| Message ID | HK0PR02MB36344D81C6E66666EB60849DB26E0@HK0PR02MB3634.apcprd02.prod.outlook.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v3] mtd: rawnand: atmel: fix possible object reference leak | expand |
Hi Wen, For the next version can you please post a series with the three commits which are fixing the same reference leak? No need to add a cover letter though. Wen Yang <yellowriver2010@hotmail.com> wrote on Tue, 5 Feb 2019 14:32:41 +0000: > of_find_device_by_node() takes a reference to the struct device > when it finds a match via get_device, there is no need to call > get_device() twice. > We also should make sure to drop the reference to the device > taken by of_find_device_by_node() on driver unbind. > > Fixes: f88fc122cc34 ("mtd: nand: Cleanup/rework the atmel_nand driver") > Signed-off-by: Wen Yang <yellowriver2010@hotmail.com> > Suggested-by: Boris Brezillon <bbrezillon@kernel.org> > Reviewed-by: Boris Brezillon <bbrezillon@kernel.org> > Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com> > Acked-by: Miquel Raynal <miquel.raynal@bootlin.com> > Cc: Tudor Ambarus <tudor.ambarus@microchip.com> > Cc: Boris Brezillon <bbrezillon@kernel.org> > Cc: Miquel Raynal <miquel.raynal@bootlin.com> > Cc: Richard Weinberger <richard@nod.at> > Cc: David Woodhouse <dwmw2@infradead.org> > Cc: Brian Norris <computersforpeace@gmail.com> > Cc: Marek Vasut <marek.vasut@gmail.com> > Cc: Nicolas Ferre <nicolas.ferre@microchip.com> > Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> > Cc: Ludovic Desroches <ludovic.desroches@microchip.com> > Cc: linux-mtd@lists.infradead.org > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-kernel@vger.kernel.org > --- > drivers/mtd/nand/raw/atmel/pmecc.c | 18 ++++++++++++++---- > 1 file changed, 14 insertions(+), 4 deletions(-) > > diff --git a/drivers/mtd/nand/raw/atmel/pmecc.c b/drivers/mtd/nand/raw/atmel/pmecc.c > index 555a74e..1477368 100644 > --- a/drivers/mtd/nand/raw/atmel/pmecc.c > +++ b/drivers/mtd/nand/raw/atmel/pmecc.c > @@ -876,16 +876,22 @@ static struct atmel_pmecc *atmel_pmecc_get_by_node(struct device *userdev, > { > struct platform_device *pdev; > struct atmel_pmecc *pmecc, **ptr; > + int ret; > > pdev = of_find_device_by_node(np); > - if (!pdev || !platform_get_drvdata(pdev)) > + if (!pdev) > return ERR_PTR(-EPROBE_DEFER); > + if (!platform_get_drvdata(pdev)) { > + ret = -EPROBE_DEFER; > + goto err_put_device; > + } > > ptr = devres_alloc(devm_atmel_pmecc_put, sizeof(*ptr), GFP_KERNEL); > - if (!ptr) > - return ERR_PTR(-ENOMEM); > + if (!ptr) { > + ret = -ENOMEM; > + goto err_put_device; > + } > > - get_device(&pdev->dev); > pmecc = platform_get_drvdata(pdev); I just realized in the three cases, a first call to platform_get_drvdata() is done to check if the returned pointer is valid, and then a second one is done to actually retrieve the pointer. Please avoid this repetition. Thanks, Miquèl
diff --git a/drivers/mtd/nand/raw/atmel/pmecc.c b/drivers/mtd/nand/raw/atmel/pmecc.c index 555a74e..1477368 100644 --- a/drivers/mtd/nand/raw/atmel/pmecc.c +++ b/drivers/mtd/nand/raw/atmel/pmecc.c @@ -876,16 +876,22 @@ static struct atmel_pmecc *atmel_pmecc_get_by_node(struct device *userdev, { struct platform_device *pdev; struct atmel_pmecc *pmecc, **ptr; + int ret; pdev = of_find_device_by_node(np); - if (!pdev || !platform_get_drvdata(pdev)) + if (!pdev) return ERR_PTR(-EPROBE_DEFER); + if (!platform_get_drvdata(pdev)) { + ret = -EPROBE_DEFER; + goto err_put_device; + } ptr = devres_alloc(devm_atmel_pmecc_put, sizeof(*ptr), GFP_KERNEL); - if (!ptr) - return ERR_PTR(-ENOMEM); + if (!ptr) { + ret = -ENOMEM; + goto err_put_device; + } - get_device(&pdev->dev); pmecc = platform_get_drvdata(pdev); *ptr = pmecc; @@ -893,6 +899,10 @@ static struct atmel_pmecc *atmel_pmecc_get_by_node(struct device *userdev, devres_add(userdev, ptr); return pmecc; + +err_put_device: + put_device(&pdev->dev); + return ERR_PTR(ret); } static const int atmel_pmecc_strengths[] = { 2, 4, 8, 12, 24, 32 };
of_find_device_by_node() takes a reference to the struct device when it finds a match via get_device, there is no need to call get_device() twice. We also should make sure to drop the reference to the device taken by of_find_device_by_node() on driver unbind. Fixes: f88fc122cc34 ("mtd: nand: Cleanup/rework the atmel_nand driver") Signed-off-by: Wen Yang <yellowriver2010@hotmail.com> Suggested-by: Boris Brezillon <bbrezillon@kernel.org> Reviewed-by: Boris Brezillon <bbrezillon@kernel.org> Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com> Acked-by: Miquel Raynal <miquel.raynal@bootlin.com> Cc: Tudor Ambarus <tudor.ambarus@microchip.com> Cc: Boris Brezillon <bbrezillon@kernel.org> Cc: Miquel Raynal <miquel.raynal@bootlin.com> Cc: Richard Weinberger <richard@nod.at> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Brian Norris <computersforpeace@gmail.com> Cc: Marek Vasut <marek.vasut@gmail.com> Cc: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Ludovic Desroches <ludovic.desroches@microchip.com> Cc: linux-mtd@lists.infradead.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org --- drivers/mtd/nand/raw/atmel/pmecc.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-)