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@vger.kernel.org Signed-off-by: Nikita Zhandarovich n.zhandarovich@fintech.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))) 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) 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;