From 04bcef2a83f40c6db24222b27a52892cba39dffb Mon Sep 17 00:00:00 2001 From: Arjan van de Ven Date: Mon, 4 Jan 2010 16:37:12 +0100 Subject: [PATCH] ipvs: Add boundary check on ioctl arguments The ipvs code has a nifty system for doing the size of ioctl command copies; it defines an array with values into which it indexes the cmd to find the right length. Unfortunately, the ipvs code forgot to check if the cmd was in the range that the array provides, allowing for an index outside of the array, which then gives a "garbage" result into the length, which then gets used for copying into a stack buffer. Fix this by adding sanity checks on these as well as the copy size. [ horms@verge.net.au: adjusted limit to IP_VS_SO_GET_MAX ] Signed-off-by: Arjan van de Ven Acked-by: Julian Anastasov Signed-off-by: Simon Horman Signed-off-by: Patrick McHardy --- net/netfilter/ipvs/ip_vs_ctl.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c index 6bde12da2fe0..c37ac2d7bec4 100644 --- a/net/netfilter/ipvs/ip_vs_ctl.c +++ b/net/netfilter/ipvs/ip_vs_ctl.c @@ -2077,6 +2077,10 @@ do_ip_vs_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) if (!capable(CAP_NET_ADMIN)) return -EPERM; + if (cmd < IP_VS_BASE_CTL || cmd > IP_VS_SO_SET_MAX) + return -EINVAL; + if (len < 0 || len > MAX_ARG_LEN) + return -EINVAL; if (len != set_arglen[SET_CMDID(cmd)]) { pr_err("set_ctl: len %u != %u\n", len, set_arglen[SET_CMDID(cmd)]); @@ -2352,17 +2356,25 @@ do_ip_vs_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) { unsigned char arg[128]; int ret = 0; + unsigned int copylen; if (!capable(CAP_NET_ADMIN)) return -EPERM; + if (cmd < IP_VS_BASE_CTL || cmd > IP_VS_SO_GET_MAX) + return -EINVAL; + if (*len < get_arglen[GET_CMDID(cmd)]) { pr_err("get_ctl: len %u < %u\n", *len, get_arglen[GET_CMDID(cmd)]); return -EINVAL; } - if (copy_from_user(arg, user, get_arglen[GET_CMDID(cmd)]) != 0) + copylen = get_arglen[GET_CMDID(cmd)]; + if (copylen > 128) + return -EINVAL; + + if (copy_from_user(arg, user, copylen) != 0) return -EFAULT; if (mutex_lock_interruptible(&__ip_vs_mutex)) -- 2.20.1