netdev - Re: [PATCH net] net/rose: prevent integer overflows in rose

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <6f79c23a-7acb-5faf-5e8d-104ca37dbb08@nfschina.com>
Date: Thu, 16 Jan 2025 10:04:47 +0800
From: Su Hui <suhui@...china.com>
To: David Laight <david.laight.linux@...il.com>,
 Nikita Zhandarovich <n.zhandarovich@...tech.ru>
Cc: "David S. Miller" <davem@...emloft.net>,
 Eric Dumazet <edumazet@...gle.com>, Jakub Kicinski <kuba@...nel.org>,
 Paolo Abeni <pabeni@...hat.com>, Simon Horman <horms@...nel.org>,
 linux-hams@...r.kernel.org, netdev@...r.kernel.org,
 linux-kernel@...r.kernel.org, lvc-project@...uxtesting.org,
 stable@...r.kernel.org, kernel-janitors@...r.kernel.org
Subject: Re: [PATCH net] net/rose: prevent integer overflows in
 rose_setsockopt()

On 2025/1/16 07:29, David Laight wrote:
> On Wed, 15 Jan 2025 08:42:20 -0800
> Nikita Zhandarovich <n.zhandarovich@...tech.ru> wrote:
>
>> In case of possible unpredictably large arguments passed to
>> rose_setsockopt() and multiplied by extra values on top of that,
>> integer overflows may occur.
>>
>> Do the safest minimum and fix these issues by checking the
>> contents of 'opt' and returning -EINVAL if they are too large. Also,
>> switch to unsigned int and remove useless check for negative 'opt'
>> in ROSE_IDLE case.
>>
>> Found by Linux Verification Center (linuxtesting.org) with static
>> analysis tool SVACE.
>>
>> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
>> Cc: stable@...r.kernel.org
>> Signed-off-by: Nikita Zhandarovich <n.zhandarovich@...tech.ru>
>> ---
>>   net/rose/af_rose.c | 16 ++++++++--------
>>   1 file changed, 8 insertions(+), 8 deletions(-)
>>
>> diff --git a/net/rose/af_rose.c b/net/rose/af_rose.c
>> index 59050caab65c..72c65d938a15 100644
>> --- a/net/rose/af_rose.c
>> +++ b/net/rose/af_rose.c
>> @@ -397,15 +397,15 @@ static int rose_setsockopt(struct socket *sock, int level, int optname,
>>   {
>>   	struct sock *sk = sock->sk;
>>   	struct rose_sock *rose = rose_sk(sk);
>> -	int opt;
>> +	unsigned int opt;
>>   
>>   	if (level != SOL_ROSE)
>>   		return -ENOPROTOOPT;
>>   
>> -	if (optlen < sizeof(int))
>> +	if (optlen < sizeof(unsigned int))
>>   		return -EINVAL;
>>   
>> -	if (copy_from_sockptr(&opt, optval, sizeof(int)))
>> +	if (copy_from_sockptr(&opt, optval, sizeof(unsigned int)))
> Shouldn't all those be 'sizeof (opt)' ?
>
> 	David
>
>>   		return -EFAULT;
>>   
>>   	switch (optname) {
>> @@ -414,31 +414,31 @@ static int rose_setsockopt(struct socket *sock, int level, int optname,
>>   		return 0;
>>   
>>   	case ROSE_T1:
>> -		if (opt < 1)
>> +		if (opt < 1 || opt > UINT_MAX / HZ)

'rose->t1' is unsigned long, how about 'opt > ULONG_MAX / HZ' ?

BTW, I think only in 32bit or 16bit machine when 'sizeof(int) == 
sizeof(unsigned long)',
this integer overflows may occur..

Su Hui

>>   			return -EINVAL;
>>   		rose->t1 = opt * HZ;
>>   		return 0;
>>   
>>   	case ROSE_T2:
>> -		if (opt < 1)
>> +		if (opt < 1 || opt > UINT_MAX / HZ)
>>   			return -EINVAL;
>>   		rose->t2 = opt * HZ;
>>   		return 0;
>>   
>>   	case ROSE_T3:
>> -		if (opt < 1)
>> +		if (opt < 1 || opt > UINT_MAX / HZ)
>>   			return -EINVAL;
>>   		rose->t3 = opt * HZ;
>>   		return 0;
>>   
>>   	case ROSE_HOLDBACK:
>> -		if (opt < 1)
>> +		if (opt < 1 || opt > UINT_MAX / HZ)
>>   			return -EINVAL;
>>   		rose->hb = opt * HZ;
>>   		return 0;
>>   
>>   	case ROSE_IDLE:
>> -		if (opt < 0)
>> +		if (opt > UINT_MAX / (60 * HZ))
>>   			return -EINVAL;
>>   		rose->idle = opt * 60 * HZ;
>>   		return 0;
>>