diff options
Diffstat (limited to 'arch/ia64/kernel/ptrace.c')
| -rw-r--r-- | arch/ia64/kernel/ptrace.c | 27 |
1 files changed, 24 insertions, 3 deletions
diff --git a/arch/ia64/kernel/ptrace.c b/arch/ia64/kernel/ptrace.c index 55789fcd7210..9e730c7bf0cd 100644 --- a/arch/ia64/kernel/ptrace.c +++ b/arch/ia64/kernel/ptrace.c @@ -17,6 +17,7 @@ #include <linux/user.h> #include <linux/security.h> #include <linux/audit.h> +#include <linux/signal.h> #include <asm/pgtable.h> #include <asm/processor.h> @@ -704,12 +705,32 @@ convert_to_non_syscall (struct task_struct *child, struct pt_regs *pt, break; } + /* + * Note: at the time of this call, the target task is blocked + * in notify_resume_user() and by clearling PRED_LEAVE_SYSCALL + * (aka, "pLvSys") we redirect execution from + * .work_pending_syscall_end to .work_processed_kernel. + */ unw_get_pr(&prev_info, &pr); - pr &= ~(1UL << PRED_SYSCALL); + pr &= ~((1UL << PRED_SYSCALL) | (1UL << PRED_LEAVE_SYSCALL)); pr |= (1UL << PRED_NON_SYSCALL); unw_set_pr(&prev_info, pr); pt->cr_ifs = (1UL << 63) | cfm; + /* + * Clear the memory that is NOT written on syscall-entry to + * ensure we do not leak kernel-state to user when execution + * resumes. + */ + pt->r2 = 0; + pt->r3 = 0; + pt->r14 = 0; + memset(&pt->r16, 0, 16*8); /* clear r16-r31 */ + memset(&pt->f6, 0, 6*16); /* clear f6-f11 */ + pt->b7 = 0; + pt->ar_ccv = 0; + pt->ar_csd = 0; + pt->ar_ssd = 0; } static int @@ -1481,7 +1502,7 @@ sys_ptrace (long request, pid_t pid, unsigned long addr, unsigned long data) case PTRACE_CONT: /* restart after signal. */ ret = -EIO; - if (data > _NSIG) + if (!valid_signal(data)) goto out_tsk; if (request == PTRACE_SYSCALL) set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); @@ -1520,7 +1541,7 @@ sys_ptrace (long request, pid_t pid, unsigned long addr, unsigned long data) /* let child execute for one instruction */ case PTRACE_SINGLEBLOCK: ret = -EIO; - if (data > _NSIG) + if (!valid_signal(data)) goto out_tsk; clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |