diff options
author | Dan Carpenter <dan.carpenter@oracle.com> | 2015-08-01 15:33:26 +0300 |
---|---|---|
committer | Luis Henriques <luis.henriques@canonical.com> | 2015-08-27 16:15:44 +0300 |
commit | a7fc16eff90922ba52faace0da2b62937a66abe6 (patch) | |
tree | e25879a533635f65bc55d509881094444486cea8 | |
parent | d92e2723cb71144c8d38a9f75c214011a72ba1aa (diff) | |
download | linux-a7fc16eff90922ba52faace0da2b62937a66abe6.tar.xz |
rds: fix an integer overflow test in rds_info_getsockopt()
commit 468b732b6f76b138c0926eadf38ac88467dcd271 upstream.
"len" is a signed integer. We check that len is not negative, so it
goes from zero to INT_MAX. PAGE_SIZE is unsigned long so the comparison
is type promoted to unsigned long. ULONG_MAX - 4095 is a higher than
INT_MAX so the condition can never be true.
I don't know if this is harmful but it seems safe to limit "len" to
INT_MAX - 4095.
Fixes: a8c879a7ee98 ('RDS: Info and stats')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
-rw-r--r-- | net/rds/info.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/rds/info.c b/net/rds/info.c index 9a6b4f66187c..140a44a5f7b7 100644 --- a/net/rds/info.c +++ b/net/rds/info.c @@ -176,7 +176,7 @@ int rds_info_getsockopt(struct socket *sock, int optname, char __user *optval, /* check for all kinds of wrapping and the like */ start = (unsigned long)optval; - if (len < 0 || len + PAGE_SIZE - 1 < len || start + len < start) { + if (len < 0 || len > INT_MAX - PAGE_SIZE + 1 || start + len < start) { ret = -EINVAL; goto out; } |