public inbox for linux-arm-kernel@lists.infradead.org 
 help / color / mirror / Atom feed
From: Manish Baing <manishbaing2789@gmail•com>
To: perex@perex•cz, tiwai@suse•com, nicolas.ferre@microchip•com,
	alexandre.belloni@bootlin•com, claudiu.beznea@tuxon•dev
Cc: linux-sound@vger•kernel.org,
	linux-arm-kernel@lists•infradead.org,
	linux-kernel@vger•kernel.org, manishbaing2789@gmail•com,
	Sashiko AI <sashiko-bot@kernel•org>
Subject: [RFC PATCH 2/2] ASoC: atmel: ac97c: Fix use-after-free on driver teardown
Date: Thu,  4 Jun 2026 20:36:23 +0000	[thread overview]
Message-ID: <20260604203623.162640-3-manishbaing2789@gmail.com> (raw)
In-Reply-To: <20260604203623.162640-1-manishbaing2789@gmail.com>

In atmel_ac97c_remove() and the probe error path, the driver disables
clocks and unmaps memory before freeing the IRQ. If a stray interrupt
fires during this window, the handler will attempt to access unmapped
memory or unclocked hardware, resulting in a kernel panic.

Reorder the teardown sequence to call free_irq() first, adhering to
the standard reverse-initialization order.

Running make W=1 returns no errors. I was unable to test the patch
because I do not have the hardware.The issue was flagged by the
Sashiko AI bot.

Link: https://sashiko.dev/#/patchset/20260530052812.115994-1-manishbaing2789@gmail.com?part=1
Reported-by: Sashiko AI <sashiko-bot@kernel•org>
Signed-off-by: Manish Baing <manishbaing2789@gmail•com>
---
 sound/atmel/ac97c.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/sound/atmel/ac97c.c b/sound/atmel/ac97c.c
index cd74395dd222..b9280b644f26 100644
--- a/sound/atmel/ac97c.c
+++ b/sound/atmel/ac97c.c
@@ -790,7 +790,7 @@ static int atmel_ac97c_probe(struct platform_device *pdev)
 	retval = snd_card_register(card);
 	if (retval) {
 		dev_dbg(&pdev->dev, "could not register sound card\n");
-		goto err_ac97_bus;
+		goto err_snd_card_register;
 	}
 
 	platform_set_drvdata(pdev, card);
@@ -800,11 +800,12 @@ static int atmel_ac97c_probe(struct platform_device *pdev)
 
 	return 0;
 
+err_snd_card_register:
+	free_irq(irq, chip);
 err_ac97_bus:
+err_request_irq:
 	iounmap(chip->regs);
 err_ioremap:
-	free_irq(irq, chip);
-err_request_irq:
 	snd_card_free(card);
 err_snd_card_new:
 	clk_disable_unprepare(pclk);
@@ -842,10 +843,10 @@ static void atmel_ac97c_remove(struct platform_device *pdev)
 	ac97c_writel(chip, COMR, 0);
 	ac97c_writel(chip, MR,   0);
 
+	free_irq(chip->irq, chip);
 	clk_disable_unprepare(chip->pclk);
 	clk_put(chip->pclk);
 	iounmap(chip->regs);
-	free_irq(chip->irq, chip);
 
 	snd_card_free(card);
 }
-- 
2.43.0



      parent reply	other threads:[~2026-06-04 20:37 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-06-04 20:36 [RFC PATCH 0/2] ASoC: atmel: ac97c: Fix IRQ handling sequences Manish Baing
2026-06-04 20:36 ` [RFC PATCH 1/2] ASoC: sound: atmel_ac97c: Fix IRQ handler null pointer dereference Manish Baing
2026-06-04 20:36 ` Manish Baing [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260604203623.162640-3-manishbaing2789@gmail.com \
    --to=manishbaing2789@gmail$(echo .)com \
    --cc=alexandre.belloni@bootlin$(echo .)com \
    --cc=claudiu.beznea@tuxon$(echo .)dev \
    --cc=linux-arm-kernel@lists$(echo .)infradead.org \
    --cc=linux-kernel@vger$(echo .)kernel.org \
    --cc=linux-sound@vger$(echo .)kernel.org \
    --cc=nicolas.ferre@microchip$(echo .)com \
    --cc=perex@perex$(echo .)cz \
    --cc=sashiko-bot@kernel$(echo .)org \
    --cc=tiwai@suse$(echo .)com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox