Re: [PATCH] powerpc/fsl_rio: fix a improper release in fsl_rio_setup()
From: "Christophe Leroy (CS GROUP)" <chleroy@kernel.org>
Date: 2025-12-20 10:45:14
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Le 19/12/2025 à 15:10, Haoxiang Li a écrit :
[Vous ne recevez pas souvent de courriers de lihaoxiang@isrc.iscas.ac.cn. Découvrez pourquoi ceci est important à https://aka.ms/LearnAboutSenderIdentification ] If rio_register_mport() fails, put_device() is the correct way to drop the device reference. To prevent a double free, remove put_device() in rio_register_mport() Also, add a put_device() in tsi721_setup_mport() to prevent reference leak.
Your explanation is unclear. It is correct that put_device() is the correct way to drop the device reference, and it is already what rio_register_mport() does. Why do you need to move it out of rio_register_mport() ? This is what you have to explain.
Found by code review.
AI code review or human code review ?
quoted hunk ↗ jump to hunk
Signed-off-by: Haoxiang Li <redacted> --- arch/powerpc/sysdev/fsl_rio.c | 2 +- drivers/rapidio/devices/tsi721.c | 1 + drivers/rapidio/rio.c | 1 - 3 files changed, 2 insertions(+), 2 deletions(-)diff --git a/arch/powerpc/sysdev/fsl_rio.c b/arch/powerpc/sysdev/fsl_rio.c index f9b214b299e7..f6226b2619ed 100644 --- a/arch/powerpc/sysdev/fsl_rio.c +++ b/arch/powerpc/sysdev/fsl_rio.c@@ -697,7 +697,7 @@ static int fsl_rio_setup(struct platform_device *dev) if (rio_register_mport(port)) { release_resource(&port->iores); kfree(priv); - kfree(port);
Why do you remove this kfree() ? By doing this you will leak the port pointer allocated earlier in the loop by kzalloc()
quoted hunk ↗ jump to hunk
+ put_device(&port->dev); continue; } active_ports++;diff --git a/drivers/rapidio/devices/tsi721.c b/drivers/rapidio/devices/tsi721.c index 4b84270a8906..17c2bcf29c5c 100644 --- a/drivers/rapidio/devices/tsi721.c +++ b/drivers/rapidio/devices/tsi721.c@@ -2758,6 +2758,7 @@ static int tsi721_setup_mport(struct tsi721_device *priv) err = rio_register_mport(mport); if (err) { tsi721_unregister_dma(priv); + put_device(&mport->dev); goto err_exit; }diff --git a/drivers/rapidio/rio.c b/drivers/rapidio/rio.c index 46daf32ea13b..026b2328afd7 100644 --- a/drivers/rapidio/rio.c +++ b/drivers/rapidio/rio.c@@ -2089,7 +2089,6 @@ int rio_register_mport(struct rio_mport *port) mutex_lock(&rio_mport_list_lock); list_del(&port->node); mutex_unlock(&rio_mport_list_lock); - put_device(&port->dev); } else { dev_dbg(&port->dev, "RIO: registered mport%d\n", port->id); } --2.25.1