From: Sanghyun Park <sanghyun.park.cnu@gmail.com>
To: yonghong.song@linux.dev, ast@kernel.org, daniel@iogearbox.net,
andrii@kernel.org
Cc: Sanghyun Park <sanghyun.park.cnu@gmail.com>,
bpf@vger.kernel.org, linux-kernel@vger.kernel.org,
puranjay@kernel.org
Subject: Re: [PATCH v2] bpf: Fix use-after-free on mm_struct in bpf_find_vma()
Date: Tue, 9 Jun 2026 19:26:15 +0900 [thread overview]
Message-ID: <20260609102618.3508682-2-sanghyun.park.cnu@gmail.com> (raw)
In-Reply-To: <a775c0b8-07f3-4265-8cfd-ec01ffd9efbf@linux.dev>
Hello Yonghong,
Thank you for the feedback. You are right on both points.
In v3 I will drop get_task_mm()+mmput() and instead mirror the pattern
from upstream commit d8e27d2d22b6 ("bpf: fix mm lifecycle in open-coded
task_vma iterator"): use spin_trylock(&task->alloc_lock) to read task->mm
and mmget() to pin it, then release the reference with mmput_async(). I
will also reject irqs-disabled contexts and !CONFIG_MMU on the foreign
path, and fix the whitespace damage.
v3 coming shortly.
Sincerely,
Sanghyun
prev parent reply other threads:[~2026-06-09 10:29 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-05-29 8:01 Sanghyun Park
2026-06-02 5:55 ` Yonghong Song
2026-06-09 10:26 ` Sanghyun Park [this message]
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