From f4e4534850a9d18c250a93f8d7fbb51310828110 Mon Sep 17 00:00:00 2001 From: Pedro Tammela Date: Mon, 29 May 2023 12:33:35 -0300 Subject: [PATCH] net/netlink: fix NETLINK_LIST_MEMBERSHIPS length report The current code for the length calculation wrongly truncates the reported length of the groups array, causing an under report of the subscribed groups. To fix this, use 'BITS_TO_BYTES()' which rounds up the division by 8. Fixes: b42be38b2778 ("netlink: add API to retrieve all group memberships") Signed-off-by: Pedro Tammela Reviewed-by: Simon Horman Link: https://lore.kernel.org/r/20230529153335.389815-1-pctammela@mojatatu.com Signed-off-by: Jakub Kicinski --- net/netlink/af_netlink.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index c878041..3a1e0fd 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -1779,7 +1779,7 @@ static int netlink_getsockopt(struct socket *sock, int level, int optname, break; } } - if (put_user(ALIGN(nlk->ngroups / 8, sizeof(u32)), optlen)) + if (put_user(ALIGN(BITS_TO_BYTES(nlk->ngroups), sizeof(u32)), optlen)) err = -EFAULT; netlink_unlock_table(); return err; -- 2.7.4