diff options
Diffstat (limited to 'arch/arm64')
| -rw-r--r-- | arch/arm64/include/asm/asm-uaccess.h | 9 | ||||
| -rw-r--r-- | arch/arm64/include/asm/daifflags.h | 16 | ||||
| -rw-r--r-- | arch/arm64/include/asm/exception.h | 22 | ||||
| -rw-r--r-- | arch/arm64/include/asm/processor.h | 14 | ||||
| -rw-r--r-- | arch/arm64/include/asm/traps.h | 10 | ||||
| -rw-r--r-- | arch/arm64/kernel/Makefile | 6 | ||||
| -rw-r--r-- | arch/arm64/kernel/entry-common.c | 332 | ||||
| -rw-r--r-- | arch/arm64/kernel/entry.S | 275 | ||||
| -rw-r--r-- | arch/arm64/kernel/fpsimd.c | 6 | ||||
| -rw-r--r-- | arch/arm64/kernel/probes/kprobes.c | 4 | ||||
| -rw-r--r-- | arch/arm64/kernel/syscall.c | 4 | ||||
| -rw-r--r-- | arch/arm64/kernel/traps.c | 12 | ||||
| -rw-r--r-- | arch/arm64/kernel/vmlinux.lds.S | 3 | ||||
| -rw-r--r-- | arch/arm64/mm/fault.c | 62 |
14 files changed, 417 insertions, 358 deletions
diff --git a/arch/arm64/include/asm/asm-uaccess.h b/arch/arm64/include/asm/asm-uaccess.h index 5bf963830b17..a70575edae8e 100644 --- a/arch/arm64/include/asm/asm-uaccess.h +++ b/arch/arm64/include/asm/asm-uaccess.h @@ -74,13 +74,4 @@ alternative_if ARM64_ALT_PAN_NOT_UAO SET_PSTATE_PAN(0) alternative_else_nop_endif .endm - -/* - * Remove the address tag from a virtual address, if present. - */ - .macro untagged_addr, dst, addr - sbfx \dst, \addr, #0, #56 - and \dst, \dst, \addr - .endm - #endif diff --git a/arch/arm64/include/asm/daifflags.h b/arch/arm64/include/asm/daifflags.h index 063c964af705..9207cd5aa39e 100644 --- a/arch/arm64/include/asm/daifflags.h +++ b/arch/arm64/include/asm/daifflags.h @@ -9,6 +9,7 @@ #include <asm/arch_gicv3.h> #include <asm/cpufeature.h> +#include <asm/ptrace.h> #define DAIF_PROCCTX 0 #define DAIF_PROCCTX_NOIRQ PSR_I_BIT @@ -109,4 +110,19 @@ static inline void local_daif_restore(unsigned long flags) trace_hardirqs_off(); } +/* + * Called by synchronous exception handlers to restore the DAIF bits that were + * modified by taking an exception. + */ +static inline void local_daif_inherit(struct pt_regs *regs) +{ + unsigned long flags = regs->pstate & DAIF_MASK; + + /* + * We can't use local_daif_restore(regs->pstate) here as + * system_has_prio_mask_debugging() won't restore the I bit if it can + * use the pmr instead. + */ + write_sysreg(flags, daif); +} #endif diff --git a/arch/arm64/include/asm/exception.h b/arch/arm64/include/asm/exception.h index a17393ff6677..4d5f3b5f50cd 100644 --- a/arch/arm64/include/asm/exception.h +++ b/arch/arm64/include/asm/exception.h @@ -8,14 +8,15 @@ #define __ASM_EXCEPTION_H #include <asm/esr.h> +#include <asm/kprobes.h> +#include <asm/ptrace.h> #include <linux/interrupt.h> -#define __exception __attribute__((section(".exception.text"))) #ifdef CONFIG_FUNCTION_GRAPH_TRACER #define __exception_irq_entry __irq_entry #else -#define __exception_irq_entry __exception +#define __exception_irq_entry __kprobes #endif static inline u32 disr_to_esr(u64 disr) @@ -31,5 +32,22 @@ static inline u32 disr_to_esr(u64 disr) } asmlinkage void enter_from_user_mode(void); +void do_mem_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs); +void do_sp_pc_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs); +void do_undefinstr(struct pt_regs *regs); +asmlinkage void bad_mode(struct pt_regs *regs, int reason, unsigned int esr); +void do_debug_exception(unsigned long addr_if_watchpoint, unsigned int esr, + struct pt_regs *regs); +void do_fpsimd_acc(unsigned int esr, struct pt_regs *regs); +void do_sve_acc(unsigned int esr, struct pt_regs *regs); +void do_fpsimd_exc(unsigned int esr, struct pt_regs *regs); +void do_sysinstr(unsigned int esr, struct pt_regs *regs); +void do_sp_pc_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs); +void bad_el0_sync(struct pt_regs *regs, int reason, unsigned int esr); +void do_cp15instr(unsigned int esr, struct pt_regs *regs); +void el0_svc_handler(struct pt_regs *regs); +void el0_svc_compat_handler(struct pt_regs *regs); +void do_el0_ia_bp_hardening(unsigned long addr, unsigned int esr, + struct pt_regs *regs); #endif /* __ASM_EXCEPTION_H */ diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 5623685c7d13..8899d26f73ff 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -26,10 +26,12 @@ #include <linux/init.h> #include <linux/stddef.h> #include <linux/string.h> +#include <linux/thread_info.h> #include <asm/alternative.h> #include <asm/cpufeature.h> #include <asm/hw_breakpoint.h> +#include <asm/kasan.h> #include <asm/lse.h> #include <asm/pgtable-hwdef.h> #include <asm/pointer_auth.h> @@ -214,6 +216,18 @@ static inline void start_thread(struct pt_regs *regs, unsigned long pc, regs->sp = sp; } +static inline bool is_ttbr0_addr(unsigned long addr) +{ + /* entry assembly clears tags for TTBR0 addrs */ + return addr < TASK_SIZE; +} + +static inline bool is_ttbr1_addr(unsigned long addr) +{ + /* TTBR1 addresses may have a tag if KASAN_SW_TAGS is in use */ + return arch_kasan_reset_tag(addr) >= PAGE_OFFSET; +} + #ifdef CONFIG_COMPAT static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp) diff --git a/arch/arm64/include/asm/traps.h b/arch/arm64/include/asm/traps.h index 59690613ac31..cee5928e1b7d 100644 --- a/arch/arm64/include/asm/traps.h +++ b/arch/arm64/include/asm/traps.h @@ -42,16 +42,6 @@ static inline int __in_irqentry_text(unsigned long ptr) ptr < (unsigned long)&__irqentry_text_end; } -static inline int in_exception_text(unsigned long ptr) -{ - int in; - - in = ptr >= (unsigned long)&__exception_text_start && - ptr < (unsigned long)&__exception_text_end; - - return in ? : __in_irqentry_text(ptr); -} - static inline int in_entry_text(unsigned long ptr) { return ptr >= (unsigned long)&__entry_text_start && diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 478491f07b4f..fc6488660f64 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -13,9 +13,9 @@ CFLAGS_REMOVE_return_address.o = $(CC_FLAGS_FTRACE) # Object file lists. obj-y := debug-monitors.o entry.o irq.o fpsimd.o \ - entry-fpsimd.o process.o ptrace.o setup.o signal.o \ - sys.o stacktrace.o time.o traps.o io.o vdso.o \ - hyp-stub.o psci.o cpu_ops.o insn.o \ + entry-common.o entry-fpsimd.o process.o ptrace.o \ + setup.o signal.o sys.o stacktrace.o time.o traps.o \ + io.o vdso.o hyp-stub.o psci.o cpu_ops.o insn.o \ return_address.o cpuinfo.o cpu_errata.o \ cpufeature.o alternative.o cacheinfo.o \ smp.o smp_spin_table.o topology.o smccc-call.o \ diff --git a/arch/arm64/kernel/entry-common.c b/arch/arm64/kernel/entry-common.c new file mode 100644 index 000000000000..5dce5e56995a --- /dev/null +++ b/arch/arm64/kernel/entry-common.c @@ -0,0 +1,332 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Exception handling code + * + * Copyright (C) 2019 ARM Ltd. + */ + +#include <linux/context_tracking.h> +#include <linux/ptrace.h> +#include <linux/thread_info.h> + +#include <asm/cpufeature.h> +#include <asm/daifflags.h> +#include <asm/esr.h> +#include <asm/exception.h> +#include <asm/kprobes.h> +#include <asm/mmu.h> +#include <asm/sysreg.h> + +static void notrace el1_abort(struct pt_regs *regs, unsigned long esr) +{ + unsigned long far = read_sysreg(far_el1); + + local_daif_inherit(regs); + far = untagged_addr(far); + do_mem_abort(far, esr, regs); +} +NOKPROBE_SYMBOL(el1_abort); + +static void notrace el1_pc(struct pt_regs *regs, unsigned long esr) +{ + unsigned long far = read_sysreg(far_el1); + + local_daif_inherit(regs); + do_sp_pc_abort(far, esr, regs); +} +NOKPROBE_SYMBOL(el1_pc); + +static void el1_undef(struct pt_regs *regs) +{ + local_daif_inherit(regs); + do_undefinstr(regs); +} +NOKPROBE_SYMBOL(el1_undef); + +static void el1_inv(struct pt_regs *regs, unsigned long esr) +{ + local_daif_inherit(regs); + bad_mode(regs, 0, esr); +} +NOKPROBE_SYMBOL(el1_inv); + +static void notrace el1_dbg(struct pt_regs *regs, unsigned long esr) +{ + unsigned long far = read_sysreg(far_el1); + + /* + * The CPU masked interrupts, and we are leaving them masked during + * do_debug_exception(). Update PMR as if we had called + * local_mask_daif(). + */ + if (system_uses_irq_prio_masking()) + gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET); + + do_debug_exception(far, esr, regs); +} +NOKPROBE_SYMBOL(el1_dbg); + +asmlinkage void notrace el1_sync_handler(struct pt_regs *regs) +{ + unsigned long esr = read_sysreg(esr_el1); + + switch (ESR_ELx_EC(esr)) { + case ESR_ELx_EC_DABT_CUR: + case ESR_ELx_EC_IABT_CUR: + el1_abort(regs, esr); + break; + /* + * We don't handle ESR_ELx_EC_SP_ALIGN, since we will have hit a + * recursive exception when trying to push the initial pt_regs. + */ + case ESR_ELx_EC_PC_ALIGN: + el1_pc(regs, esr); + break; + case ESR_ELx_EC_SYS64: + case ESR_ELx_EC_UNKNOWN: + el1_undef(regs); + break; + case ESR_ELx_EC_BREAKPT_CUR: + case ESR_ELx_EC_SOFTSTP_CUR: + case ESR_ELx_EC_WATCHPT_CUR: + case ESR_ELx_EC_BRK64: + el1_dbg(regs, esr); + break; + default: + el1_inv(regs, esr); + }; +} +NOKPROBE_SYMBOL(el1_sync_handler); + +static void notrace el0_da(struct pt_regs *regs, unsigned long esr) +{ + unsigned long far = read_sysreg(far_el1); + + user_exit_irqoff(); + local_daif_restore(DAIF_PROCCTX); + far = untagged_addr(far); + do_mem_abort(far, esr, regs); +} +NOKPROBE_SYMBOL(el0_da); + +static void notrace el0_ia(struct pt_regs *regs, unsigned long esr) +{ + unsigned long far = read_sysreg(far_el1); + + /* + * We've taken an instruction abort from userspace and not yet + * re-enabled IRQs. If the address is a kernel address, apply + * BP hardening prior to enabling IRQs and pre-emption. + */ + if (!is_ttbr0_addr(far)) + arm64_apply_bp_hardening(); + + user_exit_irqoff(); + local_daif_restore(DAIF_PROCCTX); + do_mem_abort(far, esr, regs); +} +NOKPROBE_SYMBOL(el0_ia); + +static void notrace el0_fpsimd_acc(struct pt_regs *regs, unsigned long esr) +{ + user_exit_irqoff(); + local_daif_restore(DAIF_PROCCTX); + do_fpsimd_acc(esr, regs); +} +NOKPROBE_SYMBOL(el0_fpsimd_acc); + +static void notrace el0_sve_acc(struct pt_regs *regs, unsigned long esr) +{ + user_exit_irqoff(); + local_daif_restore(DAIF_PROCCTX); + do_sve_acc(esr, regs); +} +NOKPROBE_SYMBOL(el0_sve_acc); + +static void notrace el0_fpsimd_exc(struct pt_regs *regs, unsigned long esr) +{ + user_exit_irqoff(); + local_daif_restore(DAIF_PROCCTX); + do_fpsimd_exc(esr, regs); +} +NOKPROBE_SYMBOL(el0_fpsimd_exc); + +static void notrace el0_sys(struct pt_regs *regs, unsigned long esr) +{ + user_exit_irqoff(); + local_daif_restore(DAIF_PROCCTX); + do_sysinstr(esr, regs); +} +NOKPROBE_SYMBOL(el0_sys); + +static void notrace el0_pc(struct pt_regs *regs, unsigned long esr) +{ + unsigned long far = read_sysreg(far_el1); + + if (!is_ttbr0_addr(instruction_pointer(regs))) + arm64_apply_bp_hardening(); + + user_exit_irqoff(); + local_daif_restore(DAIF_PROCCTX); + do_sp_pc_abort(far, esr, regs); +} +NOKPROBE_SYMBOL(el0_pc); + +static void notrace el0_sp(struct pt_regs *regs, unsigned long esr) +{ + user_exit_irqoff(); + local_daif_restore(DAIF_PROCCTX_NOIRQ); + do_sp_pc_abort(regs->sp, esr, regs); +} +NOKPROBE_SYMBOL(el0_sp); + +static void notrace el0_undef(struct pt_regs *regs) +{ + user_exit_irqoff(); + local_daif_restore(DAIF_PROCCTX); + do_undefinstr(regs); +} +NOKPROBE_SYMBOL(el0_undef); + +static void notrace el0_inv(struct pt_regs *regs, unsigned long esr) +{ + user_exit_irqoff(); + local_daif_restore(DAIF_PROCCTX); + bad_el0_sync(regs, 0, esr); +} +NOKPROBE_SYMBOL(el0_inv); + +static void notrace el0_dbg(struct pt_regs *regs, unsigned long esr) +{ + /* Only watchpoints write FAR_EL1, otherwise its UNKNOWN */ + unsigned long far = read_sysreg(far_el1); + + if (system_uses_irq_prio_masking()) + gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET); + + user_exit_irqoff(); + do_debug_exception(far, esr, regs); + local_daif_restore(DAIF_PROCCTX_NOIRQ); +} +NOKPROBE_SYMBOL(el0_dbg); + +static void notrace el0_svc(struct pt_regs *regs) +{ + if (system_uses_irq_prio_masking()) + gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET); + + el0_svc_handler(regs); +} +NOKPROBE_SYMBOL(el0_svc); + +asmlinkage void notrace el0_sync_handler(struct pt_regs *regs) +{ + unsigned long esr = read_sysreg(esr_el1); + + switch (ESR_ELx_EC(esr)) { + case ESR_ELx_EC_SVC64: + el0_svc(regs); + break; + case ESR_ELx_EC_DABT_LOW: + el0_da(regs, esr); + break; + case ESR_ELx_EC_IABT_LOW: + el0_ia(regs, esr); + break; + case ESR_ELx_EC_FP_ASIMD: + el0_fpsimd_acc(regs, esr); + break; + case ESR_ELx_EC_SVE: + el0_sve_acc(regs, esr); + break; + case ESR_ELx_EC_FP_EXC64: + el0_fpsimd_exc(regs, esr); + break; + case ESR_ELx_EC_SYS64: + case ESR_ELx_EC_WFx: + el0_sys(regs, esr); + break; + case ESR_ELx_EC_SP_ALIGN: + el0_sp(regs, esr); + break; + case ESR_ELx_EC_PC_ALIGN: + el0_pc(regs, esr); + break; + case ESR_ELx_EC_UNKNOWN: + el0_undef(regs); + break; + case ESR_ELx_EC_BREAKPT_LOW: + case ESR_ELx_EC_SOFTSTP_LOW: + case ESR_ELx_EC_WATCHPT_LOW: + case ESR_ELx_EC_BRK64: + el0_dbg(regs, esr); + break; + default: + el0_inv(regs, esr); + } +} +NOKPROBE_SYMBOL(el0_sync_handler); + +#ifdef CONFIG_COMPAT +static void notrace el0_cp15(struct pt_regs *regs, unsigned long esr) +{ + user_exit_irqoff(); + local_daif_restore(DAIF_PROCCTX); + do_cp15instr(esr, regs); +} +NOKPROBE_SYMBOL(el0_cp15); + +static void notrace el0_svc_compat(struct pt_regs *regs) +{ + if (system_uses_irq_prio_masking()) + gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET); + + el0_svc_compat_handler(regs); +} +NOKPROBE_SYMBOL(el0_svc_compat); + +asmlinkage void notrace el0_sync_compat_handler(struct pt_regs *regs) +{ + unsigned long esr = read_sysreg(esr_el1); + + switch (ESR_ELx_EC(esr)) { + case ESR_ELx_EC_SVC32: + el0_svc_compat(regs); + break; + case ESR_ELx_EC_DABT_LOW: + el0_da(regs, esr); + break; + case ESR_ELx_EC_IABT_LOW: + el0_ia(regs, esr); + break; + case ESR_ELx_EC_FP_ASIMD: + el0_fpsimd_acc(regs, esr); + break; + case ESR_ELx_EC_FP_EXC32: + el0_fpsimd_exc(regs, esr); + break; + case ESR_ELx_EC_PC_ALIGN: + el0_pc(regs, esr); + break; + case ESR_ELx_EC_UNKNOWN: + case ESR_ELx_EC_CP14_MR: + case ESR_ELx_EC_CP14_LS: + case ESR_ELx_EC_CP14_64: + el0_undef(regs); + break; + case ESR_ELx_EC_CP15_32: + case ESR_ELx_EC_CP15_64: + el0_cp15(regs, esr); + break; + case ESR_ELx_EC_BREAKPT_LOW: + case ESR_ELx_EC_SOFTSTP_LOW: + case ESR_ELx_EC_WATCHPT_LOW: + case ESR_ELx_EC_BKPT32: + el0_dbg(regs, esr); + break; + default: + el0_inv(regs, esr); + } +} +NOKPROBE_SYMBOL(el0_sync_compat_handler); +#endif /* CONFIG_COMPAT */ diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index cf3bd2976e57..d440a2a51729 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -578,76 +578,9 @@ ENDPROC(el1_error_invalid) .align 6 el1_sync: kernel_entry 1 - mrs x1, esr_el1 // read the syndrome register - lsr x24, x1, #ESR_ELx_EC_SHIFT // exception class - cmp x24, #ESR_ELx_EC_DABT_CUR // data abort in EL1 - b.eq el1_da - cmp x24, #ESR_ELx_EC_IABT_CUR // instruction abort in EL1 - b.eq el1_ia - cmp x24, #ESR_ELx_EC_SYS64 // configurable trap - b.eq el1_undef - cmp x24, #ESR_ELx_EC_PC_ALIGN // pc alignment exception - b.eq el1_pc - cmp