| Message ID | ZSRw6RNi3Crhd32H@work (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [next] soc: qcom: apr: Add __counted_by for struct apr_rx_buf and use struct_size() | expand |
On Mon, Oct 09, 2023 at 03:30:17PM -0600, Gustavo A. R. Silva wrote: > Prepare for the coming implementation by GCC and Clang of the __counted_by > attribute. Flexible array members annotated with __counted_by can have > their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for > array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family > functions). > > While there, use struct_size() helper, instead of the open-coded > version, to calculate the size for the allocation of the whole > flexible structure, including of course, the flexible-array member. > > This code was found with the help of Coccinelle, and audited and > fixed manually. > > Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Yup, looks right. Reviewed-by: Kees Cook <keescook@chromium.org>
On Mon, Oct 9, 2023 at 2:30 PM Gustavo A. R. Silva <gustavoars@kernel.org> wrote: > > Prepare for the coming implementation by GCC and Clang of the __counted_by > attribute. Flexible array members annotated with __counted_by can have > their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for > array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family > functions). > > While there, use struct_size() helper, instead of the open-coded > version, to calculate the size for the allocation of the whole > flexible structure, including of course, the flexible-array member. > > This code was found with the help of Coccinelle, and audited and > fixed manually. > > Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Excited for __counted_by to land! This looks right. Reviewed-by: Justin Stitt <justinstitt@google.com> > --- > drivers/soc/qcom/apr.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/soc/qcom/apr.c b/drivers/soc/qcom/apr.c > index 30f81d6d9d9d..1f8b315576a4 100644 > --- a/drivers/soc/qcom/apr.c > +++ b/drivers/soc/qcom/apr.c > @@ -41,7 +41,7 @@ struct packet_router { > struct apr_rx_buf { > struct list_head node; > int len; > - uint8_t buf[]; > + uint8_t buf[] __counted_by(len); > }; > > /** > @@ -171,7 +171,7 @@ static int apr_callback(struct rpmsg_device *rpdev, void *buf, > return -EINVAL; > } > > - abuf = kzalloc(sizeof(*abuf) + len, GFP_ATOMIC); > + abuf = kzalloc(struct_size(abuf, buf, len), GFP_ATOMIC); > if (!abuf) > return -ENOMEM; > > -- > 2.34.1 > >
On Mon, Oct 09, 2023 at 03:30:17PM -0600, Gustavo A. R. Silva wrote: > Prepare for the coming implementation by GCC and Clang of the __counted_by > attribute. Flexible array members annotated with __counted_by can have > their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for > array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family > functions). > > While there, use struct_size() helper, instead of the open-coded > version, to calculate the size for the allocation of the whole > flexible structure, including of course, the flexible-array member. > > This code was found with the help of Coccinelle, and audited and > fixed manually. > > Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Applied, thanks. > --- > drivers/soc/qcom/apr.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/soc/qcom/apr.c b/drivers/soc/qcom/apr.c > index 30f81d6d9d9d..1f8b315576a4 100644 > --- a/drivers/soc/qcom/apr.c > +++ b/drivers/soc/qcom/apr.c > @@ -41,7 +41,7 @@ struct packet_router { > struct apr_rx_buf { > struct list_head node; > int len; > - uint8_t buf[]; > + uint8_t buf[] __counted_by(len); > }; > > /** > @@ -171,7 +171,7 @@ static int apr_callback(struct rpmsg_device *rpdev, void *buf, > return -EINVAL; > } > > - abuf = kzalloc(sizeof(*abuf) + len, GFP_ATOMIC); > + abuf = kzalloc(struct_size(abuf, buf, len), GFP_ATOMIC); > if (!abuf) > return -ENOMEM; > > -- > 2.34.1 >
diff --git a/drivers/soc/qcom/apr.c b/drivers/soc/qcom/apr.c index 30f81d6d9d9d..1f8b315576a4 100644 --- a/drivers/soc/qcom/apr.c +++ b/drivers/soc/qcom/apr.c @@ -41,7 +41,7 @@ struct packet_router { struct apr_rx_buf { struct list_head node; int len; - uint8_t buf[]; + uint8_t buf[] __counted_by(len); }; /** @@ -171,7 +171,7 @@ static int apr_callback(struct rpmsg_device *rpdev, void *buf, return -EINVAL; } - abuf = kzalloc(sizeof(*abuf) + len, GFP_ATOMIC); + abuf = kzalloc(struct_size(abuf, buf, len), GFP_ATOMIC); if (!abuf) return -ENOMEM;
Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). While there, use struct_size() helper, instead of the open-coded version, to calculate the size for the allocation of the whole flexible structure, including of course, the flexible-array member. This code was found with the help of Coccinelle, and audited and fixed manually. Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> --- drivers/soc/qcom/apr.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)