This is a note to let you know that I've just added the patch titled
net/netlink: fix NETLINK_LIST_MEMBERSHIPS length report
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-netlink-fix-netlink_list_memberships-length-repo.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit a72a3831af62e45acccd229e9b4cf99bfebfdc9f
Author: Pedro Tammela <pctammela@xxxxxxxxxxxx>
Date: Mon May 29 12:33:35 2023 -0300
net/netlink: fix NETLINK_LIST_MEMBERSHIPS length report
[ Upstream commit f4e4534850a9d18c250a93f8d7fbb51310828110 ]
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 <pctammela@xxxxxxxxxxxx>
Reviewed-by: Simon Horman <simon.horman@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230529153335.389815-1-pctammela@xxxxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 31a3a562854fc..bf7e300e8c25d 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -1780,7 +1780,7 @@ 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;