x24, #ESR_ELx_EC_UNKNOWN // unknown exception in EL1 - b.eq el1_undef - cmp x24, #ESR_ELx_EC_BREAKPT_CUR // debug exception in EL1 - b.ge el1_dbg - b el1_inv - -el1_ia: - /* - * Fall through to the Data abort case - */ -el1_da: - /* - * Data abort handling - */ - mrs x3, far_el1 - inherit_daif pstate=x23, tmp=x2 - untagged_addr x0, x3 - mov x2, sp // struct pt_regs - bl do_mem_abort - - kernel_exit 1 -el1_pc: - /* - * PC alignment exception handling. We don't handle SP alignment faults, - * since we will have hit a recursive exception when trying to push the - * initial pt_regs. - */ - mrs x0, far_el1 - inherit_daif pstate=x23, tmp=x2 - mov x2, sp - bl do_sp_pc_abort - ASM_BUG() -el1_undef: - /* - * Undefined instruction - */ - inherit_daif pstate=x23, tmp=x2 mov x0, sp - bl do_undefinstr + bl el1_sync_handler kernel_exit 1 -el1_dbg: - /* - * Debug exception handling - */ - cmp x24, #ESR_ELx_EC_BRK64 // if BRK64 - cinc x24, x24, eq // set bit '0' - tbz x24, #0, el1_inv // EL1 only - gic_prio_kentry_setup tmp=x3 - mrs x0, far_el1 - mov x2, sp // struct pt_regs - bl do_debug_exception - kernel_exit 1 -el1_inv: - // TODO: add support for undefined instructions in kernel mode - inherit_daif pstate=x23, tmp=x2 - mov x0, sp - mov x2, x1 - mov x1, #BAD_SYNC - bl bad_mode - ASM_BUG() ENDPROC(el1_sync) .align 6 @@ -714,71 +647,18 @@ ENDPROC(el1_irq) .align 6 el0_sync: kernel_entry 0 - mrs x25, esr_el1 // read the syndrome register - lsr x24, x25, #ESR_ELx_EC_SHIFT // exception class - cmp x24, #ESR_ELx_EC_SVC64 // SVC in 64-bit state - b.eq el0_svc - cmp x24, #ESR_ELx_EC_DABT_LOW // data abort in EL0 - b.eq el0_da - cmp x24, #ESR_ELx_EC_IABT_LOW // instruction abort in EL0 - b.eq el0_ia - cmp x24, #ESR_ELx_EC_FP_ASIMD // FP/ASIMD access - b.eq el0_fpsimd_acc - cmp x24, #ESR_ELx_EC_SVE // SVE access - b.eq el0_sve_acc - cmp x24, #ESR_ELx_EC_FP_EXC64 // FP/ASIMD exception - b.eq el0_fpsimd_exc - cmp x24, #ESR_ELx_EC_SYS64 // configurable trap - ccmp x24, #ESR_ELx_EC_WFx, #4, ne - b.eq el0_sys - cmp x24, #ESR_ELx_EC_SP_ALIGN // stack alignment exception - b.eq el0_sp - cmp x24, #ESR_ELx_EC_PC_ALIGN // pc alignment exception - b.eq el0_pc - cmp x24, #ESR_ELx_EC_UNKNOWN // unknown exception in EL0 - b.eq el0_undef - cmp x24, #ESR_ELx_EC_BREAKPT_LOW // debug exception in EL0 - b.ge el0_dbg - b el0_inv + mov x0, sp + bl el0_sync_handler + b ret_to_user #ifdef CONFIG_COMPAT .align 6 el0_sync_compat: kernel_entry 0, 32 - mrs x25, esr_el1 // read the syndrome register - lsr x24, x25, #ESR_ELx_EC_SHIFT // exception class - cmp x24, #ESR_ELx_EC_SVC32 // SVC in 32-bit state - b.eq el0_svc_compat - cmp x24, #ESR_ELx_EC_DABT_LOW // data abort in EL0 - b.eq el0_da - cmp x24, #ESR_ELx_EC_IABT_LOW // instruction abort in EL0 - b.eq el0_ia - cmp x24, #ESR_ELx_EC_FP_ASIMD // FP/ASIMD access - b.eq el0_fpsimd_acc - cmp x24, #ESR_ELx_EC_FP_EXC32 // FP/ASIMD exception - b.eq el0_fpsimd_exc - cmp x24, #ESR_ELx_EC_PC_ALIGN // pc alignment exception - b.eq el0_pc - cmp x24, #ESR_ELx_EC_UNKNOWN // unknown exception in EL0 - b.eq el0_undef - cmp x24, #ESR_ELx_EC_CP15_32 // CP15 MRC/MCR trap - b.eq el0_cp15 - cmp x24, #ESR_ELx_EC_CP15_64 // CP15 MRRC/MCRR trap - b.eq el0_cp15 - cmp x24, #ESR_ELx_EC_CP14_MR // CP14 MRC/MCR trap - b.eq el0_undef - cmp x24, #ESR_ELx_EC_CP14_LS // CP14 LDC/STC trap - b.eq el0_undef - cmp x24, #ESR_ELx_EC_CP14_64 // CP14 MRRC/MCRR trap - b.eq el0_undef - cmp x24, #ESR_ELx_EC_BREAKPT_LOW // debug exception in EL0 - b.ge el0_dbg - b el0_inv -el0_svc_compat: - gic_prio_kentry_setup tmp=x1 mov x0, sp - bl el0_svc_compat_handler + bl el0_sync_compat_handler b ret_to_user +ENDPROC(el0_sync) .align 6 el0_irq_compat: @@ -788,139 +668,7 @@ el0_irq_compat: el0_error_compat: kernel_entry 0, 32 b el0_error_naked - -el0_cp15: - /* - * Trapped CP15 (MRC, MCR, MRRC, MCRR) instructions - */ - ct_user_exit_irqoff - enable_daif - mov x0, x25 - mov x1, sp - bl do_cp15instr - b ret_to_user -#endif - -el0_da: - /* - * Data abort handling - */ - mrs x26, far_el1 - ct_user_exit_irqoff - enable_daif - untagged_addr x0, x26 - mov x1, x25 - mov x2, sp - bl do_mem_abort - b ret_to_user -el0_ia: - /* - * Instruction abort handling - */ - mrs x26, far_el1 - gic_prio_kentry_setup tmp=x0 - ct_user_exit_irqoff - enable_da_f -#ifdef CONFIG_TRACE_IRQFLAGS - bl trace_hardirqs_off -#endif - mov x0, x26 - mov x1, x25 - mov x2, sp - bl do_el0_ia_bp_hardening - b ret_to_user -el0_fpsimd_acc: - /* - * Floating Point or Advanced SIMD access - */ - ct_user_exit_irqoff - enable_daif - mov x0, x25 - mov x1, sp - bl do_fpsimd_acc - b ret_to_user -el0_sve_acc: - /* - * Scalable Vector Extension access - */ - ct_user_exit_irqoff - enable_daif - mov x0, x25 - mov x1, sp - bl do_sve_acc - b ret_to_user -el0_fpsimd_exc: - /* - * Floating Point, Advanced SIMD or SVE exception - */ - ct_user_exit_irqoff - enable_daif - mov x0, x25 - mov x1, sp - bl do_fpsimd_exc - b ret_to_user -el0_sp: - ldr x26, [sp, #S_SP] - b el0_sp_pc -el0_pc: - mrs x26, far_el1 -el0_sp_pc: - /* - * Stack or PC alignment exception handling - */ - gic_prio_kentry_setup tmp=x0 - ct_user_exit_irqoff - enable_da_f -#ifdef CONFIG_TRACE_IRQFLAGS - bl trace_hardirqs_off #endif - mov x0, x26 - mov x1, x25 - mov x2, sp - bl do_sp_pc_abort - b ret_to_user -el0_undef: - /* - * Undefined instruction - */ - ct_user_exit_irqoff - enable_daif - mov x0, sp - bl do_undefinstr - b ret_to_user -el0_sys: - /* - * System instructions, for trapped cache maintenance instructions - */ - ct_user_exit_irqoff - enable_daif - mov x0, x25 - mov x1, sp - bl do_sysinstr - b ret_to_user -el0_dbg: - /* - * Debug exception handling - */ - tbnz x24, #0, el0_inv // EL0 only - mrs x24, far_el1 - gic_prio_kentry_setup tmp=x3 - ct_user_exit_irqoff - mov x0, x24 - mov x1, x25 - mov x2, sp - bl do_debug_exception - enable_da_f - b ret_to_user -el0_inv: - ct_user_exit_irqoff - enable_daif - mov x0, sp - mov x1, #BAD_SYNC - mov x2, x25 - bl bad_el0_sync - b ret_to_user -ENDPROC(el0_sync) .align 6 el0_irq: @@ -999,17 +747,6 @@ finish_ret_to_user: kernel_exit 0 ENDPROC(ret_to_user) -/* - * SVC handler. - */ - .align 6 -el0_svc: - gic_prio_kentry_setup tmp=x1 - mov x0, sp - bl el0_svc_handler - b ret_to_user -ENDPROC(el0_svc) - .popsection // .entry.text #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 37d3912cfe06..3eb338f14386 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -920,7 +920,7 @@ void fpsimd_release_task(struct task_struct *dead_task) * would have disabled the SVE access trap for userspace during * ret_to_user, making an SVE access trap impossible in that case. */ -asmlinkage void do_sve_acc(unsigned int esr, struct pt_regs *regs) +void do_sve_acc(unsigned int esr, struct pt_regs *regs) { /* Even if we chose not to use SVE, the hardware could still trap: */ if (unlikely(!system_supports_sve()) || WARN_ON(is_compat_task())) { @@ -947,7 +947,7 @@ asmlinkage void do_sve_acc(unsigned int esr, struct pt_regs *regs) /* * Trapped FP/ASIMD access. */ -asmlinkage void do_fpsimd_acc(unsigned int esr, struct pt_regs *regs) +void do_fpsimd_acc(unsigned int esr, struct pt_regs *regs) { /* TODO: implement lazy context saving/restoring */ WARN_ON(1); @@ -956,7 +956,7 @@ asmlinkage void do_fpsimd_acc(unsigned int esr, struct pt_regs *regs) /* * Raise a SIGFPE for the current process. */ -asmlinkage void do_fpsimd_exc(unsigned int esr, struct pt_regs *regs) +void do_fpsimd_exc(unsigned int esr, struct pt_regs *regs) { unsigned int si_code = FPE_FLTUNK; diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c