[PATCH 3.18 056/105] mfd: ti_am335x_tscadc: Fix struct clk memory leak

From: Greg Kroah-Hartman
Date: Mon Sep 24 2018 - 07:40:03 EST


3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Zumeng Chen <zumeng.chen@xxxxxxxxx>

[ Upstream commit c2b1509c77a99a0dcea0a9051ca743cb88385f50 ]

Use devm_elk_get() to let Linux manage struct clk memory to avoid the following
memory leakage report:

unreferenced object 0xdd75efc0 (size 64):
comm "systemd-udevd", pid 186, jiffies 4294945126 (age 1195.750s)
hex dump (first 32 bytes):
61 64 63 5f 74 73 63 5f 66 63 6b 00 00 00 00 00 adc_tsc_fck.....
00 00 00 00 92 03 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<c0a15260>] kmemleak_alloc+0x40/0x74
[<c0287a10>] __kmalloc_track_caller+0x198/0x388
[<c0255610>] kstrdup+0x40/0x5c
[<c025565c>] kstrdup_const+0x30/0x3c
[<c0636630>] __clk_create_clk+0x60/0xac
[<c0630918>] clk_get_sys+0x74/0x144
[<c0630cdc>] clk_get+0x5c/0x68
[<bf0ac540>] ti_tscadc_probe+0x260/0x468 [ti_am335x_tscadc]
[<c06f3c0c>] platform_drv_probe+0x60/0xac
[<c06f1abc>] driver_probe_device+0x214/0x2dc
[<c06f1c18>] __driver_attach+0x94/0xc0
[<c06efe2c>] bus_for_each_dev+0x90/0xa0
[<c06f1470>] driver_attach+0x28/0x30
[<c06f1030>] bus_add_driver+0x184/0x1ec
[<c06f2b74>] driver_register+0xb0/0xf0
[<c06f3b4c>] __platform_driver_register+0x40/0x54

Signed-off-by: Zumeng Chen <zumeng.chen@xxxxxxxxx>
Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/mfd/ti_am335x_tscadc.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

--- a/drivers/mfd/ti_am335x_tscadc.c
+++ b/drivers/mfd/ti_am335x_tscadc.c
@@ -227,14 +227,13 @@ static int ti_tscadc_probe(struct platfo
* The TSC_ADC_SS controller design assumes the OCP clock is
* at least 6x faster than the ADC clock.
*/
- clk = clk_get(&pdev->dev, "adc_tsc_fck");
+ clk = devm_clk_get(&pdev->dev, "adc_tsc_fck");
if (IS_ERR(clk)) {
dev_err(&pdev->dev, "failed to get TSC fck\n");
err = PTR_ERR(clk);
goto err_disable_clk;
}
clock_rate = clk_get_rate(clk);
- clk_put(clk);
tscadc->clk_div = clock_rate / ADC_CLK;

/* TSCADC_CLKDIV needs to be configured to the value minus 1 */