[dpdk-dev] [PATCH] mem: fix overflowed return value
>-Original Message-
>From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Stephen Hemminger
>Sent: Friday, April 22, 2016 6:25 PM
>To: Kobylinski, MichalX
>Cc: thomas.monjalon at 6wind.com; dev at dpdk.org
>Subject: Re: [dpdk-dev] [PATCH] mem: fix overflowed return value
>
>On Fri, 22 Apr 2016 12:44:18 +0200
>Michal Kobylinski wrote:
>
>> Fix issue reported by Coverity.
>>
>> Coverity ID 13255: Overflowed return value: The return value will be too
>> small or even negative, likely resulting in unexpected behavior in a
>> caller that uses the return value. In rte_mem_virt2phy: An integer
>> overflow occurs, with the overflowed value used as the return value of
>> the function
>>
>> Fixes: 3097de6e6bfb ("mem: get physical address of any pointer")
>>
>> Signed-off-by: Michal Kobylinski
>> ---
>> lib/librte_eal/linuxapp/eal/eal_memory.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/lib/librte_eal/linuxapp/eal/eal_memory.c
>b/lib/librte_eal/linuxapp/eal/eal_memory.c
>> index 5b9132c..6ceca5b 100644
>> --- a/lib/librte_eal/linuxapp/eal/eal_memory.c
>> +++ b/lib/librte_eal/linuxapp/eal/eal_memory.c
>> @@ -195,7 +195,7 @@ rte_mem_virt2phy(const void *virtaddr)
>> * the pfn (page frame number) are bits 0-54 (see
>> * pagemap.txt in linux Documentation)
>> */
>> -physaddr = ((page & 0x7fULL) * page_size)
>> +physaddr = (uint64_t)((page & 0x7fULL) * page_size)
>> + ((unsigned long)virtaddr % page_size);
>> close(fd);
>> return physaddr;
>
>I am not trusting any of these Coverity patches you are sending.
>It seems you think wraparound can be just fixed by casting, it can't
>From my point of view it's False Possitive there is no chance that page_size
>will be bigger than long.
Coverity Assume that page_size may be 18446744071562067968 but it can't.
Only for glibc<2.1 we probably should change page_size = getpagesize(); to
page_size = sysconf(_SC_PAGESIZE);
May I change this Coverity to False Positive or I missed something ? What's
your opinion ?
[dpdk-dev] [PATCH] mem: fix overflowed return value
Fix issue reported by Coverity.
Coverity ID 13255: Overflowed return value: The return value will be too
small or even negative, likely resulting in unexpected behavior in a
caller that uses the return value. In rte_mem_virt2phy: An integer
overflow occurs, with the overflowed value used as the return value of
the function
Fixes: 3097de6e6bfb ("mem: get physical address of any pointer")
Signed-off-by: Michal Kobylinski
---
lib/librte_eal/linuxapp/eal/eal_memory.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/librte_eal/linuxapp/eal/eal_memory.c
b/lib/librte_eal/linuxapp/eal/eal_memory.c
index 5b9132c..6ceca5b 100644
--- a/lib/librte_eal/linuxapp/eal/eal_memory.c
+++ b/lib/librte_eal/linuxapp/eal/eal_memory.c
@@ -195,7 +195,7 @@ rte_mem_virt2phy(const void *virtaddr)
* the pfn (page frame number) are bits 0-54 (see
* pagemap.txt in linux Documentation)
*/
- physaddr = ((page & 0x7fULL) * page_size)
+ physaddr = (uint64_t)((page & 0x7fULL) * page_size)
+ ((unsigned long)virtaddr % page_size);
close(fd);
return physaddr;
--
1.9.1
[dpdk-dev] [PATCH] mem: fix overflowed return value
On Fri, 22 Apr 2016 12:44:18 +0200
Michal Kobylinski wrote:
> Fix issue reported by Coverity.
>
> Coverity ID 13255: Overflowed return value: The return value will be too
> small or even negative, likely resulting in unexpected behavior in a
> caller that uses the return value. In rte_mem_virt2phy: An integer
> overflow occurs, with the overflowed value used as the return value of
> the function
>
> Fixes: 3097de6e6bfb ("mem: get physical address of any pointer")
>
> Signed-off-by: Michal Kobylinski
> ---
> lib/librte_eal/linuxapp/eal/eal_memory.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/lib/librte_eal/linuxapp/eal/eal_memory.c
> b/lib/librte_eal/linuxapp/eal/eal_memory.c
> index 5b9132c..6ceca5b 100644
> --- a/lib/librte_eal/linuxapp/eal/eal_memory.c
> +++ b/lib/librte_eal/linuxapp/eal/eal_memory.c
> @@ -195,7 +195,7 @@ rte_mem_virt2phy(const void *virtaddr)
>* the pfn (page frame number) are bits 0-54 (see
>* pagemap.txt in linux Documentation)
>*/
> - physaddr = ((page & 0x7fULL) * page_size)
> + physaddr = (uint64_t)((page & 0x7fULL) * page_size)
> + ((unsigned long)virtaddr % page_size);
> close(fd);
> return physaddr;
I am not trusting any of these Coverity patches you are sending.
It seems you think wraparound can be just fixed by casting, it can't