index c4452827419b..d1c95dcf1d78 100644 --- a/arch/arm64/kernel/probes/kprobes.c +++ b/arch/arm64/kernel/probes/kprobes.c @@ -455,10 +455,6 @@ int __init arch_populate_kprobe_blacklist(void) (unsigned long)__irqentry_text_end); if (ret) return ret; - ret = kprobe_add_area_blacklist((unsigned long)__exception_text_start, - (unsigned long)__exception_text_end); - if (ret) - return ret; ret = kprobe_add_area_blacklist((unsigned long)__idmap_text_start, (unsigned long)__idmap_text_end); if (ret) diff --git a/arch/arm64/kernel/syscall.c b/arch/arm64/kernel/syscall.c index 871c739f060a..9a9d98a443fc 100644 --- a/arch/arm64/kernel/syscall.c +++ b/arch/arm64/kernel/syscall.c @@ -154,14 +154,14 @@ static inline void sve_user_discard(void) sve_user_disable(); } -asmlinkage void el0_svc_handler(struct pt_regs *regs) +void el0_svc_handler(struct pt_regs *regs) { sve_user_discard(); el0_svc_common(regs, regs->regs[8], __NR_syscalls, sys_call_table); } #ifdef CONFIG_COMPAT -asmlinkage void el0_svc_compat_handler(struct pt_regs *regs) +void el0_svc_compat_handler(struct pt_regs *regs) { el0_svc_common(regs, regs->regs[7], __NR_compat_syscalls, compat_sys_call_table); diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 4e3e9d9c8151..73caf35c2262 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -35,6 +35,7 @@ #include <asm/debug-monitors.h> #include <asm/esr.h> #include <asm/insn.h> +#include <asm/kprobes.h> #include <asm/traps.h> #include <asm/smp.h> #include <asm/stack_pointer.h> @@ -393,7 +394,7 @@ void arm64_notify_segfault(unsigned long addr) force_signal_inject(SIGSEGV, code, addr); } -asmlinkage void __exception do_undefinstr(struct pt_regs *regs) +void do_undefinstr(struct pt_regs *regs) { /* check for AArch32 breakpoint instructions */ if (!aarch32_break_handler(regs)) @@ -405,6 +406,7 @@ asmlinkage void __exception do_undefinstr(struct pt_regs *regs) BUG_ON(!user_mode(regs)); force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc); } +NOKPROBE_SYMBOL(do_undefinstr); #define __user_cache_maint(insn, address, res) \ if (address >= user_addr_max()) { \ @@ -676,7 +678,7 @@ static const struct sys64_hook cp15_64_hooks[] = { {}, }; -asmlinkage void __exception do_cp15instr(unsigned int esr, struct pt_regs *regs) +void do_cp15instr(unsigned int esr, struct pt_regs *regs) { const struct sys64_hook *hook, *hook_base; @@ -714,9 +716,10 @@ asmlinkage void __exception do_cp15instr(unsigned int esr, struct pt_regs *regs) */ do_undefinstr(regs); } +NOKPROBE_SYMBOL(do_cp15instr); #endif -asmlinkage void __exception do_sysinstr(unsigned int esr, struct pt_regs *regs) +void do_sysinstr(unsigned int esr, struct pt_regs *regs) { const struct sys64_hook *hook; @@ -733,6 +736,7 @@ asmlinkage void __exception do_sysinstr(unsigned int esr, struct pt_regs *regs) */ do_undefinstr(regs); } +NOKPROBE_SYMBOL(do_sysinstr); static const char *esr_class_str[] = { [0 ... ESR_ELx_EC_MAX] = "UNRECOGNIZED EC", @@ -802,7 +806,7 @@ asmlinkage void bad_mode(struct pt_regs *regs, int reason, unsigned int esr) * bad_el0_sync handles unexpected, but potentially recoverable synchronous * exceptions taken from EL0. Unlike bad_mode, this returns. */ -asmlinkage void bad_el0_sync(struct pt_regs *regs, int reason, unsigned int esr) +void bad_el0_sync(struct pt_regs *regs, int reason, unsigned int esr) { void __user *pc = (void __user *)instruction_pointer(regs); diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S index aa76f7259668..009057517bdd 100644 --- a/arch/arm64/kernel/vmlinux.lds.S +++ b/arch/arm64/kernel/vmlinux.lds.S @@ -111,9 +111,6 @@ SECTIONS } .text : { /* Real text segment */ _stext = .; /* Text and read-only data */ - __exception_text_start = .; - *(.exception.text) - __exception_text_end = .; IRQENTRY_TEXT