| Message ID | 20210324230036.GA67851@embeddedor (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [next] SCSI: fusion: mpi_ioc.h: Replace one-element array with flexible-array member | expand |
On Wed, 24 Mar 2021 18:00:36 -0500, Gustavo A. R. Silva wrote: > There is a regular need in the kernel to provide a way to declare having > a dynamically sized set of trailing elements in a structure. Kernel code > should always use “flexible array members”[1] for these cases. The older > style of one-element or zero-length arrays should no longer be used[2]. > > Also, this helps with the ongoing efforts to enable -Warray-bounds by > fixing the following warning: > > [...] Applied to 5.13/scsi-queue, thanks! [1/1] SCSI: fusion: mpi_ioc.h: Replace one-element array with flexible-array member https://git.kernel.org/mkp/scsi/c/ed46ccc7fe76
diff --git a/drivers/message/fusion/lsi/mpi_ioc.h b/drivers/message/fusion/lsi/mpi_ioc.h index c249f2994fc1..1534460fd5b1 100644 --- a/drivers/message/fusion/lsi/mpi_ioc.h +++ b/drivers/message/fusion/lsi/mpi_ioc.h @@ -448,7 +448,7 @@ typedef struct _MSG_EVENT_NOTIFY_REPLY U32 IOCLogInfo; /* 10h */ U32 Event; /* 14h */ U32 EventContext; /* 18h */ - U32 Data[1]; /* 1Ch */ + U32 Data[]; /* 1Ch */ } MSG_EVENT_NOTIFY_REPLY, MPI_POINTER PTR_MSG_EVENT_NOTIFY_REPLY, EventNotificationReply_t, MPI_POINTER pEventNotificationReply_t;
There is a regular need in the kernel to provide a way to declare having a dynamically sized set of trailing elements in a structure. Kernel code should always use “flexible array members”[1] for these cases. The older style of one-element or zero-length arrays should no longer be used[2]. Also, this helps with the ongoing efforts to enable -Warray-bounds by fixing the following warning: drivers/message/fusion/mptbase.c: In function ‘mptbase_reply’: drivers/message/fusion/mptbase.c:7747:62: warning: array subscript 1 is above array bounds of ‘U32[1]’ {aka ‘unsigned int[1]’} [-Warray-bounds] 7747 | ioc->events[idx].data[ii] = le32_to_cpu(pEventReply->Data[ii]); ./include/uapi/linux/byteorder/little_endian.h:34:51: note: in definition of macro ‘__le32_to_cpu’ 34 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x)) | ^ drivers/message/fusion/mptbase.c:7747:33: note: in expansion of macro ‘le32_to_cpu’ 7747 | ioc->events[idx].data[ii] = le32_to_cpu(pEventReply->Data[ii]); | [1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://www.kernel.org/doc/html/v5.10/process/deprecated.html#zero-length-and-one-element-arrays Link: https://github.com/KSPP/linux/issues/79 Link: https://github.com/KSPP/linux/issues/109 Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> --- drivers/message/fusion/lsi/mpi_ioc.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)