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From: Hui Peng <benquike@gmail.com>
To: marcel@holtmann.org, luiz.dentz@gmail.com
Cc: lee@kernel.org, linux-bluetooth@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3] Bluetooth: MGMT: Fix mesh_tx Use-After-Free and leak in mesh_send()
Date: Sat, 19 Sep 2026 11:55:00 +0000	[thread overview]
Message-ID: <178981890089.4001113.207387311305810171@gmail.com> (raw)
In-Reply-To: <20260919112517.3871992-1-benquike@gmail.com>

Please drop this patch, and sorry for the noise.

Two things are wrong with it.

First, the mechanical problem the CI already reported: I based it on
Linus' tree rather than bluetooth-next, so it does not apply.

Second, and more to the point, the use-after-free half of it is no
longer needed. 71af682ba469 ("Bluetooth: mgmt: Dequeue pending
mesh_send_sync entries on cancel") fixed that on 2026-09-15, and fixed
it better than this patch did. It dequeues the pending mesh_send_sync
entry at the point where mesh_tx is freed, which addresses the problem
at its source. What I had done instead was take hci_dev_lock() across
mesh_send_sync() and re-validate mesh_tx against mgmt_mesh_next(), which
only narrows the window for the two callers I happened to look at and
would not help any future path that frees a queued mesh_tx. I should
have checked bluetooth-next before sending.

What does survive is the other half: mesh_tx is leaked when
hci_cmd_sync_queue() fails in mesh_send(), because the cleanup is
guarded by "if (sending)" while that error can only occur when sending
is false. That is still present in bluetooth-next today. I have sent it
separately as a one-hunk patch against the right tree:

  [PATCH] Bluetooth: MGMT: fix mesh_tx leak on hci_cmd_sync_queue() failure
  Message-ID: <20260919115436.3998954-1-benquike@gmail.com>

Hui


      reply	other threads:[~2026-09-19 11:55 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20260919080846.3005471-1-benquike@gmail.com>
2026-09-19 11:25 ` Hui Peng
2026-09-19 11:55   ` Hui Peng [this message]

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