2024-03-26 01:56:20

by Gustavo A. R. Silva

Subject: [PATCH][next] firewire: Annotate struct fw_iso_packet with __counted_by()

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).

Signed-off-by: Gustavo A. R. Silva <[email protected]>
---
include/linux/firewire.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/linux/firewire.h b/include/linux/firewire.h
index dd9f2d765e68..00abe0e5d602 100644
--- a/include/linux/firewire.h
+++ b/include/linux/firewire.h
@@ -463,7 +463,8 @@ struct fw_iso_packet {
u32 tag:2; /* tx: Tag in packet header */
u32 sy:4; /* tx: Sy in packet header */
u32 header_length:8; /* Length of immediate header */
- u32 header[]; /* tx: Top of 1394 isoch. data_block */
+ /* tx: Top of 1394 isoch. data_block */
+ u32 header[] __counted_by(header_length);
};

#define FW_ISO_CONTEXT_TRANSMIT 0
--
2.34.1

2024-03-26 04:19:56

by Takashi Sakamoto

Subject: Re: [PATCH][next] firewire: Annotate struct fw_iso_packet with __counted_by()

Hi,

On Mon, Mar 25, 2024 at 07:56:10PM -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).
>
> Signed-off-by: Gustavo A. R. Silva <[email protected]>
> ---
> include/linux/firewire.h | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)

Applied to for-next branch, since it demands no code changes to the other
subsystem.


Thanks

Takashi Sakamoto