2020-07-25 06:31:34

by Wei Yongjun

Subject: [PATCH -next] mtd: fix missing unlock on error in mtdchar_compat_ioctl()

Add the missing unlock before return from function mtdchar_compat_ioctl()
in the error handling case.

Fixes: 210bec567936 ("mtd: properly check all write ioctls for permissions")
Reported-by: Hulk Robot <[email protected]>
Signed-off-by: Wei Yongjun <[email protected]>
---
drivers/mtd/mtdchar.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
index 52c120f9fb0d..b40f46a43fc6 100644
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -1064,8 +1064,10 @@ static long mtdchar_compat_ioctl(struct file *file, unsigned int cmd,
struct mtd_oob_buf32 buf;
struct mtd_oob_buf32 __user *buf_user = argp;

- if (!(file->f_mode & FMODE_WRITE))
- return -EPERM;
+ if (!(file->f_mode & FMODE_WRITE)) {
+ ret = -EPERM;
+ break;
+ }

if (copy_from_user(&buf, argp, sizeof(buf)))
ret = -EFAULT;

2020-07-25 06:37:35

by Greg Kroah-Hartman

Subject: Re: [PATCH -next] mtd: fix missing unlock on error in mtdchar_compat_ioctl()

On Sat, Jul 25, 2020 at 06:34:16AM +0000, Wei Yongjun wrote:
> Add the missing unlock before return from function mtdchar_compat_ioctl()
> in the error handling case.
>
> Fixes: 210bec567936 ("mtd: properly check all write ioctls for permissions")
> Reported-by: Hulk Robot <[email protected]>
> Signed-off-by: Wei Yongjun <[email protected]>
> ---
> drivers/mtd/mtdchar.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
> index 52c120f9fb0d..b40f46a43fc6 100644
> --- a/drivers/mtd/mtdchar.c
> +++ b/drivers/mtd/mtdchar.c
> @@ -1064,8 +1064,10 @@ static long mtdchar_compat_ioctl(struct file *file, unsigned int cmd,
> struct mtd_oob_buf32 buf;
> struct mtd_oob_buf32 __user *buf_user = argp;
>
> - if (!(file->f_mode & FMODE_WRITE))
> - return -EPERM;
> + if (!(file->f_mode & FMODE_WRITE)) {
> + ret = -EPERM;
> + break;
> + }
>
> if (copy_from_user(&buf, argp, sizeof(buf)))
> ret = -EFAULT;
>
>
>

I think Richard already resolved this in his tree, but I could be wrong.

And nice detection by your bot, that's good to see.

thanks,

greg k-h

2020-07-25 08:16:01

by Richard Weinberger

Subject: Re: [PATCH -next] mtd: fix missing unlock on error in mtdchar_compat_ioctl()

----- Ursprüngliche Mail -----
> Von: "Greg Kroah-Hartman" <[email protected]>
> An: "Wei Yongjun" <[email protected]>
> CC: "Miquel Raynal" <[email protected]>, "richard" <[email protected]>, "Vignesh Raghavendra" <[email protected]>,
> "linux-mtd" <[email protected]>, "linux-kernel" <[email protected]>, "kernel-janitors"
> <[email protected]>, "Hulk Robot" <[email protected]>
> Gesendet: Samstag, 25. Juli 2020 08:37:01
> Betreff: Re: [PATCH -next] mtd: fix missing unlock on error in mtdchar_compat_ioctl()
> I think Richard already resolved this in his tree, but I could be wrong.

Yes, fixed in git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git mtd/fixes
and should be visible in linux-next very soon.

> And nice detection by your bot, that's good to see.

Yeah, good to see that such issues are being detected automatically.

Thanks,
//richard