Thread (3 messages) 3 messages, 3 authors, 2019-06-04

Re: [PATCH] rose: af_rose: avoid overflows in rose_setsockopt()

From: walter harms <hidden>
Date: 2019-06-04 13:14:02
Also in: linux-hams, lkml


Am 04.06.2019 14:11, schrieb Young Xiao:
quoted hunk ↗ jump to hunk
Check setsockopt arguments to avoid overflows and return -EINVAL for
too large arguments.

See commit 32288eb4d940 ("netrom: avoid overflows in nr_setsockopt()")
for details.

Signed-off-by: Young Xiao <redacted>
---
 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 e274bc6..af831ee9 100644
--- a/net/rose/af_rose.c
+++ b/net/rose/af_rose.c
@@ -372,15 +372,15 @@ 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 long opt;
 
 	if (level != SOL_ROSE)
 		return -ENOPROTOOPT;
 
-	if (optlen < sizeof(int))
+	if (optlen < sizeof(unsigned int))
 		return -EINVAL;
I do not thing that this will change much,
but maybe you would like to check against the sizeof (opt) here ?

quoted hunk ↗ jump to hunk
 
-	if (get_user(opt, (int __user *)optval))
+	if (get_user(opt, (unsigned int __user *)optval))
 		return -EFAULT;
 
 	switch (optname) {
@@ -389,31 +389,31 @@ static int rose_setsockopt(struct socket *sock, int level, int optname,
 		return 0;
 
 	case ROSE_T1:
-		if (opt < 1)
+		if (opt < 1 || opt > ULONG_MAX / HZ)
 			return -EINVAL;
 		rose->t1 = opt * HZ;
 		return 0;
 
 	case ROSE_T2:
-		if (opt < 1)
+		if (opt < 1 || opt > ULONG_MAX / HZ)
 			return -EINVAL;
 		rose->t2 = opt * HZ;
 		return 0;
 
 	case ROSE_T3:
-		if (opt < 1)
+		if (opt < 1 || opt > ULONG_MAX / HZ)
 			return -EINVAL;
 		rose->t3 = opt * HZ;
 		return 0;
 
 	case ROSE_HOLDBACK:
-		if (opt < 1)
+		if (opt < 1 || opt > ULONG_MAX / HZ)
 			return -EINVAL;
 		rose->hb = opt * HZ;
 		return 0;
 you can simplify this jungle by checking and calculation first
 and then set the correct rose->XX
 
 	case ROSE_IDLE:
-		if (opt < 0)
+		if (opt < 0 || opt > ULONG_MAX / HZ)
 			return -EINVAL;
You made opt unsigned or ?
 		rose->idle = opt * 60 * HZ;
 		return 0;
my 2 cents,

re,
 wh
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help