diff options
| author | Roland McGrath <roland@redhat.com> | 2004-08-22 22:47:28 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2004-08-22 22:47:28 -0700 |
| commit | cae7c30af0190d6af4829a4e5a95fa43b5f01413 (patch) | |
| tree | abf39febf720a2957f020ab9a4028af5c5aaa98a /arch | |
| parent | b9cbc585eda36c84edbf05c0e83e3bf950ff45fa (diff) | |
| download | history-cae7c30af0190d6af4829a4e5a95fa43b5f01413.tar.gz | |
[PATCH] Fix x86-64 singlestep through sigreturn system call
This patch just directly clones Davide Libenzi's i386 code for x86-64 in
both 64-bit and 32-bit cases. With this, the behavior of single-stepping
all system calls is consistent.
The syscall exit tracing caused by TIF_SINGLESTEP is superfluous in the
case of sysret returns, but harmlessly so (since continuing afterward with
PTRACE_CONT will have cleared TF as well as TIF_SINGLESTEP). I figured
that little bit of extra processing in the single-step case was better than
adding code to ignore the flag in the sysret case.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86_64/kernel/entry.S | 3 | ||||
| -rw-r--r-- | arch/x86_64/kernel/ptrace.c | 7 |
2 files changed, 8 insertions, 2 deletions
diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index 89f74f738a2a6f..cf008e67422ff5 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -297,7 +297,7 @@ int_very_careful: sti SAVE_REST /* Check for syscall exit trace */ - testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT),%edx + testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP),%edx jz int_signal pushq %rdi leaq 8(%rsp),%rdi # &ptregs -> arg1 @@ -305,6 +305,7 @@ int_very_careful: popq %rdi btr $TIF_SYSCALL_TRACE,%edi btr $TIF_SYSCALL_AUDIT,%edi + btr $TIF_SINGLESTEP,%edi jmp int_restore_rest int_signal: diff --git a/arch/x86_64/kernel/ptrace.c b/arch/x86_64/kernel/ptrace.c index 5dd7752ae7656f..8e3431564f2530 100644 --- a/arch/x86_64/kernel/ptrace.c +++ b/arch/x86_64/kernel/ptrace.c @@ -88,6 +88,7 @@ void ptrace_disable(struct task_struct *child) { long tmp; + clear_tsk_thread_flag(child, TIF_SINGLESTEP); tmp = get_stack_long(child, EFL_OFFSET) & ~TRAP_FLAG; put_stack_long(child, EFL_OFFSET, tmp); } @@ -344,6 +345,7 @@ asmlinkage long sys_ptrace(long request, long pid, unsigned long addr, long data set_tsk_thread_flag(child,TIF_SYSCALL_TRACE); else clear_tsk_thread_flag(child,TIF_SYSCALL_TRACE); + clear_tsk_thread_flag(child, TIF_SINGLESTEP); child->exit_code = data; /* make sure the single step bit is not set. */ tmp = get_stack_long(child, EFL_OFFSET); @@ -395,6 +397,7 @@ asmlinkage long sys_ptrace(long request, long pid, unsigned long addr, long data ret = 0; if (child->state == TASK_ZOMBIE) /* already dead */ break; + clear_tsk_thread_flag(child, TIF_SINGLESTEP); child->exit_code = SIGKILL; /* make sure the single step bit is not set. */ tmp = get_stack_long(child, EFL_OFFSET) & ~TRAP_FLAG; @@ -416,6 +419,7 @@ asmlinkage long sys_ptrace(long request, long pid, unsigned long addr, long data } tmp = get_stack_long(child, EFL_OFFSET) | TRAP_FLAG; put_stack_long(child, EFL_OFFSET, tmp); + set_tsk_thread_flag(child, TIF_SINGLESTEP); child->exit_code = data; /* give it a chance to run. */ wake_up_process(child); @@ -528,7 +532,8 @@ asmlinkage void syscall_trace_leave(struct pt_regs *regs) if (unlikely(current->audit_context)) audit_syscall_exit(current, regs->rax); - if (test_thread_flag(TIF_SYSCALL_TRACE) + if ((test_thread_flag(TIF_SYSCALL_TRACE) + || test_thread_flag(TIF_SINGLESTEP)) && (current->ptrace & PT_PTRACED)) syscall_trace(regs); } |