SOFTIRQENTRY_TEXT ENTRY_TEXT diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 9fc6db0bcbad..7ae3a5bb8a53 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -32,7 +32,8 @@ #include <asm/daifflags.h> #include <asm/debug-monitors.h> #include <asm/esr.h> -#include <asm/kasan.h> +#include <asm/kprobes.h> +#include <asm/processor.h> #include <asm/sysreg.h> #include <asm/system_misc.h> #include <asm/pgtable.h> @@ -101,18 +102,6 @@ static void mem_abort_decode(unsigned int esr) data_abort_decode(esr); } -static inline bool is_ttbr0_addr(unsigned long addr) -{ - /* entry assembly clears tags for TTBR0 addrs */ - return addr < TASK_SIZE; -} - -static inline bool is_ttbr1_addr(unsigned long addr) -{ - /* TTBR1 addresses may have a tag if KASAN_SW_TAGS is in use */ - return arch_kasan_reset_tag(addr) >= PAGE_OFFSET; -} - static inline unsigned long mm_to_pgd_phys(struct mm_struct *mm) { /* Either init_pg_dir or swapper_pg_dir */ @@ -736,8 +725,7 @@ static const struct fault_info fault_info[] = { { do_bad, SIGKILL, SI_KERNEL, "unknown 63" }, }; -asmlinkage void __exception do_mem_abort(unsigned long addr, unsigned int esr, - struct pt_regs *regs) +void do_mem_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs) { const struct fault_info *inf = esr_to_fault_info(esr); @@ -753,43 +741,21 @@ asmlinkage void __exception do_mem_abort(unsigned long addr, unsigned int esr, arm64_notify_die(inf->name, regs, inf->sig, inf->code, (void __user *)addr, esr); } +NOKPROBE_SYMBOL(do_mem_abort); -asmlinkage void __exception do_el0_irq_bp_hardening(void) +void do_el0_irq_bp_hardening(void) { /* PC has already been checked in entry.S */ arm64_apply_bp_hardening(); } +NOKPROBE_SYMBOL(do_el0_irq_bp_hardening); -asmlinkage void __exception do_el0_ia_bp_hardening(unsigned long addr, - unsigned int esr, - struct pt_regs *regs) -{ - /* - * We've taken an instruction abort from userspace and not yet - * re-enabled IRQs. If the address is a kernel address, apply - * BP hardening prior to enabling IRQs and pre-emption. - */ - if (!is_ttbr0_addr(addr)) - arm64_apply_bp_hardening(); - - local_daif_restore(DAIF_PROCCTX); - do_mem_abort(addr, esr, regs); -} - - -asmlinkage void __exception do_sp_pc_abort(unsigned long addr, - unsigned int esr, - struct pt_regs *regs) +void do_sp_pc_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs) { - if (user_mode(regs)) { - if (!is_ttbr0_addr(instruction_pointer(regs))) - arm64_apply_bp_hardening(); - local_daif_restore(DAIF_PROCCTX); - } - arm64_notify_die("SP/PC alignment exception", regs, SIGBUS, BUS_ADRALN, (void __user *)addr, esr); } +NOKPROBE_SYMBOL(do_sp_pc_abort); int __init early_brk64(unsigned long addr, unsigned int esr, struct pt_regs *regs); @@ -872,8 +838,7 @@ NOKPROBE_SYMBOL(debug_exception_exit); #ifdef CONFIG_ARM64_ERRATUM_1463225 DECLARE_PER_CPU(int, __in_cortex_a76_erratum_1463225_wa); -static int __exception -cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs) +static int cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs) { if (user_mode(regs)) return 0; @@ -892,16 +857,15 @@ cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs) return 1; } #else -static int __exception -cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs) +static int cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs) { return 0; } #endif /* CONFIG_ARM64_ERRATUM_1463225 */ +NOKPROBE_SYMBOL(cortex_a76_erratum_1463225_debug_handler); -asmlinkage void __exception do_debug_exception(unsigned long addr_if_watchpoint, - unsigned int esr, - struct pt_regs *regs) +void do_debug_exception(unsigned long addr_if_watchpoint, unsigned int esr, + struct pt_regs *regs) { const struct fault_info *inf = esr_to_debug_fault_info(esr); unsigned long pc = instruction_pointer(regs); |