i2c: amd-mp2: Unregister callback on adapter add failure

amd_mp2_register_cb() stores the platform I2C context in the MP2 PCI
driver's callback table before the adapter is registered. If
i2c_add_adapter() fails, probe returns and devres frees the context,
but the PCI driver can still dereference the stale pointer from its IRQ
and system-sleep callbacks.

Unregister the callback before returning the adapter registration error.

Fixes: 529766e0a011 ("i2c: Add drivers for the AMD PCIe MP2 I2C controller")
Co-developed-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
Cc: <stable@vger.kernel.org> # v5.2+
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20260721144147.31150-1-mhun512@gmail.com

diff --git a/drivers/i2c/busses/i2c-amd-mp2-plat.c b/drivers/i2c/busses/i2c-amd-mp2-plat.c
index 188e24cc4d35f14a97161500c7bb0bc7a465dbac..9fdd6a5fb8b65cf23ac65aa8c7b69983a2c1f56b 100644 (file)
--- a/drivers/i2c/busses/i2c-amd-mp2-plat.c
+++ b/drivers/i2c/busses/i2c-amd-mp2-plat.c
@@ -316,8 +316,10 @@ static int i2c_amd_probe(struct platform_device *pdev)
 
        amd_mp2_pm_runtime_put(mp2_dev);
 
-       if (ret < 0)
+       if (ret < 0) {
                dev_err(&pdev->dev, "i2c add adapter failed = %d\n", ret);
+               amd_mp2_unregister_cb(&i2c_dev->common);
+       }
 
        return ret;
 }