| Message ID | 20240211091633.4545-1-erick.archer@gmx.com (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | e395036504c4e19d15ba64543a4c3beca373f7a9 |
| Headers | show |
| Series | [v2] mtd: rawnand: Prefer struct_size over open coded arithmetic | expand |
On Sun, Feb 11, 2024 at 10:16:33AM +0100, Erick Archer wrote: > This is an effort to get rid of all multiplications from allocation > functions in order to prevent integer overflows [1]. > > As the "chip" variable is a pointer to "struct mtk_nfc_nand_chip" and > this structure ends in a flexible array: > > struct mtk_nfc_nand_chip { > [...] > u8 sels[] __counted_by(nsels); > }; > > the preferred way in the kernel is to use the struct_size() helper to > do the arithmetic instead of the argument "size + count * size" in the > devm_kzalloc() function. > > This way, the code is more readable and safer. > > Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1] > Link: https://github.com/KSPP/linux/issues/160 [2] > Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> > Signed-off-by: Erick Archer <erick.archer@gmx.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Best regards Uwe
Il 11/02/24 10:16, Erick Archer ha scritto: > This is an effort to get rid of all multiplications from allocation > functions in order to prevent integer overflows [1]. > > As the "chip" variable is a pointer to "struct mtk_nfc_nand_chip" and > this structure ends in a flexible array: > > struct mtk_nfc_nand_chip { > [...] > u8 sels[] __counted_by(nsels); > }; > > the preferred way in the kernel is to use the struct_size() helper to > do the arithmetic instead of the argument "size + count * size" in the > devm_kzalloc() function. > > This way, the code is more readable and safer. > > Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1] > Link: https://github.com/KSPP/linux/issues/160 [2] > Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> > Signed-off-by: Erick Archer <erick.archer@gmx.com> Just noticed that there was a v2 already addressing the commit description issue. Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
On 11/02/2024 10:16, Erick Archer wrote: > This is an effort to get rid of all multiplications from allocation > functions in order to prevent integer overflows [1]. > > As the "chip" variable is a pointer to "struct mtk_nfc_nand_chip" and > this structure ends in a flexible array: > > struct mtk_nfc_nand_chip { > [...] > u8 sels[] __counted_by(nsels); > }; > > the preferred way in the kernel is to use the struct_size() helper to > do the arithmetic instead of the argument "size + count * size" in the > devm_kzalloc() function. > > This way, the code is more readable and safer. > > Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1] > Link: https://github.com/KSPP/linux/issues/160 [2] > Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> > Signed-off-by: Erick Archer <erick.archer@gmx.com> Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com> > --- > Changes in v2: > - Add the "Reviewed-by:" tag. > - Fix a spelling error in the commit message. Change "more safer" for > "safer" (Uwe Kleine-König) > --- > drivers/mtd/nand/raw/mtk_nand.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/mtd/nand/raw/mtk_nand.c b/drivers/mtd/nand/raw/mtk_nand.c > index 60198e33d2d5..17477bb2d48f 100644 > --- a/drivers/mtd/nand/raw/mtk_nand.c > +++ b/drivers/mtd/nand/raw/mtk_nand.c > @@ -1356,7 +1356,7 @@ static int mtk_nfc_nand_chip_init(struct device *dev, struct mtk_nfc *nfc, > return -EINVAL; > } > > - chip = devm_kzalloc(dev, sizeof(*chip) + nsels * sizeof(u8), > + chip = devm_kzalloc(dev, struct_size(chip, sels, nsels), > GFP_KERNEL); > if (!chip) > return -ENOMEM; > -- > 2.25.1 >
On Sun, 2024-02-11 at 09:16:33 UTC, Erick Archer wrote: > This is an effort to get rid of all multiplications from allocation > functions in order to prevent integer overflows [1]. > > As the "chip" variable is a pointer to "struct mtk_nfc_nand_chip" and > this structure ends in a flexible array: > > struct mtk_nfc_nand_chip { > [...] > u8 sels[] __counted_by(nsels); > }; > > the preferred way in the kernel is to use the struct_size() helper to > do the arithmetic instead of the argument "size + count * size" in the > devm_kzalloc() function. > > This way, the code is more readable and safer. > > Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1] > Link: https://github.com/KSPP/linux/issues/160 [2] > Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> > Signed-off-by: Erick Archer <erick.archer@gmx.com> > Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> > Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> > Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com> Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next, thanks. Miquel
diff --git a/drivers/mtd/nand/raw/mtk_nand.c b/drivers/mtd/nand/raw/mtk_nand.c index 60198e33d2d5..17477bb2d48f 100644 --- a/drivers/mtd/nand/raw/mtk_nand.c +++ b/drivers/mtd/nand/raw/mtk_nand.c @@ -1356,7 +1356,7 @@ static int mtk_nfc_nand_chip_init(struct device *dev, struct mtk_nfc *nfc, return -EINVAL; } - chip = devm_kzalloc(dev, sizeof(*chip) + nsels * sizeof(u8), + chip = devm_kzalloc(dev, struct_size(chip, sels, nsels), GFP_KERNEL); if (!chip) return -ENOMEM;
This is an effort to get rid of all multiplications from allocation functions in order to prevent integer overflows [1]. As the "chip" variable is a pointer to "struct mtk_nfc_nand_chip" and this structure ends in a flexible array: struct mtk_nfc_nand_chip { [...] u8 sels[] __counted_by(nsels); }; the preferred way in the kernel is to use the struct_size() helper to do the arithmetic instead of the argument "size + count * size" in the devm_kzalloc() function. This way, the code is more readable and safer. Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1] Link: https://github.com/KSPP/linux/issues/160 [2] Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Erick Archer <erick.archer@gmx.com> --- Changes in v2: - Add the "Reviewed-by:" tag. - Fix a spelling error in the commit message. Change "more safer" for "safer" (Uwe Kleine-König) --- drivers/mtd/nand/raw/mtk_nand.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.25.1