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charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam11 X-Stat-Signature: a6p9mikhnrm3o5fpx4snhrhws3kpcz4r X-Rspam-User: X-Rspamd-Queue-Id: 8A2C41A0008 X-HE-Tag: 1770408871-882931 X-HE-Meta: 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 AnJzpDDA VpvzCDbneRiB+xC3yamiiYISqNHGr0S3lwb9qnx4xN7WPIrSB7KZ9DnL5JZ4WpOZod0rUKi86YE1r0aYvSU8vah91MMZ4vmTk4RDy2Fsjh7a7nLCSFZaXYGZrrI7X5gUL0+3u1p1zmO2oOw5fGwQr9yO7zlQOQqK34NxqEzUQbz/3762pVA8PmJ6WmY+NfoQzj3j35UsomivySsO1xtH1kZk/FnqMBQITh0oRzuEaGsGSZtURCl4IPs+j1coI3Ac+X7NFY66qFaxeAVV4V6YOWXJSeBO92eAsB0IacKzW3+EK3Z8= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: >From what I see kasan_poison_last_granule() is called through: __kasan_vrealloc() --> __kasan_unpoison_vmalloc() ----> kasan_unpoison() ------> kasan_poison_last_granule() and the arguments are "addr + old_size" and "new_size - old_size" so it loo= ks okay I think. On 2026-02-06 at 11:07:12 -0800, Maciej =C5=BBenczykowski wrote: >While looking at: > https://android-review.git.corp.google.com/c/kernel/common/+/3939998 > UPSTREAM: mm/kasan: fix KASAN poisoning in vrealloc() > >I noticed a lack of symmetry - I'm not sure if it's a problem or not... >but I'd have expected kasan_poison_last_granule() to be called >regardless of whether the size shrunk or increased. > >It is of course possible this is handled automatically by >__kasan_unpoison_vmalloc() - I haven't traced that deep, >in general these functions seem to have a terrible api surface full of >razors... with hidden assumptions about what is and is not granule >aligned. --=20 Kind regards Maciej Wiecz=C3=B3r-Retman