| Message ID | 20210211233744.3348384-1-dmitry.baryshkov@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | misc: fastrpc: restrict user apps from sending kernel RPC messages | expand |
On 2/11/21 3:37 PM, Dmitry Baryshkov wrote: > Verify that user applications are not using the kernel RPC message > handle to restrict them from directly attaching to guest OS on the > remote subsystem. This is a port of CVE-2019-2308 fix. > > Fixes: c68cfb718c8f ("misc: fastrpc: Add support for context Invoke method") > Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> > Cc: Jonathan Marek <jonathan@marek.ca> > Cc: stable@vger.kernel.org > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> > --- > drivers/misc/fastrpc.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c > index 815d01f785df..e7f3a22fdaa3 100644 > --- a/drivers/misc/fastrpc.c > +++ b/drivers/misc/fastrpc.c > @@ -948,6 +948,11 @@ static int fastrpc_internal_invoke(struct fastrpc_user *fl, u32 kernel, > if (!fl->cctx->rpdev) > return -EPIPE; > > + if (handle == FASTRPC_INIT_HANDLE && !kernel) { > + dev_warn(fl->sctx->dev, "user app trying to send a kernel RPC message (%d)\n", handle); rate limit so that userspace cannot flood kernel log? > + return -EPERM; > + } > + > ctx = fastrpc_context_alloc(fl, kernel, sc, args); > if (IS_ERR(ctx)) > return PTR_ERR(ctx); > -- ~Randy
diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c index 815d01f785df..e7f3a22fdaa3 100644 --- a/drivers/misc/fastrpc.c +++ b/drivers/misc/fastrpc.c @@ -948,6 +948,11 @@ static int fastrpc_internal_invoke(struct fastrpc_user *fl, u32 kernel, if (!fl->cctx->rpdev) return -EPIPE; + if (handle == FASTRPC_INIT_HANDLE && !kernel) { + dev_warn(fl->sctx->dev, "user app trying to send a kernel RPC message (%d)\n", handle); + return -EPERM; + } + ctx = fastrpc_context_alloc(fl, kernel, sc, args); if (IS_ERR(ctx)) return PTR_ERR(ctx);
Verify that user applications are not using the kernel RPC message handle to restrict them from directly attaching to guest OS on the remote subsystem. This is a port of CVE-2019-2308 fix. Fixes: c68cfb718c8f ("misc: fastrpc: Add support for context Invoke method") Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Cc: Jonathan Marek <jonathan@marek.ca> Cc: stable@vger.kernel.org Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> --- drivers/misc/fastrpc.c | 5 +++++ 1 file changed, 5 insertions(+) -- 2.30.0