From: Wolfgang Bumiller <w.bumil...@proxmox.com>
Date: Thu, 20 Apr 2017 14:08:26 +0200
> Policing filters do not use the TCA_ACT_* enum and the tb[]
> nlattr array in tcf_action_init_1() doesn't get filled for
> them so we should not try to look for a TCA_ACT_COOKIE
> attribute in the then uninitialized array.
> The error handling in cookie allocation then calls
> tcf_hash_release() leading to invalid memory access later
> on.
> Additionally, if cookie allocation fails after an already
> existing non-policing filter has successfully been changed,
> tcf_action_release() should not be called, also we would
> have to roll back the changes in the error handling, so
> instead we now allocate the cookie early and assign it on
> success at the end.
>
> CVE-2017-7979
> Fixes: 1045ba77a596 ("net sched actions: Add support for user cookies")
> Signed-off-by: Wolfgang Bumiller <w.bumil...@proxmox.com>
> Acked-by: Jamal Hadi Salim <j...@mojatatu.com>
Applied and queued up for -stable.
