diff options
| -rw-r--r-- | arch/Kconfig | 1 | ||||
| -rw-r--r-- | arch/sparc/Kconfig | 3 | ||||
| -rw-r--r-- | arch/sparc/configs/sparc64_defconfig | 1 | ||||
| -rw-r--r-- | arch/sparc/include/asm/kdebug_64.h | 2 | ||||
| -rw-r--r-- | arch/sparc/include/asm/ptrace.h | 35 | ||||
| -rw-r--r-- | arch/sparc/include/asm/thread_info_64.h | 6 | ||||
| -rw-r--r-- | arch/sparc/include/asm/ttable.h | 6 | ||||
| -rw-r--r-- | arch/sparc/include/asm/uprobes.h | 59 | ||||
| -rw-r--r-- | arch/sparc/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/sparc/kernel/ptrace_64.c | 54 | ||||
| -rw-r--r-- | arch/sparc/kernel/signal_64.c | 2 | ||||
| -rw-r--r-- | arch/sparc/kernel/ttable_64.S | 2 | ||||
| -rw-r--r-- | arch/sparc/kernel/uprobes.c | 331 | ||||
| -rw-r--r-- | include/linux/uprobes.h | 1 |
14 files changed, 500 insertions, 4 deletions
diff --git a/arch/Kconfig b/arch/Kconfig index 659bdd079277..44a44b49eb3a 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -96,6 +96,7 @@ config KPROBES_ON_FTRACE config UPROBES def_bool n + depends on ARCH_SUPPORTS_UPROBES help Uprobes is the user-space counterpart to kprobes: they enable instrumentation applications (such as 'perf probe') diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index 165ecdd24d22..cf4034c66362 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -155,6 +155,9 @@ config PGTABLE_LEVELS default 4 if 64BIT default 3 +config ARCH_SUPPORTS_UPROBES + def_bool y if SPARC64 + source "init/Kconfig" source "kernel/Kconfig.freezer" diff --git a/arch/sparc/configs/sparc64_defconfig b/arch/sparc/configs/sparc64_defconfig index 3583d676a916..b2e650d1764f 100644 --- a/arch/sparc/configs/sparc64_defconfig +++ b/arch/sparc/configs/sparc64_defconfig @@ -213,6 +213,7 @@ CONFIG_SCHEDSTATS=y # CONFIG_RCU_CPU_STALL_DETECTOR is not set CONFIG_SYSCTL_SYSCALL_CHECK=y CONFIG_BLK_DEV_IO_TRACE=y +CONFIG_UPROBE_EVENTS=y CONFIG_KEYS=y CONFIG_CRYPTO_NULL=m CONFIG_CRYPTO_TEST=m diff --git a/arch/sparc/include/asm/kdebug_64.h b/arch/sparc/include/asm/kdebug_64.h index 04465de8f3b5..867286bf7b1a 100644 --- a/arch/sparc/include/asm/kdebug_64.h +++ b/arch/sparc/include/asm/kdebug_64.h @@ -10,6 +10,8 @@ enum die_val { DIE_OOPS = 1, DIE_DEBUG, /* ta 0x70 */ DIE_DEBUG_2, /* ta 0x71 */ + DIE_BPT, /* ta 0x73 */ + DIE_SSTEP, /* ta 0x74 */ DIE_DIE, DIE_TRAP, DIE_TRAP_TL1, diff --git a/arch/sparc/include/asm/ptrace.h b/arch/sparc/include/asm/ptrace.h index bac6a946ee00..ca57f08bd3db 100644 --- a/arch/sparc/include/asm/ptrace.h +++ b/arch/sparc/include/asm/ptrace.h @@ -61,7 +61,10 @@ extern union global_cpu_snapshot global_cpu_snapshot[NR_CPUS]; #define force_successful_syscall_return() set_thread_noerror(1) #define user_mode(regs) (!((regs)->tstate & TSTATE_PRIV)) #define instruction_pointer(regs) ((regs)->tpc) -#define instruction_pointer_set(regs, val) ((regs)->tpc = (val)) +#define instruction_pointer_set(regs, val) do { \ + (regs)->tpc = (val); \ + (regs)->tnpc = (val)+4; \ + } while (0) #define user_stack_pointer(regs) ((regs)->u_regs[UREG_FP]) static inline int is_syscall_success(struct pt_regs *regs) { @@ -77,6 +80,36 @@ unsigned long profile_pc(struct pt_regs *); #else #define profile_pc(regs) instruction_pointer(regs) #endif + +#define MAX_REG_OFFSET (offsetof(struct pt_regs, magic)) + +extern int regs_query_register_offset(const char *name); + +/** + * regs_get_register() - get register value from its offset + * @regs: pt_regs from which register value