From: Roland McGrath Date: Thu, 7 Aug 2008 23:55:03 +0000 (-0700) Subject: tracehook: fix CLONE_PTRACE X-Git-Tag: v2.6.27-rc3~72^2 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5861bbfcc10fc0358abf52c7d22850c8d180f0b0;p=linux-2.6 tracehook: fix CLONE_PTRACE In the change in commit 09a05394fe2448a4139b014936330af23fa7ec83, I overlooked two nits in the logic and this broke using CLONE_PTRACE when PTRACE_O_TRACE* are not being used. A parent that is itself traced at all but not using PTRACE_O_TRACE*, using CLONE_PTRACE would have its new child fail to be traced. A parent that is not itself traced at all that uses CLONE_PTRACE (which should be a no-op in this case) would confuse the bookkeeping and lead to a crash at exit time. This restores the missing checks and fixes both failure modes. Reported-by: Eduardo Habkost Signed-off-by: Roland McGrath --- diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h index fd31756e1a..ea7416c901 100644 --- a/include/linux/ptrace.h +++ b/include/linux/ptrace.h @@ -172,7 +172,7 @@ static inline void ptrace_init_task(struct task_struct *child, bool ptrace) child->ptrace = 0; if (unlikely(ptrace)) { child->ptrace = current->ptrace; - __ptrace_link(child, current->parent); + ptrace_link(child, current->parent); } } diff --git a/include/linux/tracehook.h b/include/linux/tracehook.h index ab3ef7aefa..b48d819695 100644 --- a/include/linux/tracehook.h +++ b/include/linux/tracehook.h @@ -280,7 +280,7 @@ static inline void tracehook_report_clone(int trace, struct pt_regs *regs, unsigned long clone_flags, pid_t pid, struct task_struct *child) { - if (unlikely(trace)) { + if (unlikely(trace) || unlikely(clone_flags & CLONE_PTRACE)) { /* * The child starts up with an immediate SIGSTOP. */