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Re: nfs.proc.open results in a kernel string copy fault
David Smith <dsmith@redhat.com> writes:
> [...]
> The only reference to '$filp' in probe nfs.proc.open is the following:
> filename = __file_filename($filp)
> The __file_filename function is defined in tapset/vfs.stp, and it
> looks reasonable to me. [...]
But it isn't really. Nullness testing is not sufficient for such
pointers - they may be invalid pointers for a variety of reasons
such as bad debuginfo. So such functions should use protected
functions equivalent to kernel_string().
I wonder why __file_filename() is used at all -- why is
kernel_string($filp->f_dentry->d_name.name)
not sufficient?
- FChE