busybox 1.19.3 cp bug w.r.t device files?

[Denys Vlasenko]

On Wed, Dec 21, 2011 at 2:38 PM, Joakim Tjernlund
<joakim.tjernlund at transmode.se> wrote:
> Denys Vlasenko <vda.linux at googlemail.com> wrote on 2011/12/21 13:08:30:
>>
>> On Wed, Dec 21, 2011 at 12:31 PM, Joakim Tjernlund
>> <joakim.tjernlund at transmode.se> wrote:
>> >
>> > Recently installed bb 1.19.3 (gentoo) on our ppc target. Today I discovered
>> > that cp vmlinux /dev/mtdblock5 dosn't work. The device file is removed and
>> > a new plain file is created instead.
>> > Feels like a bb bug, comments?
>>
>> config FEATURE_NON_POSIX_CP
>>         bool "Non-POSIX, but safer, copying to special nodes"
>>         default y
>>         help
>>           With this option, "cp file symlink" will delete symlink
>>           and create a regular file. This does not conform to POSIX,
>>           but prevents a symlink attack.
>>           Similarly, "cp file device" will not send file's data
>>           to the device. (To do that, use "cat file >device")
>
> Not 100% sure how to read this. I have CONFIG_FEATURE_NON_POSIX_CP=y
> already. Should I change to CONFIG_FEATURE_NON_POSIX_CP=n?

Yes. (however, I personally think it's better to use cat, not cp,
for the operation you are trying to perform)