doesn't match syscall number %#llx\n", + (unsigned long long)regs.orig_rax, + (unsigned long long)regs.rbx); + } + + switch (pass) { + case PTP_GETREGS: + /* Just read, no writeback */ + return; + case PTP_WRITEBACK: + /* Write back the same register state verbatim */ + break; + case PTP_FUZZRET: + regs.rax = MODIFIED_BY_PTRACE; + break; + case PTP_FUZZHIGH: + regs.rax = MODIFIED_BY_PTRACE; + regs.orig_rax = regs.orig_rax | 0xffffffff00000000ULL; + break; + case PTP_INTNUM: + regs.rax = MODIFIED_BY_PTRACE; + regs.orig_rax = (int)regs.orig_rax; + break; + default: + crit("invalid ptrace_pass\n"); + break; + } + + ptrace(PTRACE_SETREGS, testpid, NULL, ®s); +} + +static void syscall_numbering_tracer(pid_t testpid) +{ + int wstatus; + + do { + pid_t wpid = waitpid(testpid, &wstatus, 0); + if (wpid < 0 && errno != EINTR) + break; + if (wpid != testpid) + continue; + if (!WIFSTOPPED(wstatus)) + break; /* Thread exited? */ + + if (sh->probing_syscall && WSTOPSIG(wstatus) == SIGTRAP) + mess_with_syscall(testpid, sh->ptrace_pass); + } while (sh->ptrace_pass != PTP_DONE && + !ptrace(PTRACE_SYSCALL, testpid, NULL, NULL)); + + ptrace(PTRACE_DETACH, testpid, NULL, NULL); + + /* Wait for the child process to terminate */ + while (waitpid(testpid, &wstatus, 0) != testpid || !WIFEXITED(wstatus)) + /* wait some more */; +} + +static void test_traced_syscall_numbering(void) +{ + pid_t testpid; + + /* Launch the test thread; this thread continues as the tracer thread */ + testpid = fork(); + + if (testpid < 0) { + crit("Unable to launch tracer process\n"); + } else if (testpid == 0) { + syscall_numbering_tracee(); + _exit(0); } else { - printf(" confused\n"); + syscall_numbering_tracer(testpid); } +} - test_x32_without_x32_bit(); +int main(void) +{ + unsigned int nerr; - return nerrs ? 1 : 0; + /* + * It is quite likely to get a segfault on a failure, so make + * sure the message gets out by setting stdout to nonbuffered. + */ + setvbuf(stdout, NULL, _IONBF, 0); + + /* + * Harmless file descriptor to work on... + */ + nullfd = open("/dev/null", O_RDWR); + if (nullfd < 0) { + crit("Unable to open /dev/null: %s\n", strerror(errno)); + } + + /* + * Set up a block of shared memory... + */ + sh = mmap(NULL, sysconf(_SC_PAGE_SIZE), PROT_READ|PROT_WRITE, + MAP_ANONYMOUS|MAP_SHARED, 0, 0); + if (sh == MAP_FAILED) { + crit("Unable to allocated shared memory block: %s\n", + strerror(errno)); + } + + with_x32 = test_x32(); + + run("Running tests without ptrace...\n"); + test_syscall_numbering(); + + test_traced_syscall_numbering(); + + nerr = sh->nerr; + if (!nerr) { + ok("All system calls succeeded or failed as expected\n"); + return 0; + } else { + fail("A total of %u system call%s had incorrect behavior\n", + nerr, nerr != 1 ? "s" : ""); + return 1; + } }
| |