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From: sashiko-bot@kernel.org
To: leixiang <leixiang@kylinos.cn>
Cc: linux-pci@vger.kernel.org
Subject: Re: [PATCH] PCI/P2PDMA: Fix use-after-free in pci_p2pdma_add_resource() error path
Date: Fri, 17 Jul 2026 10:00:19 +0000	[thread overview]
Message-ID: <20260717100019.BE93F1F00A3A@smtp.kernel.org> (raw)
In-Reply-To: <20260717095120.51111-1-leixiang@kylinos.cn>

> In pci_p2pdma_add_resource(), a devm action is registered to call
> pci_p2pdma_unmap_mappings() with the 'p2p_pgmap' context. If the subsequent
> call to gen_pool_add_owner() fails, the code jumps to the 'pages_free'
> error path.
> 
> In this error path, 'p2p_pgmap' is explicitly freed via devm_kfree().
> However, the previously registered devm action is never removed. This
> leaves a dangling pointer in the device's devres list. When the device
> is unbound and devres is cleaning up resources, the unmap action will be
> called with the already-freed 'p2p_pgmap', resulting in a use-after-free
> bug.
> 
> Fix this by properly calling devm_remove_action() in the error path before
> freeing 'p2p_pgmap'.
> 
> Fixes: 7e9c7ef83d78 ("PCI/P2PDMA: Allow userspace VMA allocations through sysfs")
> Assisted-by: Antigravity:Gemini [tools]
> Signed-off-by: leixiang <leixiang@kylinos.cn>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260717095120.51111-1-leixiang@kylinos.cn?part=1


  reply	other threads:[~2026-07-17 10:00 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-07-17  9:51 [PATCH] PCI/P2PDMA: Fix use-after-free in pci_p2pdma_add_resource() error path leixiang
2026-07-17 10:00 ` sashiko-bot [this message]
2026-07-17 10:48 ` Greg Kroah-Hartman

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