lkml.org 
[lkml]   [2021]   [Jun]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v3] rtw_security: fix cast to restricted __le32
On Sat, Jun 19, 2021 at 02:17:51AM +0800, Jhih-Ming Huang wrote:
> This patch fixes the sparse warning of fix cast to restricted __le32.
>
> There was a change for replacing private CRC-32 routines with in kernel
> ones.
> However, the author used le32_to_cpu to convert crc32_le(), and we
> should cpu_to_le32.
>
> Ths commit also fixes the payload checking by memcmp instead of checking element
> by element.
>
> Signed-off-by: Jhih-Ming Huang <fbihjmeric@gmail.com>
> ---
> drivers/staging/rtl8723bs/core/rtw_security.c | 7 +++----
> 1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/staging/rtl8723bs/core/rtw_security.c b/drivers/staging/rtl8723bs/core/rtw_security.c
> index a99f439328f1..97a7485f8f58 100644
> --- a/drivers/staging/rtl8723bs/core/rtw_security.c
> +++ b/drivers/staging/rtl8723bs/core/rtw_security.c
> @@ -121,7 +121,7 @@ void rtw_wep_decrypt(struct adapter *padapter, u8 *precvframe)
> arc4_crypt(ctx, payload, payload, length);
>
> /* calculate icv and compare the icv */
> - *((u32 *)crc) = le32_to_cpu(~crc32_le(~0, payload, length - 4));
> + *crc = cpu_to_le32(~crc32_le(~0, payload, length - 4));

Huh? crc is u8[4]; that assignment will truncate that le32 to u8 and store it in
the first byte of your 4-element array. How the hell does sparse *not* complain
on that?

Either make crc __le32 (and turn assignment into crc = cpu_to_le32(...)), or
make that *(__le32 *)crc = ...

> @@ -618,10 +618,9 @@ u32 rtw_tkip_decrypt(struct adapter *padapter, u8 *precvframe)
> arc4_setkey(ctx, rc4key, 16);
> arc4_crypt(ctx, payload, payload, length);
>
> - *((u32 *)crc) = le32_to_cpu(~crc32_le(~0, payload, length - 4));
> + *crc = cpu_to_le32(~crc32_le(~0, payload, length - 4));

Ditto. Declare crc as __le32 and use
crc = cpu_to_le32(~crc32_le(~0, payload, length - 4));
here.

\
 
 \ /
  Last update: 2021-06-18 21:30    [W:0.165 / U:0.240 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site