Re: [dpdk-dev] [PATCH v2] app/test: fix array subscript is above array bounds for gcc 4.5

["De Lara Guarch, Pablo" <pablo.de.lara.guarch@intel.com>]

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Tomasz Kulasek
> Sent: Thursday, April 07, 2016 3:02 PM
> To: dev@dpdk.org
> Subject: [dpdk-dev] [PATCH v2] app/test: fix array subscript is above array
> bounds for gcc 4.5
> 
> cc1: warnings being treated as errors
> DPDK/app/test/test_cryptodev.c: In function
> 'test_snow3g_encrypted_authenti
> cation.clone.3':
> DPDK/x86_64-ivshmem-linuxapp-gcc/include/rte_memcpy.h:796:14: error:
> array
> subscript is above array bounds
> compilation terminated due to -Wfatal-errors.
> 
> 
> ROOT OF PROBLEM:
> ----------------
> 
> In lines like:
> 
>     rte_memcpy(sym_op->cipher.iv.data, iv, iv_len);
> 
> when "iv" is 64 bytes long array, and "iv_len" is "unsigned int",
> compiler tries to evaluate also a code for array size larger than 255 bytes
> long and reports error "array subscript is above array bounds" in line:
> 
> rte_memcpy.h:796
> 
>     rte_mov128((uint8_t *)dst + 128, (const uint8_t *)src + 128);
> 
> caused by evaluation to:
> 
>     rte_mov128((uint8_t *)sym_op->cipher.iv.data + 128, (const uint8_t *)iv
> 			+ 128);
> 
> where "iv" is 64 bytes long buffer and "iv + 128" point out of it, gcc 4.5.
> 
> 
> SOLUTION:
> ---------
> 
> Using uint8_t as a size of copied block prevents to evaluate in rte_memcpy
> code for length bigger than 255, causing the problem.
> 
> v2 changes:
>  - added fixline
> 
> Fixes: 8bdf665fe6c0 ("app/test: add SNOW 3G")
> 
> Signed-off-by: Tomasz Kulasek <tomaszx.kulasek@intel.com>

Acked-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>