On Sun, Mar 11, 2018 at 09:06:10PM -0500, Larry Finger wrote: > On 03/11/2018 08:43 PM, Tobin C. Harding wrote: > >The kernel would like to have all stack VLA usage removed[1]. rsi uses > >a VLA based on 'blksize'. Elsewhere in the SDIO code maximum block size > >is defined using a magic number. We can use a pre-processor defined > >constant and declare the array to maximum size. We add a check before > >accessing the array in case of programmer error. > > > >[1]: https://lkml.org/lkml/2018/3/7/621 > > > >Signed-off-by: Tobin C. Harding <me@xxxxxxxx> > >--- > > > >RESEND: add wireless mailing list to CC's (requested by Kalle) > > > > drivers/net/wireless/rsi/rsi_91x_hal.c | 13 +++++++------ > > drivers/net/wireless/rsi/rsi_91x_sdio.c | 9 +++++++-- > > 2 files changed, 14 insertions(+), 8 deletions(-) > > > >diff --git a/drivers/net/wireless/rsi/rsi_91x_hal.c b/drivers/net/wireless/rsi/rsi_91x_hal.c > >index 1176de646942..839ebdd602df 100644 > >--- a/drivers/net/wireless/rsi/rsi_91x_hal.c > >+++ b/drivers/net/wireless/rsi/rsi_91x_hal.c > >@@ -641,7 +641,7 @@ static int ping_pong_write(struct rsi_hw *adapter, u8 cmd, u8 *addr, u32 size) > > u32 cmd_addr; > > u16 cmd_resp, cmd_req; > > u8 *str; > >- int status; > >+ int status, ret; > > if (cmd == PING_WRITE) { > > cmd_addr = PING_BUFFER_ADDRESS; > >@@ -655,12 +655,13 @@ static int ping_pong_write(struct rsi_hw *adapter, u8 cmd, u8 *addr, u32 size) > > str = "PONG_VALID"; > > } > >- status = hif_ops->load_data_master_write(adapter, cmd_addr, size, > >+ ret = hif_ops->load_data_master_write(adapter, cmd_addr, size, > > block_size, addr); > >- if (status) { > >- rsi_dbg(ERR_ZONE, "%s: Unable to write blk at addr %0x\n", > >- __func__, *addr); > >- return status; > >+ if (ret) { > >+ if (ret != -EINVAL) > >+ rsi_dbg(ERR_ZONE, "%s: Unable to write blk at addr %0x\n", > >+ __func__, *addr); > >+ return ret; > > } > > status = bl_cmd(adapter, cmd_req, cmd_resp, str); > >diff --git a/drivers/net/wireless/rsi/rsi_91x_sdio.c b/drivers/net/wireless/rsi/rsi_91x_sdio.c > >index b0cf41195051..b766578b591a 100644 > >--- a/drivers/net/wireless/rsi/rsi_91x_sdio.c > >+++ b/drivers/net/wireless/rsi/rsi_91x_sdio.c > >@@ -20,6 +20,8 @@ > > #include "rsi_common.h" > > #include "rsi_hal.h" > >+#define RSI_MAX_BLOCK_SIZE 256 > >+ > > /** > > * rsi_sdio_set_cmd52_arg() - This function prepares cmd 52 read/write arg. > > * @rw: Read/write > >@@ -362,7 +364,7 @@ static int rsi_setblocklength(struct rsi_hw *adapter, u32 length) > > rsi_dbg(INIT_ZONE, "%s: Setting the block length\n", __func__); > > status = sdio_set_block_size(dev->pfunction, length); > >- dev->pfunction->max_blksize = 256; > >+ dev->pfunction->max_blksize = RSI_MAX_BLOCK_SIZE; > > adapter->block_size = dev->pfunction->max_blksize; > > rsi_dbg(INFO_ZONE, > >@@ -567,9 +569,12 @@ static int rsi_sdio_load_data_master_write(struct rsi_hw *adapter, > > { > > u32 num_blocks, offset, i; > > u16 msb_address, lsb_address; > >- u8 temp_buf[block_size]; > >+ u8 temp_buf[RSI_MAX_BLOCK_SIZE]; > > int status; > >+ if (block_size > RSI_MAX_BLOCK_SIZE) > >+ return -EINVAL; > >+ > > num_blocks = instructions_sz / block_size; > > msb_address = base_address >> 16; > > I am not giving this patch a negative review, but my solution to the same > problem has been to change the on-stack array into a u8 pointer, use > kmalloc() to assign the space, and then free that space at the end. That way > large stack allocations are avoided, with a minimum of changes. Your idea is better Larry, have you got a patch done already or do you want me to knock one up? thanks, Tobin.
