On Mon, Jan 11, 2021 at 09:36:16AM -0800, Jakub Kicinski wrote: > On Mon, 11 Jan 2021 14:00:42 +0100 Greg Kroah-Hartman wrote: > > From: Petr Machata <me@xxxxxxxxxxxx> > > > > [ Upstream commit 826f328e2b7e8854dd42ea44e6519cd75018e7b1 ] > > > > DCB uses the same handler function for both RTM_GETDCB and RTM_SETDCB > > messages. dcb_doit() bounces RTM_SETDCB mesasges if the user does not have > > the CAP_NET_ADMIN capability. > > > > However, the operation to be performed is not decided from the DCB message > > type, but from the DCB command. Thus DCB_CMD_*_GET commands are used for > > reading DCB objects, the corresponding SET and DEL commands are used for > > manipulation. > > > > The assumption is that set-like commands will be sent via an RTM_SETDCB > > message, and get-like ones via RTM_GETDCB. However, this assumption is not > > enforced. > > > > It is therefore possible to manipulate DCB objects without CAP_NET_ADMIN > > capability by sending the corresponding command in an RTM_GETDCB message. > > That is a bug. Fix it by validating the type of the request message against > > the type used for the response. > > > > Fixes: 2f90b8657ec9 ("ixgbe: this patch adds support for DCB to the kernel and ixgbe driver") > > Signed-off-by: Petr Machata <me@xxxxxxxxxxxx> > > Link: https://lore.kernel.org/r/a2a9b88418f3a58ef211b718f2970128ef9e3793.1608673640.git.me@xxxxxxxxxxxx > > Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> > > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > > Unfortunately we need to call backsies on this one. > > A fix up was just posted: > > https://patchwork.kernel.org/project/netdevbpf/patch/a3edcfda0825f2aa2591801c5232f2bbf2d8a554.1610384801.git.me@xxxxxxxxxxxx/ > > I'll resend both in the next submission. No worries, thanks for letting me know, I've now dropped it from all stable tree queues. thanks, greg k-h