diff options
Diffstat (limited to 'arch/x86/entry')
| -rw-r--r-- | arch/x86/entry/Makefile | 2 | ||||
| -rw-r--r-- | arch/x86/entry/common.c | 65 | ||||
| -rw-r--r-- | arch/x86/entry/entry_64_compat.S | 1 | ||||
| -rw-r--r-- | arch/x86/entry/entry_fred.c | 12 | ||||
| -rw-r--r-- | arch/x86/entry/syscalls/syscall_32.tbl | 1 | ||||
| -rw-r--r-- | arch/x86/entry/syscalls/syscall_64.tbl | 3 | ||||
| -rw-r--r-- | arch/x86/entry/thunk.S (renamed from arch/x86/entry/thunk_64.S) | 0 | ||||
| -rw-r--r-- | arch/x86/entry/thunk_32.S | 18 | ||||
| -rw-r--r-- | arch/x86/entry/vdso/Makefile | 28 | ||||
| -rw-r--r-- | arch/x86/entry/vsyscall/vsyscall_64.c | 28 |
10 files changed, 79 insertions, 79 deletions
diff --git a/arch/x86/entry/Makefile b/arch/x86/entry/Makefile index c93e7f5c2a06..ce1cc1622385 100644 --- a/arch/x86/entry/Makefile +++ b/arch/x86/entry/Makefile @@ -17,7 +17,7 @@ obj-y += common.o obj-y += vdso/ obj-y += vsyscall/ -obj-$(CONFIG_PREEMPTION) += thunk_$(BITS).o +obj-$(CONFIG_PREEMPTION) += thunk.o CFLAGS_entry_fred.o += -fno-stack-protector CFLAGS_REMOVE_entry_fred.o += -pg $(CC_FLAGS_FTRACE) obj-$(CONFIG_X86_FRED) += entry_64_fred.o entry_fred.o diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index 6de50b80702e..51cc9c7cb9bd 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -255,6 +255,71 @@ __visible noinstr void do_int80_emulation(struct pt_regs *regs) instrumentation_end(); syscall_exit_to_user_mode(regs); } + +#ifdef CONFIG_X86_FRED +/* + * A FRED-specific INT80 handler is warranted for the follwing reasons: + * + * 1) As INT instructions and hardware interrupts are separate event + * types, FRED does not preclude the use of vector 0x80 for external + * interrupts. As a result, the FRED setup code does not reserve + * vector 0x80 and calling int80_is_external() is not merely + * suboptimal but actively incorrect: it could cause a system call + * to be incorrectly ignored. + * + * 2) It is called only for handling vector 0x80 of event type + * EVENT_TYPE_SWINT and will never be called to handle any external + * interrupt (event type EVENT_TYPE_EXTINT). + * + * 3) FRED has separate entry flows depending on if the event came from + * user space or kernel space, and because the kernel does not use + * INT insns, the FRED kernel entry handler fred_entry_from_kernel() + * falls through to fred_bad_type() if the event type is + * EVENT_TYPE_SWINT, i.e., INT insns. So if the kernel is handling + * an INT insn, it can only be from a user level. + * + * 4) int80_emulation() does a CLEAR_BRANCH_HISTORY. While FRED will + * likely take a different approach if it is ever needed: it + * probably belongs in either fred_intx()/ fred_other() or + * asm_fred_entrypoint_user(), depending on if this ought to be done + * for all entries from userspace or only system + * calls. + * + * 5) INT $0x80 is the fast path for 32-bit system calls under FRED. + */ +DEFINE_FREDENTRY_RAW(int80_emulation) +{ + int nr; + + enter_from_user_mode(regs); + + instrumentation_begin(); + add_random_kstack_offset(); + + /* + * FRED pushed 0 into regs::orig_ax and regs::ax contains the + * syscall number. + * + * User tracing code (ptrace or signal handlers) might assume + * that the regs::orig_ax contains a 32-bit number on invoking + * a 32-bit syscall. + * + * Establish the syscall convention by saving the 32bit truncated + * syscall number in regs::orig_ax and by invalidating regs::ax. + */ + regs->orig_ax = regs->ax & GENMASK(31, 0); + regs->ax = -ENOSYS; + + nr = syscall_32_enter(regs); + + local_irq_enable(); + nr = syscall_enter_from_user_mode_work(regs, nr); + do_syscall_32_irqs_on(regs, nr); + + instrumentation_end(); + syscall_exit_to_user_mode(regs); +} +#endif #else /* CONFIG_IA32_EMULATION */ /* Handles int $0x80 on a 32bit kernel */ diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S index c779046cc3fe..11c9b8efdc4c 100644 --- a/arch/x86/entry/entry_64_compat.S +++ b/arch/x86/entry/entry_64_compat.S @@ -7,7 +7,6 @@ #include <asm/asm-offsets.h> #include <asm/current.h> #include <asm/errno.h> -#include <asm/ia32_unistd.h> #include <asm/thread_info.h> #include <asm/segment.h> #include <asm/irqflags.h> diff --git a/arch/x86/entry/entry_fred.c b/arch/x86/entry/entry_fred.c index ac120cbdaaf2..f004a4dc74c2 100644 --- a/arch/x86/entry/entry_fred.c +++ b/arch/x86/entry/entry_fred.c @@ -28,9 +28,9 @@ static noinstr void fred_bad_type(struct pt_regs *regs, unsigned long error_code if (regs->fred_cs.sl > 0) { pr_emerg("PANIC: invalid or fatal FRED event; event type %u " "vector %u error 0x%lx aux 0x%lx at %04x:%016lx\n", - regs->fred_ss.type, regs->fred_ss.vector, regs->orig_ax, + regs->fred_ss.type, regs->fred_ss.vector, error_code, fred_event_data(regs), regs->cs, regs->ip); - die("invalid or fatal FRED event", regs, regs->orig_ax); + die("invalid or fatal FRED event", regs, error_code); panic("invalid or fatal FRED event"); } else { unsigned long flags = oops_begin(); @@ -38,10 +38,10 @@ static noinstr void fred_bad_type(struct pt_regs *regs, unsigned long error_code pr_alert("BUG: invalid or fatal FRED event; event type %u " "vector %u error 0x%lx aux 0x%lx at %04x:%016lx\n", - regs->fred_ss.type, regs->fred_ss.vector, regs->orig_ax, + regs->fred_ss.type, regs->fred_ss.vector, error_code, fred_event_data(regs), regs->cs, regs->ip); - if (__die("Invalid or fatal FRED event", regs, regs->orig_ax)) + if (__die("Invalid or fatal FRED event", regs, error_code)) sig = 0; oops_end(flags, regs, sig); @@ -66,7 +66,7 @@ static noinstr void fred_intx(struct pt_regs *regs) /* INT80 */ case IA32_SYSCALL_VECTOR: if (ia32_enabled()) - return int80_emulation(regs); + return fred_int80_emulation(regs); fallthrough; #endif @@ -117,6 +117,8 @@ static idtentry_t sysvec_table[NR_SYSTEM_VECTORS] __ro_after_init = { SYSVEC(POSTED_INTR_VECTOR, kvm_posted_intr_ipi), SYSVEC(POSTED_INTR_WAKEUP_VECTOR, kvm_posted_intr_wakeup_ipi), SYSVEC(POSTED_INTR_NESTED_VECTOR, kvm_posted_intr_nested_ipi), + + SYSVEC(POSTED_MSI_NOTIFICATION_VECTOR, posted_msi_notification), }; static bool fred_setup_done __initdata; diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl index 5f8591ce7f25..7fd1f57ad3d3 100644 --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl @@ -466,3 +466,4 @@ 459 i386 lsm_get_self_attr sys_lsm_get_self_attr 460 i386 lsm_set_self_attr sys_lsm_set_self_attr 461 i386 lsm_list_modules sys_lsm_list_modules +462 i386 mseal sys_mseal diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index 7e8d46f4147f..a396f6e6ab5b 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -374,7 +374,7 @@ 450 common set_mempolicy_home_node sys_set_mempolicy_home_node 451 common cachestat sys_cachestat 452 common fchmodat2 sys_fchmodat2 -453 64 map_shadow_stack sys_map_shadow_stack +453 common map_shadow_stack sys_map_shadow_stack 454 common futex_wake sys_futex_wake 455 common futex_wait sys_futex_wait 456 common futex_requeue sys_futex_requeue @@ -383,6 +383,7 @@ 459 common lsm_get_self_attr sys_lsm_get_self_attr 460 common lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules +462 common mseal sys_mseal # # Due to a historical design error, certain syscalls are numbered differently diff --git a/arch/x86/entry/thunk_64.S b/arch/x86/entry/thunk.S index 119ebdc3d362..119ebdc3d362 100644 --- a/arch/x86/entry/thunk_64.S +++ b/arch/x86/entry/thunk.S diff --git a/arch/x86/entry/thunk_32.S b/arch/x86/entry/thunk_32.S deleted file mode 100644 index da37f42f4549..000000000000 --- a/arch/x86/entry/thunk_32.S +++ /dev/null @@ -1,18 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0-only */ -/* - * Trampoline to trace irqs off. (otherwise CALLER_ADDR1 might crash) - * Copyright 2008 by Steven Rostedt, Red Hat, Inc - * (inspired by Andi Kleen's thunk_64.S) - */ - -#include <linux/export.h> -#include <linux/linkage.h> -#include <asm/asm.h> - -#include "calling.h" - -THUNK preempt_schedule_thunk, preempt_schedule -THUNK preempt_schedule_notrace_thunk, preempt_schedule_notrace -EXPORT_SYMBOL(preempt_schedule_thunk) -EXPORT_SYMBOL(preempt_schedule_notrace_thunk) - diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile index 