[PATCH v2 0/2] meson-nand: two small memory related fixes

[PATCH v2 0/2] meson-nand: two small memory related fixes

[Martin Blumenstingl]

While trying to add support for older Meson SoCs to the meson-nand
driver I was experiencing a crash in meson_nfc_read_buf(). While trying
to find out why that happened I inspected the code in that function and
found that there's:
- a missing check on the return value of a kzalloc() call
- a potential memory leak in it

Both fixes have nothing to do with my original crash (for which I'll
open a separate thread).


Changes since v1:
- collected Liang's Acked-by's (thank you!)
- rebased on top of v5.1-rc1


Martin Blumenstingl (2):
  mtd: rawnand: meson: add missing ENOMEM check in meson_nfc_read_buf()
  mtd: rawnand: meson: fix a potential memory leak in meson_nfc_read_buf

 drivers/mtd/nand/raw/meson_nand.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

-- 
2.21.0


_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic

[PATCH v2 1/2] mtd: rawnand: meson: add missing ENOMEM check in meson_nfc_read_buf()

[Martin Blumenstingl]

kzalloc() can return NULL if memory could not be allocated. Check the
return value of the kzalloc() call in meson_nfc_read_buf() to make it
consistent with other memory allocations within the meson_nand driver.

Fixes: 8fae856c53500a ("mtd: rawnand: meson: add support for Amlogic NAND flash controller")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Liang Yang <liang.yang@amlogic.com>
---
 drivers/mtd/nand/raw/meson_nand.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/mtd/nand/raw/meson_nand.c b/drivers/mtd/nand/raw/meson_nand.c
index 3e8aa71407b5..a1d8506b61c7 100644
--- a/drivers/mtd/nand/raw/meson_nand.c
+++ b/drivers/mtd/nand/raw/meson_nand.c
@@ -528,6 +528,9 @@ static int meson_nfc_read_buf(struct nand_chip *nand, u8 *buf, int len)
 	u8 *info;
 
 	info = kzalloc(PER_INFO_BYTE, GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
 	ret = meson_nfc_dma_buffer_setup(nand, buf, len, info,
 					 PER_INFO_BYTE, DMA_FROM_DEVICE);
 	if (ret)
-- 
2.21.0


_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic

[PATCH v2 2/2] mtd: rawnand: meson: fix a potential memory leak in meson_nfc_read_buf

[Martin Blumenstingl]

meson_nfc_dma_buffer_setup() is called with the "info" buffer which is
allocated a few lines before using kzalloc(). If
meson_nfc_dma_buffer_setup() fails we need to free the allocated "info"
buffer instead of only freeing it upon success.

Fixes: 8fae856c53500a ("mtd: rawnand: meson: add support for Amlogic NAND flash controller")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Liang Yang <liang.yang@amlogic.com>
---
 drivers/mtd/nand/raw/meson_nand.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/nand/raw/meson_nand.c b/drivers/mtd/nand/raw/meson_nand.c
index a1d8506b61c7..38db4fd61459 100644
--- a/drivers/mtd/nand/raw/meson_nand.c
+++ b/drivers/mtd/nand/raw/meson_nand.c
@@ -534,7 +534,7 @@ static int meson_nfc_read_buf(struct nand_chip *nand, u8 *buf, int len)
 	ret = meson_nfc_dma_buffer_setup(nand, buf, len, info,
 					 PER_INFO_BYTE, DMA_FROM_DEVICE);
 	if (ret)
-		return ret;
+		goto out;
 
 	cmd = NFC_CMD_N2M | (len & GENMASK(5, 0));
 	writel(cmd, nfc->reg_base + NFC_REG_CMD);
@@ -542,6 +542,8 @@ static int meson_nfc_read_buf(struct nand_chip *nand, u8 *buf, int len)
 	meson_nfc_drain_cmd(nfc);
 	meson_nfc_wait_cmd_finish(nfc, 1000);
 	meson_nfc_dma_buffer_release(nand, len, PER_INFO_BYTE, DMA_FROM_DEVICE);
+
+out:
 	kfree(info);
 
 	return ret;
-- 
2.21.0


_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic

Re: [PATCH v2 1/2] mtd: rawnand: meson: add missing ENOMEM check in meson_nfc_read_buf()

[Kevin Hilman]

Martin Blumenstingl <martin.blumenstingl@googlemail.com> writes:

> kzalloc() can return NULL if memory could not be allocated. Check the
> return value of the kzalloc() call in meson_nfc_read_buf() to make it
> consistent with other memory allocations within the meson_nand driver.
>
> Fixes: 8fae856c53500a ("mtd: rawnand: meson: add support for Amlogic NAND flash controller")
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> Acked-by: Liang Yang <liang.yang@amlogic.com>

Reviewed-by: Kevin Hilman <khilman@baylibre.com>

_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic

Re: [PATCH v2 2/2] mtd: rawnand: meson: fix a potential memory leak in meson_nfc_read_buf

[Kevin Hilman]

Martin Blumenstingl <martin.blumenstingl@googlemail.com> writes:

> meson_nfc_dma_buffer_setup() is called with the "info" buffer which is
> allocated a few lines before using kzalloc(). If
> meson_nfc_dma_buffer_setup() fails we need to free the allocated "info"
> buffer instead of only freeing it upon success.
>
> Fixes: 8fae856c53500a ("mtd: rawnand: meson: add support for Amlogic NAND flash controller")
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> Acked-by: Liang Yang <liang.yang@amlogic.com>

Reviewed-by: Kevin Hilman <khilman@baylibre.com>

_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic

Re: [PATCH v2 0/2] meson-nand: two small memory related fixes

[Miquel Raynal]

Hi Martin,

Martin Blumenstingl <martin.blumenstingl@googlemail.com> wrote on Mon,
18 Mar 2019 21:47:20 +0100:

> While trying to add support for older Meson SoCs to the meson-nand
> driver I was experiencing a crash in meson_nfc_read_buf(). While trying
> to find out why that happened I inspected the code in that function and
> found that there's:
> - a missing check on the return value of a kzalloc() call
> - a potential memory leak in it
> 
> Both fixes have nothing to do with my original crash (for which I'll
> open a separate thread).
> 
> 
> Changes since v1:
> - collected Liang's Acked-by's (thank you!)
> - rebased on top of v5.1-rc1
> 
> 
> Martin Blumenstingl (2):
>   mtd: rawnand: meson: add missing ENOMEM check in meson_nfc_read_buf()
>   mtd: rawnand: meson: fix a potential memory leak in meson_nfc_read_buf
> 
>  drivers/mtd/nand/raw/meson_nand.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 


Applied to git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git
on nand/next.


Thanks,
Miquèl

_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic