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author | Ekansh Gupta <quic_ekangupt@quicinc.com> | 2024-06-28 13:45:01 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-07-03 16:17:53 +0200 |
commit | bab2f5e8fd5d2f759db26b78d9db57412888f187 (patch) | |
tree | 63e5d5af7271ad5d612f8429ed68aab6f3d97081 | |
parent | misc: fastrpc: Fix ownership reassignment of remote heap (diff) | |
download | linux-bab2f5e8fd5d2f759db26b78d9db57412888f187.tar.xz linux-bab2f5e8fd5d2f759db26b78d9db57412888f187.zip |
misc: fastrpc: Restrict untrusted app to attach to privileged PD
Untrusted application with access to only non-secure fastrpc device
node can attach to root_pd or static PDs if it can make the respective
init request. This can cause problems as the untrusted application
can send bad requests to root_pd or static PDs. Add changes to reject
attach to privileged PDs if the request is being made using non-secure
fastrpc device node.
Fixes: 0871561055e6 ("misc: fastrpc: Add support for audiopd")
Cc: stable <stable@kernel.org>
Signed-off-by: Ekansh Gupta <quic_ekangupt@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20240628114501.14310-7-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/misc/fastrpc.c | 22 | ||||
-rw-r--r-- | include/uapi/misc/fastrpc.h | 3 |
2 files changed, 22 insertions, 3 deletions
diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c index 5680856c0fb8..a7a2bcedb37e 100644 --- a/drivers/misc/fastrpc.c +++ b/drivers/misc/fastrpc.c @@ -2087,6 +2087,16 @@ err_invoke: return err; } +static int is_attach_rejected(struct fastrpc_user *fl) +{ + /* Check if the device node is non-secure */ + if (!fl->is_secure_dev) { + dev_dbg(&fl->cctx->rpdev->dev, "untrusted app trying to attach to privileged DSP PD\n"); + return -EACCES; + } + return 0; +} + static long fastrpc_device_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -2099,13 +2109,19 @@ static long fastrpc_device_ioctl(struct file *file, unsigned int cmd, err = fastrpc_invoke(fl, argp); break; case FASTRPC_IOCTL_INIT_ATTACH: - err = fastrpc_init_attach(fl, ROOT_PD); + err = is_attach_rejected(fl); + if (!err) + err = fastrpc_init_attach(fl, ROOT_PD); break; case FASTRPC_IOCTL_INIT_ATTACH_SNS: - err = fastrpc_init_attach(fl, SENSORS_PD); + err = is_attach_rejected(fl); + if (!err) + err = fastrpc_init_attach(fl, SENSORS_PD); break; case FASTRPC_IOCTL_INIT_CREATE_STATIC: - err = fastrpc_init_create_static_process(fl, argp); + err = is_attach_rejected(fl); + if (!err) + err = fastrpc_init_create_static_process(fl, argp); break; case FASTRPC_IOCTL_INIT_CREATE: err = fastrpc_init_create_process(fl, argp); diff --git a/include/uapi/misc/fastrpc.h b/include/uapi/misc/fastrpc.h index f33d914d8f46..91583690bddc 100644 --- a/include/uapi/misc/fastrpc.h +++ b/include/uapi/misc/fastrpc.h @@ -8,11 +8,14 @@ #define FASTRPC_IOCTL_ALLOC_DMA_BUFF _IOWR('R', 1, struct fastrpc_alloc_dma_buf) #define FASTRPC_IOCTL_FREE_DMA_BUFF _IOWR('R', 2, __u32) #define FASTRPC_IOCTL_INVOKE _IOWR('R', 3, struct fastrpc_invoke) +/* This ioctl is only supported with secure device nodes */ #define FASTRPC_IOCTL_INIT_ATTACH _IO('R', 4) #define FASTRPC_IOCTL_INIT_CREATE _IOWR('R', 5, struct fastrpc_init_create) #define FASTRPC_IOCTL_MMAP _IOWR('R', 6, struct fastrpc_req_mmap) #define FASTRPC_IOCTL_MUNMAP _IOWR('R', 7, struct fastrpc_req_munmap) +/* This ioctl is only supported with secure device nodes */ #define FASTRPC_IOCTL_INIT_ATTACH_SNS _IO('R', 8) +/* This ioctl is only supported with secure device nodes */ #define FASTRPC_IOCTL_INIT_CREATE_STATIC _IOWR('R', 9, struct fastrpc_init_create_static) #define FASTRPC_IOCTL_MEM_MAP _IOWR('R', 10, struct fastrpc_mem_map) #define FASTRPC_IOCTL_MEM_UNMAP _IOWR('R', 11, struct fastrpc_mem_unmap) |