5.4-stable review patch. If anyone has any objections, please let me know.
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From: Dan Carpenter dan.carpenter@linaro.org
[ Upstream commit 80b78c39eb86e6b55f56363b709eb817527da5aa ]
The get->num_services variable is an unsigned int which is controlled by the user. The struct_size() function ensures that the size calculation does not overflow an unsigned long, however, we are saving the result to an int so the calculation can overflow.
Both "len" and "get->num_services" come from the user. This check is just a sanity check to help the user and ensure they are using the API correctly. An integer overflow here is not a big deal. This has no security impact.
Save the result from struct_size() type size_t to fix this integer overflow bug.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Dan Carpenter dan.carpenter@linaro.org Acked-by: Julian Anastasov ja@ssi.bg Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/netfilter/ipvs/ip_vs_ctl.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c index 2bc82dabfe3b8..dcce6aaac970e 100644 --- a/net/netfilter/ipvs/ip_vs_ctl.c +++ b/net/netfilter/ipvs/ip_vs_ctl.c @@ -2809,12 +2809,12 @@ do_ip_vs_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) case IP_VS_SO_GET_SERVICES: { struct ip_vs_get_services *get; - int size; + size_t size;
get = (struct ip_vs_get_services *)arg; size = struct_size(get, entrytable, get->num_services); if (*len != size) { - pr_err("length: %u != %u\n", *len, size); + pr_err("length: %u != %zu\n", *len, size); ret = -EINVAL; goto out; } @@ -2850,12 +2850,12 @@ do_ip_vs_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) case IP_VS_SO_GET_DESTS: { struct ip_vs_get_dests *get; - int size; + size_t size;
get = (struct ip_vs_get_dests *)arg; size = struct_size(get, entrytable, get->num_dests); if (*len != size) { - pr_err("length: %u != %u\n", *len, size); + pr_err("length: %u != %zu\n", *len, size); ret = -EINVAL; goto out; }