diff options
Diffstat (limited to 'arch/x86/kernel/ptrace.c')
| -rw-r--r-- | arch/x86/kernel/ptrace.c | 59 |
1 files changed, 10 insertions, 49 deletions
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c index a166c960bc9e..71691a8310e7 100644 --- a/arch/x86/kernel/ptrace.c +++ b/arch/x86/kernel/ptrace.c @@ -25,6 +25,7 @@ #include <linux/rcupdate.h> #include <linux/export.h> #include <linux/context_tracking.h> +#include <linux/nospec.h> #include <linux/uaccess.h> #include <asm/pgtable.h> @@ -154,35 +155,6 @@ static inline bool invalid_selector(u16 value) #define FLAG_MASK FLAG_MASK_32 -/* - * X86_32 CPUs don't save ss and esp if the CPU is already in kernel mode - * when it traps. The previous stack will be directly underneath the saved - * registers, and 'sp/ss' won't even have been saved. Thus the '®s->sp'. - * - * Now, if the stack is empty, '®s->sp' is out of range. In this - * case we try to take the previous stack. To always return a non-null - * stack pointer we fall back to regs as stack if no previous stack - * exists. - * - * This is valid only for kernel mode traps. - */ -unsigned long kernel_stack_pointer(struct pt_regs *regs) -{ - unsigned long context = (unsigned long)regs & ~(THREAD_SIZE - 1); - unsigned long sp = (unsigned long)®s->sp; - u32 *prev_esp; - - if (context == (sp & ~(THREAD_SIZE - 1))) - return sp; - - prev_esp = (u32 *)(context); - if (*prev_esp) - return (unsigned long)*prev_esp; - - return (unsigned long)regs; -} -EXPORT_SYMBOL_GPL(kernel_stack_pointer); - static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long regno) { BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0); @@ -397,22 +369,12 @@ static int putreg(struct task_struct *child, case offsetof(struct user_regs_struct,fs_base): if (value >= TASK_SIZE_MAX) return -EIO; - /* - * When changing the FS base, use do_arch_prctl_64() - * to set the index to zero and to set the base - * as requested. - */ - if (child->thread.fsbase != value) - return do_arch_prctl_64(child, ARCH_SET_FS, value); + x86_fsbase_write_task(child, value); return 0; case offsetof(struct user_regs_struct,gs_base): - /* - * Exactly the same here as the %fs handling above. - */ if (value >= TASK_SIZE_MAX) return -EIO; - if (child->thread.gsbase != value) - return do_arch_prctl_64(child, ARCH_SET_GS, value); + x86_gsbase_write_task(child, value); return 0; #endif } @@ -645,7 +607,8 @@ static unsigned long ptrace_get_debugreg(struct task_struct *tsk, int n) unsigned long val = 0; if (n < HBP_NUM) { - struct perf_event *bp = thread->ptrace_bps[n]; + int index = array_index_nospec(n, HBP_NUM); + struct perf_event *bp = thread->ptrace_bps[index]; if (bp) val = bp->hw.info.address; @@ -747,9 +710,6 @@ static int ioperm_get(struct task_struct *target, void ptrace_disable(struct task_struct *child) { user_disable_single_step(child); -#ifdef TIF_SYSCALL_EMU - clear_tsk_thread_flag(child, TIF_SYSCALL_EMU); -#endif } #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION @@ -1361,18 +1321,19 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task) #endif } -void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, - int error_code, int si_code) +void send_sigtrap(struct pt_regs *regs, int error_code, int si_code) { + struct task_struct *tsk = current; + tsk->thread.trap_nr = X86_TRAP_DB; tsk->thread.error_code = error_code; /* Send us the fake SIGTRAP */ force_sig_fault(SIGTRAP, si_code, - user_mode(regs) ? (void __user *)regs->ip : NULL, tsk); + user_mode(regs) ? (void __user *)regs->ip : NULL); } void user_single_step_report(struct pt_regs *regs) { - send_sigtrap(current, regs, 0, TRAP_BRKPT); + send_sigtrap(regs, 0, TRAP_BRKPT); } |