diff options
| author | Dmitry Baryshkov <dmitry.baryshkov@linaro.org> | 2021-02-11 16:12:35 +0300 |
|---|---|---|
| committer | Dmitry Baryshkov <dmitry.baryshkov@linaro.org> | 2021-02-11 18:14:31 +0300 |
| commit | 7b0d53b236d92286e71c3a9f7dddcfdcf19cc16c (patch) | |
| tree | 8a5918ee4abc2a005605e644bdf446142c781b7d | |
| parent | d80d304b9370028e922292fc4e68a48c5ae0f563 (diff) | |
misc: fastrpc: restrict user apps from sending kernel RPC messages
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>
| -rw-r--r-- | drivers/misc/fastrpc.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c index f12e909034ac..20994dc6757a 100644 --- a/drivers/misc/fastrpc.c +++ b/drivers/misc/fastrpc.c @@ -950,6 +950,11 @@ 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); |