lkml.org 
[lkml]   [2018]   [Apr]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Date
    Subject[REVIEW][PATCH 03/17] signal/sh: Use force_sig_fault in hw_breakpoint_handler
    The call chain is:
    breakpoint
    notify_die
    hw_breakpoint_exceptions_notify
    hw_breakpoint_handler

    So the signal number can only be SIGTRAP.

    In hw_breakpoint_handler rc is either NOTIFY_STOP or NOTIF_DONE
    both of which notifier_to_errno converts to 0. So si_errno is 0.

    Historically si_addr was left unitialized in struct siginfo which is a
    bug. There appears to be no consensus among the various architectures
    which value should be in si_addr. So since no usable value has
    been returned up to this point return NULL in si_addr.

    Fixes: 4352fc1b12fa ("sh: Abstracted SH-4A UBC support on hw-breakpoint core.")
    Fixes: 34d0b5af50a0 ("sh: Convert ptrace to hw_breakpoint API.")
    Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
    Cc: Rich Felker <dalias@libc.org>
    Cc: Paul Mundt <lethal@linux-sh.org>
    Cc: linux-sh@vger.kernel.org
    Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
    ---
    arch/sh/kernel/hw_breakpoint.c | 9 ++-------
    1 file changed, 2 insertions(+), 7 deletions(-)

    diff --git a/arch/sh/kernel/hw_breakpoint.c b/arch/sh/kernel/hw_breakpoint.c
    index afe965712a69..8648ed05ccf0 100644
    --- a/arch/sh/kernel/hw_breakpoint.c
    +++ b/arch/sh/kernel/hw_breakpoint.c
    @@ -347,13 +347,8 @@ static int __kprobes hw_breakpoint_handler(struct die_args *args)

    /* Deliver the signal to userspace */
    if (!arch_check_bp_in_kernelspace(bp)) {
    - siginfo_t info;
    -
    - info.si_signo = args->signr;
    - info.si_errno = notifier_to_errno(rc);
    - info.si_code = TRAP_HWBKPT;
    -
    - force_sig_info(args->signr, &info, current);
    + force_sig_fault(SIGTRAP, TRAP_HWBKPT,
    + (void __user *)NULL, current);
    }

    rcu_read_unlock();
    --
    2.14.1
    \
     
     \ /
      Last update: 2018-04-20 03:08    [W:4.103 / U:0.132 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site