X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Fptrace.c;h=82a558b655dabb9dc7990aedc804b9b04d8f1525;hb=d638d4990bfb99998420e78e8fd4607bca5cf8d0;hp=9a111f70145c6673cddf08eeaf2e86da03dff8d8;hpb=b20e481ab595e9667c33e2393bdfe9a31870d11f;p=linux-2.6 diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 9a111f7014..82a558b655 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include @@ -141,7 +142,7 @@ static int may_attach(struct task_struct *task) return -EPERM; smp_rmb(); if (task->mm) - dumpable = task->mm->dumpable; + dumpable = get_dumpable(task->mm); if (!dumpable && !capable(CAP_SYS_PTRACE)) return -EPERM; @@ -160,6 +161,9 @@ int ptrace_may_attach(struct task_struct *task) int ptrace_attach(struct task_struct *task) { int retval; + unsigned long flags; + + audit_ptrace(task); retval = -EPERM; if (task->pid <= 1) @@ -178,9 +182,7 @@ repeat: * cpu's that may have task_lock). */ task_lock(task); - local_irq_disable(); - if (!write_trylock(&tasklist_lock)) { - local_irq_enable(); + if (!write_trylock_irqsave(&tasklist_lock, flags)) { task_unlock(task); do { cpu_relax(); @@ -208,7 +210,7 @@ repeat: force_sig_specific(SIGSTOP, task); bad: - write_unlock_irq(&tasklist_lock); + write_unlock_irqrestore(&tasklist_lock, flags); task_unlock(task); out: return retval; @@ -241,60 +243,6 @@ int ptrace_detach(struct task_struct *child, unsigned int data) return 0; } -/* - * Access another process' address space. - * Source/target buffer must be kernel space, - * Do not walk the page table directly, use get_user_pages - */ - -int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write) -{ - struct mm_struct *mm; - struct vm_area_struct *vma; - struct page *page; - void *old_buf = buf; - - mm = get_task_mm(tsk); - if (!mm) - return 0; - - down_read(&mm->mmap_sem); - /* ignore errors, just check how much was sucessfully transfered */ - while (len) { - int bytes, ret, offset; - void *maddr; - - ret = get_user_pages(tsk, mm, addr, 1, - write, 1, &page, &vma); - if (ret <= 0) - break; - - bytes = len; - offset = addr & (PAGE_SIZE-1); - if (bytes > PAGE_SIZE-offset) - bytes = PAGE_SIZE-offset; - - maddr = kmap(page); - if (write) { - copy_to_user_page(vma, page, addr, - maddr + offset, buf, bytes); - set_page_dirty_lock(page); - } else { - copy_from_user_page(vma, page, addr, - buf, maddr + offset, bytes); - } - kunmap(page); - page_cache_release(page); - len -= bytes; - buf += bytes; - addr += bytes; - } - up_read(&mm->mmap_sem); - mmput(mm); - - return buf - old_buf; -} - int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len) { int copied = 0; @@ -494,6 +442,7 @@ struct task_struct *ptrace_get_task_struct(pid_t pid) child = find_task_by_pid(pid); if (child) get_task_struct(child); + read_unlock(&tasklist_lock); if (!child) return ERR_PTR(-ESRCH); @@ -541,3 +490,22 @@ asmlinkage long sys_ptrace(long request, long pid, long addr, long data) return ret; } #endif /* __ARCH_SYS_PTRACE */ + +int generic_ptrace_peekdata(struct task_struct *tsk, long addr, long data) +{ + unsigned long tmp; + int copied; + + copied = access_process_vm(tsk, addr, &tmp, sizeof(tmp), 0); + if (copied != sizeof(tmp)) + return -EIO; + return put_user(tmp, (unsigned long __user *)data); +} + +int generic_ptrace_pokedata(struct task_struct *tsk, long addr, long data) +{ + int copied; + + copied = access_process_vm(tsk, addr, &data, sizeof(data), 1); + return (copied == sizeof(data)) ? 0 : -EIO; +}