3d64bcc403cf..215a1b202a91 100644 --- a/arch/x86/entry/vdso/Makefile +++ b/arch/x86/entry/vdso/Makefile @@ -6,20 +6,6 @@ # Include the generic Makefile to check the built vDSO: include $(srctree)/lib/vdso/Makefile -# Sanitizer runtimes are unavailable and cannot be linked here. -KASAN_SANITIZE := n -KMSAN_SANITIZE_vclock_gettime.o := n -KMSAN_SANITIZE_vdso32/vclock_gettime.o := n -KMSAN_SANITIZE_vgetcpu.o := n -KMSAN_SANITIZE_vdso32/vgetcpu.o := n - -UBSAN_SANITIZE := n -KCSAN_SANITIZE := n -OBJECT_FILES_NON_STANDARD := y - -# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in. -KCOV_INSTRUMENT := n - # Files to link into the vDSO: vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o vobjs32-y := vdso32/note.o vdso32/system_call.o vdso32/sigreturn.o @@ -28,23 +14,12 @@ vobjs-$(CONFIG_X86_SGX) += vsgx.o # Files to link into the kernel: obj-y += vma.o extable.o -KASAN_SANITIZE_vma.o := y -UBSAN_SANITIZE_vma.o := y -KCSAN_SANITIZE_vma.o := y - -OBJECT_FILES_NON_STANDARD_vma.o := n -OBJECT_FILES_NON_STANDARD_extable.o := n # vDSO images to build: obj-$(CONFIG_X86_64) += vdso-image-64.o obj-$(CONFIG_X86_X32_ABI) += vdso-image-x32.o obj-$(CONFIG_COMPAT_32) += vdso-image-32.o vdso32-setup.o -OBJECT_FILES_NON_STANDARD_vdso-image-32.o := n -OBJECT_FILES_NON_STANDARD_vdso-image-x32.o := n -OBJECT_FILES_NON_STANDARD_vdso-image-64.o := n -OBJECT_FILES_NON_STANDARD_vdso32-setup.o := n - vobjs := $(addprefix $(obj)/, $(vobjs-y)) vobjs32 := $(addprefix $(obj)/, $(vobjs32-y)) @@ -176,11 +151,10 @@ quiet_cmd_vdso = VDSO $@ cmd_vdso = $(LD) -o $@ \ $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \ -T $(filter %.lds,$^) $(filter %.o,$^) && \ - sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@' + sh $(src)/checkundef.sh '$(NM)' '$@' VDSO_LDFLAGS = -shared --hash-style=both --build-id=sha1 \ $(call ld-option, --eh-frame-hdr) -Bsymbolic -z noexecstack -GCOV_PROFILE := n quiet_cmd_vdso_and_check = VDSO $@ cmd_vdso_and_check = $(cmd_vdso); $(cmd_vdso_check) diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c index a3c0df11d0e6..2fb7d53cf333 100644 --- a/arch/x86/entry/vsyscall/vsyscall_64.c +++ b/arch/x86/entry/vsyscall/vsyscall_64.c @@ -98,11 +98,6 @@ static int addr_to_vsyscall_nr(unsigned long addr) static bool write_ok_or_segv(unsigned long ptr, size_t size) { - /* - * XXX: if access_ok, get_user, and put_user handled - * sig_on_uaccess_err, this could go away. - */ - if (!access_ok((void __user *)ptr, size)) { struct thread_struct *thread = ¤t->thread; @@ -120,10 +115,8 @@ static bool write_ok_or_segv(unsigned long ptr, size_t size) bool emulate_vsyscall(unsigned long error_code, struct pt_regs *regs, unsigned long address) { - struct task_struct *tsk; unsigned long caller; int vsyscall_nr, syscall_nr, tmp; - int prev_sig_on_uaccess_err; long ret; unsigned long orig_dx; @@ -172,8 +165,6 @@ bool emulate_vsyscall(unsigned long error_code, goto sigsegv; } - tsk = current; - /* * Check for access_ok violations and find the syscall nr. * @@ -234,12 +225,8 @@ bool emulate_vsyscall(unsigned long error_code, goto do_ret; /* skip requested */ /* - * With a real vsyscall, page faults cause SIGSEGV. We want to - * preserve that behavior to make writing exploits harder. + * With a real vsyscall, page faults cause SIGSEGV. */ - prev_sig_on_uaccess_err = current->thread.sig_on_uaccess_err; - current->thread.sig_on_uaccess_err = 1; - ret = -EFAULT; switch (vsyscall_nr) { case 0: @@ -262,23 +249,12 @@ bool emulate_vsyscall(unsigned long error_code, break; } - current->thread.sig_on_uaccess_err = prev_sig_on_uaccess_err; - check_fault: if (ret == -EFAULT) { /* Bad news -- userspace fed a bad pointer to a vsyscall. */ warn_bad_vsyscall(KERN_INFO, regs, "vsyscall fault (exploit attempt?)"); - - /* - * If we failed to generate a signal for any reason, - * generate one here. (This should be impossible.) - */ - if (WARN_ON_ONCE(!sigismember(&tsk->pending.signal, SIGBUS) && - !sigismember(&tsk->pending.signal, SIGSEGV))) - goto sigsegv; - - return true; /* Don't emulate the ret. */ + goto sigsegv; } regs->ax = ret; |