is gotten + * @offset: offset number of the register. + * + * regs_get_register returns the value of a register whose + * offset from @regs. The @offset is the offset of the register + * in struct pt_regs. If @offset is bigger than MAX_REG_OFFSET, + * this returns 0. + */ +static inline unsigned long regs_get_register(struct pt_regs *regs, + unsigned long offset) +{ + if (unlikely(offset >= MAX_REG_OFFSET)) + return 0; + if (offset == PT_V9_Y) + return *(unsigned int *)((unsigned long)regs + offset); + return *(unsigned long *)((unsigned long)regs + offset); +} + +/* Valid only for Kernel mode traps. */ +static inline unsigned long kernel_stack_pointer(struct pt_regs *regs) +{ + return regs->u_regs[UREG_I6]; +} #else /* __ASSEMBLY__ */ #endif /* __ASSEMBLY__ */ #else /* (defined(__sparc__) && defined(__arch64__)) */ diff --git a/arch/sparc/include/asm/thread_info_64.h b/arch/sparc/include/asm/thread_info_64.h index 3d7b925f6516..38a24f257b85 100644 --- a/arch/sparc/include/asm/thread_info_64.h +++ b/arch/sparc/include/asm/thread_info_64.h @@ -180,7 +180,7 @@ register struct thread_info *current_thread_info_reg asm("g6"); #define TIF_NEED_RESCHED 3 /* rescheduling necessary */ /* flag bit 4 is available */ #define TIF_UNALIGNED 5 /* allowed to do unaligned accesses */ -/* flag bit 6 is available */ +#define TIF_UPROBE 6 /* breakpointed or singlestepped */ #define TIF_32BIT 7 /* 32-bit binary */ #define TIF_NOHZ 8 /* in adaptive nohz mode */ #define TIF_SECCOMP 9 /* secure computing */ @@ -199,6 +199,7 @@ register struct thread_info *current_thread_info_reg asm("g6"); #define _TIF_SIGPENDING (1<<TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED) #define _TIF_UNALIGNED (1<<TIF_UNALIGNED) +#define _TIF_UPROBE (1<<TIF_UPROBE) #define _TIF_32BIT (1<<TIF_32BIT) #define _TIF_NOHZ (1<<TIF_NOHZ) #define _TIF_SECCOMP (1<<TIF_SECCOMP) @@ -209,7 +210,8 @@ register struct thread_info *current_thread_info_reg asm("g6"); #define _TIF_USER_WORK_MASK ((0xff << TI_FLAG_WSAVED_SHIFT) | \ _TIF_DO_NOTIFY_RESUME_MASK | \ _TIF_NEED_RESCHED) -#define _TIF_DO_NOTIFY_RESUME_MASK (_TIF_NOTIFY_RESUME | _TIF_SIGPENDING) +#define _TIF_DO_NOTIFY_RESUME_MASK (_TIF_NOTIFY_RESUME | \ + _TIF_SIGPENDING | _TIF_UPROBE) #define is_32bit_task() (test_thread_flag(TIF_32BIT)) diff --git a/arch/sparc/include/asm/ttable.h b/arch/sparc/include/asm/ttable.h index 781b9f1dbdc2..82e7df296abc 100644 --- a/arch/sparc/include/asm/ttable.h +++ b/arch/sparc/include/asm/ttable.h @@ -186,6 +186,12 @@ #define KPROBES_TRAP(lvl) TRAP_ARG(bad_trap, lvl) #endif +#ifdef CONFIG_UPROBES +#define UPROBES_TRAP(lvl) TRAP_ARG(uprobe_trap, lvl) +#else +#define UPROBES_TRAP(lvl) TRAP_ARG(bad_trap, lvl) +#endif + #ifdef CONFIG_KGDB #define KGDB_TRAP(lvl) TRAP_IRQ(kgdb_trap, lvl) #else diff --git a/arch/sparc/include/asm/uprobes.h b/arch/sparc/include/asm/uprobes.h new file mode 100644 index 000000000000..f87aae5a908e --- /dev/null +++ b/arch/sparc/include/asm/uprobes.h @@ -0,0 +1,59 @@ +#ifndef _ASM_UPROBES_H +#define _ASM_UPROBES_H +/* + * User-space Probes (UProbes) for sparc + * + * Copyright (C) 2013 Oracle, Inc. + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + * Authors: + * Jose E. Marchesi <jose.marchesi@oracle.com> + * Eric Saint Etienne <eric.saint.etienne@oracle.com> + */ + +typedef u32 uprobe_opcode_t; + +#define MAX_UINSN_BYTES 4 +#define UPROBE_XOL_SLOT_BYTES (MAX_UINSN_BYTES * 2) + +#define UPROBE_SWBP_INSN_SIZE 4 +#define UPROBE_SWBP_INSN 0x91d02073 /* ta 0x73 */ +#define UPROBE_STP_INSN 0x91d02074 /* ta 0x74 */ + +#define ANNUL_BIT (1 << 29) + +struct arch_uprobe { + union { + u8 insn[MAX_UINSN_BYTES]; + u32 ixol; + }; +}; + +struct arch_uprobe_task { + u32 saved_tpc; + u32 saved_tnpc; +}; + +struct task_struct; +struct notifier_block; + +extern int arch_uprobe_analyze_insn(struct arch_uprobe *aup, struct mm_struct *mm, unsigned long addr); +extern int arch_uprobe_pre_xol(struct arch_uprobe *aup, struct pt_regs *regs); +extern int arch_uprobe_post_xol(struct arch_uprobe *aup, struct pt_regs *regs); +extern bool arch_uprobe_xol_was_trapped(struct task_struct *tsk); +extern int arch_uprobe_exception_notify(struct notifier_block *self, unsigned long val, void *data); +extern void arch_uprobe_abort_xol(struct arch_uprobe *aup, struct pt_regs *regs); + +#endif /* _ASM_UPROBES_H */ diff --git a/arch/sparc/kernel/Makefile b/arch/sparc/kernel/Makefile index fa3c02d41138..aac609889ee4 100644 --- a/arch/sparc/kernel/Makefile +++ b/arch/sparc/kernel/Makefile @@ -116,4 +116,5 @@ obj-$(CONFIG_COMPAT) += $(audit--y) pc--$(CONFIG_PERF_EVENTS) := perf_event.o obj-$(CONFIG_SPARC64) += $(pc--y) +obj-$(CONFIG_UPROBES) += uprobes.o obj-$(CONFIG_SPARC64) += jump_label.o diff --git a/arch/sparc/kernel/ptrace_64.c b/arch/sparc/kernel/ptrace_64.c index ac082dd8c67d..96494b2ef41f 100644 --- a/arch/sparc/kernel/ptrace_64.c +++ b/arch/sparc/kernel/ptrace_64.c @@ -46,6 +46,43 @@ /* #define ALLOW_INIT_TRACING */ +struct pt_regs_offset { + const char *name; + int offset; +}; + +#define REG_OFFSET_NAME(n, r) \ + {.name = n, .offset = (PT_V9_##r)} +#define REG_OFFSET_END {.name = NULL, .offset = 0} + +static const struct pt_regs_offset regoffset_table[] = { + REG_OFFSET_NAME("g0", G0), + REG_OFFSET_NAME("g1", G1), + REG_OFFSET_NAME("g2", G2), + REG_OFFSET_NAME("g3", G3), + REG_OFFSET_NAME("g4", G4), + REG_OFFSET_NAME("g5", G5), + REG_OFFSET_NAME("g6", G6), + REG_OFFSET_NAME("g7", G7), + + REG_OFFSET_NAME("i0", I0), + REG_OFFSET_NAME("i1", I1), + REG_OFFSET_NAME("i2", I2), + REG_OFFSET_NAME("i3", I3), + REG_OFFSET_NAME("i4", I4), + REG_OFFSET_NAME("i5", I5), + REG_OFFSET_NAME("i6", I6), + REG_OFFSET_NAME("i7", I7), + + REG_OFFSET_NAME("tstate", TSTATE), + REG_OFFSET_NAME("pc", TPC), + REG_OFFSET_NAME("npc", TNPC), + REG_OFFSET_NAME("y", Y), + REG_OFFSET_NAME("lr", I7), + + REG_OFFSET_END, +}; + /* * Called by kernel/ptrace.c when detaching.. * @@ -1107,3 +1144,20 @@ asmlinkage void syscall_trace_leave(struct pt_regs *regs) if (test_thread_flag(TIF_NOHZ)) user_enter(); } + +/** + * regs_query_register_offset() - query register offset from its name + * @name: the name of a register + * + * regs_query_register_offset() returns the offset of a register in struct + * pt_regs from its name. If the name is invalid, this returns -EINVAL; + */ +int regs_query_register_offset(const char *name) +{ + const struct pt_regs_offset *roff; + + for (roff = regoffset_table; roff->name != NULL; roff++) + if (!strcmp(roff->name, name)) + return roff->offset; + return -EINVAL; +} diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c index 5ee930c48f4c..c782c9b716db 100644 --- a/arch/sparc/kernel/signal_64.c +++ b/arch/sparc/kernel/signal_64.c @@ -545,6 +545,8 @@ static void do_signal(struct pt_regs *regs, unsigned long orig_i0) void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags) { user_exit(); + if (thread_info_flags & _TIF_UPROBE) + uprobe_notify_resume(regs); if (thread_info_flags & _TIF_SIGPENDING) do_signal(regs, orig_i0); if (thread_info_flags & _TIF_NOTIFY_RESUME) { diff --git a/arch/sparc/kernel/ttable_64.S b/arch/sparc/kernel/ttable_64.S index c6dfdaa29e20..7bd8f6556352 100644 --- a/arch/sparc/kernel/ttable_64.S +++ b/arch/sparc/kernel/ttable_64.S @@ -165,7 +165,7 @@ tl0_resv169: BTRAP(0x169) BTRAP(0x16a) BTRAP(0x16b) BTRAP(0x16c) tl0_linux64: LINUX_64BIT_SYSCALL_TRAP tl0_gsctx: TRAP(sparc64_get_context) TRAP(sparc64_set_context) tl0_resv170: KPROBES_TRAP(0x170) KPROBES_TRAP(0x171) KGDB_TRAP(0x172) -tl0_resv173: BTRAP(0x173) BTRAP(0x174) BTRAP(0x175) BTRAP(0x176) BTRAP(0x177) +tl0_resv173: UPROBES_TRAP(0x173) UPROBES_TRAP(0x174) BTRAP(0x175) BTRAP(0x176) BTRAP(0x177) tl0_resv178: BTRAP(0x178) BTRAP(0x179) BTRAP(0x17a) BTRAP(0x17b) BTRAP(0x17c) tl0_resv17d: BTRAP(0x17d) BTRAP(0x17e) BTRAP(0x17f) #define BTRAPS(x) BTRAP(x) BTRAP(x+1) BTRAP(x+2) BTRAP(x+3) BTRAP(x+4) BTRAP(x+5) BTRAP(x+6) BTRAP(x+7) diff --git a/arch/sparc/kernel/uprobes.c b/arch/sparc/kernel/uprobes.c new file mode 100644 index 000000000000..b68314050602 --- /dev/null +++ b/arch/sparc/kernel/uprobes.c @@ -0,0 +1,331 @@ +/* + * User-space Probes (UProbes) for sparc + * + * Copyright (C) 2013 Oracle Inc. + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + * Authors: + * Jose E. Marchesi <jose.marchesi@oracle.com> + * Eric Saint Etienne <eric.saint.etienne@oracle.com> + */ + +#include <linux/kernel.h> +#include <linux/highmem.h> +#include <linux/uprobes.h> +#include <linux/uaccess.h> +#include <linux/sched.h> /* For struct task_struct */ +#include <linux/kdebug.h> + +#include <asm/cacheflush.h> +#include <asm/uaccess.h> + +/* Compute the address of the breakpoint instruction and return it. + * + * Note that uprobe_get_swbp_addr is defined as a weak symbol in + * kernel/events/uprobe.c. + */ +unsigned long uprobe_get_swbp_addr(struct pt_regs *regs) +{ + return instruction_pointer(regs); +} + +static void copy_to_page(struct page *page, unsigned long vaddr, + const void *src, int len) +{ + void *kaddr = kmap_atomic(page); + + memcpy(kaddr + (vaddr & ~PAGE_MASK), src, len); + kunmap_atomic(kaddr); +} + +/* Fill in the xol area with the probed instruction followed by the + * single-step trap. Some fixups in the copied instruction are + * performed at this point. + * + * Note that uprobe_xol_copy is defined as a weak symbol in + * kernel/events/uprobe.c. + */ +void arch_uprobe_copy_ixol(struct page *page, unsigned long vaddr, + void *src, unsigned long len) +{ + const u32 stp_insn = UPROBE_STP_INSN; + u32 insn = *(u32 *) src; + + /* Branches annulling their delay slot must be fixed to not do + * so. Clearing the annul bit on these instructions we can be + * sure the single-step breakpoint in the XOL slot will be + * executed. + */ + + u32 op = (insn >> 30) & 0x3; + u32 op2 = (insn >> 22) & 0x7; + + if (op == 0 && + (op2 == 1 || op2 == 2 || op2 == 3 || op2 == 5 || op2 == 6) && + (insn & ANNUL_BIT) == ANNUL_BIT) + insn &= ~ANNUL_BIT; + + copy_to_page(page, vaddr, &insn, len); + copy_to_page(page, vaddr+len, &stp_insn, 4); +} + + +/* Instruction analysis/validity. + * + * This function returns 0 on success or a -ve number on error. + */ +int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, + struct mm_struct *mm, unsigned long addr) +{ + /* Any unsupported instruction? Then return -EINVAL */ + return 0; +} + +/* If INSN is a