perf/amd/ibs: Prevent leaking sensitive data to userspace

Although IBS "swfilt" can prevent leaking samples with kernel RIP to the
userspace, there are few subtle cases where a 'data' address and/or a
'branch target' address can fall under kernel address range although RIP
is from userspace. Prevent leaking kernel 'data' addresses by discarding
such samples when {exclude_kernel=1,swfilt=1}.

IBS can now be invoked by unprivileged user with the introduction of
"swfilt". However, this creates a loophole in the interface where an
unprivileged user can get physical address of the userspace virtual
addresses through IBS register raw dump (PERF_SAMPLE_RAW). Prevent this
as well.

This upstream commit fixed the most obvious leak:

  65a99264f5e5 perf/x86: Check data address for IBS software filter

Follow that up with a more complete fix.

Fixes: d29e744c7167 ("perf/x86: Relax privilege filter restriction on AMD IBS")
Suggested-by: Matteo Rizzo <[email protected]>
Co-developed-by: Ravi Bangoria <[email protected]>
Signed-off-by: Namhyung Kim <[email protected]>
Signed-off-by: Ravi Bangoria <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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