On 09/14/16 at 09:23am, Micka?l Sala?n wrote:
> This fix a pointer leak when an unprivileged eBPF program read a pointer
> value from the context. Even if is_valid_access() returns a pointer
> type, the eBPF verifier replace it with UNKNOWN_VALUE. The register
> value containing an address is then allowed to leak. Moreover, this
> prevented unprivileged eBPF programs to use functions with (legitimate)
> pointer arguments.
>
> This bug was not a problem until now because the only unprivileged eBPF
> program allowed is of type BPF_PROG_TYPE_SOCKET_FILTER and all the types
> from its context are UNKNOWN_VALUE.
>
> Signed-off-by: Micka?l Sala?n <[email protected]>
> Fixes: 969bf05eb3ce ("bpf: direct packet access")
> Cc: Alexei Starovoitov <[email protected]>
> Cc: Daniel Borkmann <[email protected]>
Can you post this fix separately? It's valid and needed outside of the
scope of this series.
On 10/19/2016 04:54 PM, Thomas Graf wrote:
> On 09/14/16 at 09:23am, Micka?l Sala?n wrote:
>> This fix a pointer leak when an unprivileged eBPF program read a pointer
>> value from the context. Even if is_valid_access() returns a pointer
>> type, the eBPF verifier replace it with UNKNOWN_VALUE. The register
>> value containing an address is then allowed to leak. Moreover, this
>> prevented unprivileged eBPF programs to use functions with (legitimate)
>> pointer arguments.
>>
>> This bug was not a problem until now because the only unprivileged eBPF
>> program allowed is of type BPF_PROG_TYPE_SOCKET_FILTER and all the types
>> from its context are UNKNOWN_VALUE.
>>
>> Signed-off-by: Micka?l Sala?n <[email protected]>
>> Fixes: 969bf05eb3ce ("bpf: direct packet access")
>> Cc: Alexei Starovoitov <[email protected]>
>> Cc: Daniel Borkmann <[email protected]>
>
> Can you post this fix separately? It's valid and needed outside of the
> scope of this series.
Yes, that one was already merged:
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=1955351da41caa1dbf4139191358fed84909d64b