relative control transfer instruction, return the + * corrected branch destination value. + * + * Note that regs->tpc and regs->tnpc still hold the values of the + * program counters at the time of the single-step trap due to the + * execution of the UPROBE_STP_INSN at utask->xol_vaddr + 4. + * + */ +static unsigned long relbranch_fixup(u32 insn, struct uprobe_task *utask, + struct pt_regs *regs) +{ + /* Branch not taken, no mods necessary. */ + if (regs->tnpc == regs->tpc + 0x4UL) + return utask->autask.saved_tnpc + 0x4UL; + + /* The three cases are call, branch w/prediction, + * and traditional branch. + */ + if ((insn & 0xc0000000) == 0x40000000 || + (insn & 0xc1c00000) == 0x00400000 || + (insn & 0xc1c00000) == 0x00800000) { + unsigned long real_pc = (unsigned long) utask->vaddr; + unsigned long ixol_addr = utask->xol_vaddr; + + /* The instruction did all the work for us + * already, just apply the offset to the correct + * instruction location. + */ + return (real_pc + (regs->tnpc - ixol_addr)); + } + + /* It is jmpl or some other absolute PC modification instruction, + * leave NPC as-is. + */ + return regs->tnpc; +} + +/* If INSN is an instruction which writes its PC location + * into a destination register, fix that up. + */ +static int retpc_fixup(struct pt_regs *regs, u32 insn, + unsigned long real_pc) +{ + unsigned long *slot = NULL; + int rc = 0; + + /* Simplest case is 'call', which always uses %o7 */ + if ((insn & 0xc0000000) == 0x40000000) + slot = ®s->u_regs[UREG_I7]; + + /* 'jmpl' encodes the register inside of the opcode */ + if ((insn & 0xc1f80000) == 0x81c00000) { + unsigned long rd = ((insn >> 25) & 0x1f); + + if (rd <= 15) { + slot = ®s->u_regs[rd]; + } else { + unsigned long fp = regs->u_regs[UREG_FP]; + /* Hard case, it goes onto the stack. */ + flushw_all(); + + rd -= 16; + if (test_thread_64bit_stack(fp)) { + unsigned long __user *uslot = + (unsigned long __user *) (fp + STACK_BIAS) + rd; + rc = __put_user(real_pc, uslot); + } else { + unsigned int __user *uslot = (unsigned int + __user *) fp + rd; + rc = __put_user((u32) real_pc, uslot); + } + } + } + if (slot != NULL) + *slot = real_pc; + return rc; +} + +/* Single-stepping can be avoided for certain instructions: NOPs and + * instructions that can be emulated. This function determines + * whether the instruction where the uprobe is installed falls in one + * of these cases and emulates it. + * + * This function returns true if the single-stepping can be skipped, + * false otherwise. + */ +bool arch_uprobe_skip_sstep(struct arch_uprobe *auprobe, struct pt_regs *regs) +{ + /* We currently only emulate NOP instructions. + */ + + if (auprobe->ixol == (1 << 24)) { + regs->tnpc += 4; + regs->tpc += 4; + return true; + } + + return false; +} + +/* Prepare to execute out of line. At this point + * current->utask->xol_vaddr points to an allocated XOL slot properly + * initialized with the original instruction and the single-stepping + * trap instruction. + * + * This function returns 0 on success, any other number on error. + */ +int arch_uprobe_pre_xol(struct arch_uprobe *auprobe, struct pt_regs *regs) +{ + struct uprobe_task *utask = current->utask; + struct arch_uprobe_task *autask = ¤t->utask->autask; + + /* Save the current program counters so they can be restored + * later. + */ + autask->saved_tpc = regs->tpc; + autask->saved_tnpc = regs->tnpc; + + /* Adjust PC and NPC so the first instruction in the XOL