RE: [PATCH] usb: atm: don't use snprintf() for sysfs attrs

From: David Laight
Date: Tue Aug 25 2020 - 04:12:13 EST


From: Alex Dewar
> Sent: 24 August 2020 23:23
> kernel/cpu.c: don't use snprintf() for sysfs attrs
>
> As per the documentation (Documentation/filesystems/sysfs.rst),
> snprintf() should not be used for formatting values returned by sysfs.
>
> In all of these cases, sprintf() suffices as we know that the formatted
> strings will be less than PAGE_SIZE in length.

Hmmmm....
I much prefer to see bounded string ops.
sysfs really ought to be passing through the buffer length.
The buffer size should probably be SYSFS_BUF_LEN not PAGE_SIZE
(even it happens to typically be the same).
If PAGE_SIZE is big (or small) passing a 4k buffer may be
more appropriate than a PAGE_SIZE one.

David

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