| From 4380eba3cf1abb3a0abbe8b1ffc6f051381454eb Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Wed, 3 Mar 2021 16:57:35 +0100 |
| Subject: mtd: require write permissions for locking and badblock ioctls |
| MIME-Version: 1.0 |
| Content-Type: text/plain; charset=UTF-8 |
| Content-Transfer-Encoding: 8bit |
| |
| From: Michael Walle <michael@walle.cc> |
| |
| [ Upstream commit 1e97743fd180981bef5f01402342bb54bf1c6366 ] |
| |
| MEMLOCK, MEMUNLOCK and OTPLOCK modify protection bits. Thus require |
| write permission. Depending on the hardware MEMLOCK might even be |
| write-once, e.g. for SPI-NOR flashes with their WP# tied to GND. OTPLOCK |
| is always write-once. |
| |
| MEMSETBADBLOCK modifies the bad block table. |
| |
| Fixes: f7e6b19bc764 ("mtd: properly check all write ioctls for permissions") |
| Signed-off-by: Michael Walle <michael@walle.cc> |
| Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| Acked-by: Rafał Miłecki <rafal@milecki.pl> |
| Acked-by: Richard Weinberger <richard@nod.at> |
| Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> |
| Link: https://lore.kernel.org/linux-mtd/20210303155735.25887-1-michael@walle.cc |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/mtd/mtdchar.c | 8 ++++---- |
| 1 file changed, 4 insertions(+), 4 deletions(-) |
| |
| diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c |
| index 323035d4f2d0..688de663cabf 100644 |
| --- a/drivers/mtd/mtdchar.c |
| +++ b/drivers/mtd/mtdchar.c |
| @@ -651,16 +651,12 @@ static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg) |
| case MEMGETINFO: |
| case MEMREADOOB: |
| case MEMREADOOB64: |
| - case MEMLOCK: |
| - case MEMUNLOCK: |
| case MEMISLOCKED: |
| case MEMGETOOBSEL: |
| case MEMGETBADBLOCK: |
| - case MEMSETBADBLOCK: |
| case OTPSELECT: |
| case OTPGETREGIONCOUNT: |
| case OTPGETREGIONINFO: |
| - case OTPLOCK: |
| case ECCGETLAYOUT: |
| case ECCGETSTATS: |
| case MTDFILEMODE: |
| @@ -671,9 +667,13 @@ static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg) |
| /* "dangerous" commands */ |
| case MEMERASE: |
| case MEMERASE64: |
| + case MEMLOCK: |
| + case MEMUNLOCK: |
| + case MEMSETBADBLOCK: |
| case MEMWRITEOOB: |
| case MEMWRITEOOB64: |
| case MEMWRITE: |
| + case OTPLOCK: |
| if (!(file->f_mode & FMODE_WRITE)) |
| return -EPERM; |
| break; |
| -- |
| 2.30.2 |
| |