Re: uprobe: checking probe event include directory

From: Jovi Zhang
Date: Tue Jul 17 2012 - 22:36:29 EST


On Wed, Jul 18, 2012 at 1:27 AM, Srikar Dronamraju
<srikar@xxxxxxxxxxxxxxxxxx> wrote:
> * Frederic Weisbecker <fweisbec@xxxxxxxxx> [2012-07-17 12:59:39]:
>
>> On Tue, Jul 17, 2012 at 06:12:28PM +0800, Jovi Zhang wrote:
>> > From 16ed13ee9098ae01705e8456005d1ad6d9909128 Mon Sep 17 00:00:00 2001
>> > From: Jovi Zhang <bookjovi@xxxxxxxxx>
>> > Date: Wed, 18 Jul 2012 01:16:23 +0800
>> > Subject: [PATCH] uprobe: checking probe event include directory
>> >
>> > Currently below command run successful:
>> > $ echo 'p /bin:0x4245c0' > /sys/kernel/debug/tracing/uprobe_events
>
> good catch.
>
>> >
>> > this don't make sense, because /bin is a directory,
>> > so make this checking earily, not report error untill probe enable.
>> >
>> > Signed-off-by: Jovi Zhang <bookjovi@xxxxxxxxx>
>>
>> Adding Srikar in Cc.
>>
>> > ---
>> > kernel/trace/trace_uprobe.c | 5 +++++
>> > 1 file changed, 5 insertions(+)
>> >
>> > diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
>> > index 85158fa..cf382de 100644
>> > --- a/kernel/trace/trace_uprobe.c
>> > +++ b/kernel/trace/trace_uprobe.c
>> > @@ -259,6 +259,11 @@ static int create_trace_uprobe(int argc, char **argv)
>> > goto fail_address_parse;
>> >
>> > inode = igrab(path.dentry->d_inode);
>> > + if (S_ISDIR(inode->i_mode)) {
>
> How about checking for regular files but not directory.
> i.e it should avoid tracing special files
>
> Something like:
>
> if (!S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)) {
>
>> > + ret = -EINVAL;
>> > + pr_info("probe file cannot be directory.\n");
>
> we could drop the pr_info line here, since we would any print we
> failed to parse the address.
>
> Probably you could change the last pr_info from
>
> pr_info("Failed to parse address.\n");
>
> to
>
> pr_info("Failed to parse address or file.\n");
>
>

Thanks srikar, try below patch: