On Tue, Feb 16, 2021 at 12:50:29PM +0100, Pavel Machek wrote:
Hi!
From: Vincenzo Frascino vincenzo.frascino@arm.com
[ Upstream commit 49c6631d3b4f61a7b5bb0453a885a12bfa06ffd8 ]
Patch series "kasan: Fix metadata detection for KASAN_HW_TAGS", v5.
With the introduction of KASAN_HW_TAGS, kasan_report() currently assumes that every location in memory has valid metadata associated. This is due to the fact that addr_has_metadata() returns always true.
As a consequence of this, an invalid address (e.g. NULL pointer address) passed to kasan_report() when KASAN_HW_TAGS is enabled, leads to a kernel panic.
...
This patch (of 2):
With the introduction of KASAN_HW_TAGS, kasan_report() accesses the metadata only when addr_has_metadata() succeeds.
Add a comment to make sure that the preconditions to the function are explicitly clarified.
As the other patch from the series is not applied, I don't believe we need this in stable. Changelog does not make any sense with just comment change cherry-picked...
Good point, now dropped, the AUTOBOT triggered off of the changelog text which is nice and scary :)
greg k-h