slot + * will be executed by the user task. + */ + instruction_pointer_set(regs, utask->xol_vaddr); + + return 0; +} + +/* Prepare to resume execution after the single-step. Called after + * single-stepping. To avoid the SMP problems that can occur when we + * temporarily put back the original opcode to single-step, we + * single-stepped a copy of the instruction. + * + * This function returns 0 on success, any other number on error. + */ +int arch_uprobe_post_xol(struct arch_uprobe *auprobe, struct pt_regs *regs) +{ + struct uprobe_task *utask = current->utask; + struct arch_uprobe_task *autask = &utask->autask; + u32 insn = auprobe->ixol; + int rc = 0; + + if (utask->state == UTASK_SSTEP_ACK) { + regs->tnpc = relbranch_fixup(insn, utask, regs); + regs->tpc = autask->saved_tnpc; + rc = retpc_fixup(regs, insn, (unsigned long) utask->vaddr); + } else { + regs->tnpc = utask->vaddr+4; + regs->tpc = autask->saved_tnpc+4; + } + return rc; +} + +/* Handler for uprobe traps. This is called from the traps table and + * triggers the proper die notification. + */ +asmlinkage void uprobe_trap(struct pt_regs *regs, + unsigned long trap_level) +{ + BUG_ON(trap_level != 0x173 && trap_level != 0x174); + + /* We are only interested in user-mode code. Uprobe traps + * shall not be present in kernel code. + */ + if (!user_mode(regs)) { + local_irq_enable(); + bad_trap(regs, trap_level); + return; + } + + /* trap_level == 0x173 --> ta 0x73 + * trap_level == 0x174 --> ta 0x74 + */ + if (notify_die((trap_level == 0x173) ? DIE_BPT : DIE_SSTEP, + (trap_level == 0x173) ? "bpt" : "sstep", + regs, 0, trap_level, SIGTRAP) != NOTIFY_STOP) + bad_trap(regs, trap_level); +} + +/* Callback routine for handling die notifications. +*/ +int arch_uprobe_exception_notify(struct notifier_block *self, + unsigned long val, void *data) +{ + int ret = NOTIFY_DONE; + struct die_args *args = (struct die_args *)data; + + /* We are only interested in userspace traps */ + if (args->regs && !user_mode(args->regs)) + return NOTIFY_DONE; + + switch (val) { + case DIE_BPT: + if (uprobe_pre_sstep_notifier(args->regs)) + ret = NOTIFY_STOP; + break; + + case DIE_SSTEP: + if (uprobe_post_sstep_notifier(args->regs)) + ret = NOTIFY_STOP; + + default: + break; + } + + return ret; +} + +/* This function gets called when a XOL instruction either gets + * trapped or the thread has a fatal signal, so reset the instruction + * pointer to its probed address. + */ +void arch_uprobe_abort_xol(struct arch_uprobe *auprobe, struct pt_regs *regs) +{ + struct uprobe_task *utask = current->utask; + + instruction_pointer_set(regs, utask->vaddr); +} + +/* If xol insn itself traps and generates a signal(Say, + * SIGILL/SIGSEGV/etc), then detect the case where a singlestepped + * instruction jumps back to its own address. + */ +bool arch_uprobe_xol_was_trapped(struct task_struct *t) +{ + return false; +} + +unsigned long +arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr, + struct pt_regs *regs) +{ + unsigned long orig_ret_vaddr = regs->u_regs[UREG_I7]; + + regs->u_regs[UREG_I7] = trampoline_vaddr-8; + + return orig_ret_vaddr + 8; +} diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h index 4a29c75b146e..0a294e950df8 100644 --- a/include/linux/uprobes.h +++ b/include/linux/uprobes.h @@ -27,6 +27,7 @@ #include <linux/errno.h> #include <linux/rbtree.h> #include <linux/types.h> +#include <linux/wait.h> struct vm_area_struct; struct mm_struct; |