Re: [PATCH 1/2] can: m_can: m_can_plat_probe(): free can_net device in case probe fails
On 05.02.2021 15:25:58, Xulin Sun wrote: > The can_net device is allocated through kvzalloc(), if the subsequent probe > cases fail to initialize, it should free the can_net device that has been > successfully allocated before. > > To fix below memory leaks call trace: > > unreferenced object 0xfc08418b (size 32768): > comm "kworker/0:1", pid 22, jiffies 4294893966 (age 931.976s) > hex dump (first 32 bytes): > 63 61 6e 25 64 00 00 00 00 00 00 00 00 00 00 00 can%d... > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > backtrace: > [<3faec9cc>] __kmalloc+0x1a4/0x3e0 > [<560b1cad>] kvmalloc_node+0xa0/0xb0 > [<93bada32>] alloc_netdev_mqs+0x60/0x380 > [<41ddbb53>] alloc_candev_mqs+0x6c/0x14c > [] m_can_class_allocate_dev+0x64/0x18c > [<9fef1617>] m_can_plat_probe+0x2c/0x1f4 > [<6fdcc497>] platform_drv_probe+0x5c/0xb0 > [ ] really_probe+0xec/0x41c > [<3ffa5158>] driver_probe_device+0x60/0xf0 > [<5986c77e>] __device_attach_driver+0xb0/0x100 > [<757823bc>] bus_for_each_drv+0x8c/0xe0 > [<59253919>] __device_attach+0xdc/0x180 > [<35c2b9f1>] device_initial_probe+0x28/0x34 > [<82e2c85c>] bus_probe_device+0xa4/0xb0 > [ ] deferred_probe_work_func+0x7c/0xb0 > [<01b85f22>] process_one_work+0x1ec/0x480 > > Signed-off-by: Xulin Sun This patch doesn't apply to net/master, since v5.10 there is a similar fix: 85816aba460c can: m_can: Fix freeing of can device from peripherials Please update to latest v5.10.x. If you're on a kernel that's still supported, and you're using the latest stable of that kernel, and it doesn't have that patch applied, ask on linux-stable to pick up that patch. Marc -- Pengutronix e.K. | Marc Kleine-Budde | Embedded Linux | https://www.pengutronix.de | Vertretung West/Dortmund | Phone: +49-231-2826-924 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917- | signature.asc Description: PGP signature
[PATCH 1/2] can: m_can: m_can_plat_probe(): free can_net device in case probe fails
The can_net device is allocated through kvzalloc(), if the subsequent probe cases fail to initialize, it should free the can_net device that has been successfully allocated before. To fix below memory leaks call trace: unreferenced object 0xfc08418b (size 32768): comm "kworker/0:1", pid 22, jiffies 4294893966 (age 931.976s) hex dump (first 32 bytes): 63 61 6e 25 64 00 00 00 00 00 00 00 00 00 00 00 can%d... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 backtrace: [<3faec9cc>] __kmalloc+0x1a4/0x3e0 [<560b1cad>] kvmalloc_node+0xa0/0xb0 [<93bada32>] alloc_netdev_mqs+0x60/0x380 [<41ddbb53>] alloc_candev_mqs+0x6c/0x14c [] m_can_class_allocate_dev+0x64/0x18c [<9fef1617>] m_can_plat_probe+0x2c/0x1f4 [<6fdcc497>] platform_drv_probe+0x5c/0xb0 [ ] really_probe+0xec/0x41c [<3ffa5158>] driver_probe_device+0x60/0xf0 [<5986c77e>] __device_attach_driver+0xb0/0x100 [<757823bc>] bus_for_each_drv+0x8c/0xe0 [<59253919>] __device_attach+0xdc/0x180 [<35c2b9f1>] device_initial_probe+0x28/0x34 [<82e2c85c>] bus_probe_device+0xa4/0xb0 [ ] deferred_probe_work_func+0x7c/0xb0 [<01b85f22>] process_one_work+0x1ec/0x480 Signed-off-by: Xulin Sun --- drivers/net/can/m_can/m_can_platform.c | 10 -- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/net/can/m_can/m_can_platform.c b/drivers/net/can/m_can/m_can_platform.c index 38ea5e600fb8..0a2655c94018 100644 --- a/drivers/net/can/m_can/m_can_platform.c +++ b/drivers/net/can/m_can/m_can_platform.c @@ -67,8 +67,10 @@ static int m_can_plat_probe(struct platform_device *pdev) return -ENOMEM; priv = devm_kzalloc(>dev, sizeof(*priv), GFP_KERNEL); - if (!priv) - return -ENOMEM; + if (!priv) { + ret = -ENOMEM; + goto failed_ret; + } mcan_class->device_data = priv; @@ -113,7 +115,11 @@ static int m_can_plat_probe(struct platform_device *pdev) ret = m_can_class_register(mcan_class); + return ret; + failed_ret: + free_candev(mcan_class->net); + return ret; } -- 2.17.1
