[PATCH 3.14 15/68] netlink: rate-limit leftover bytes warning and print process name

Greg Kroah-Hartman
2014-06-24T15:53:45Z

From: Michal Schmidt <mschmidt@redhat.com>

[ Upstream commit bfc5184b69cf9eeb286137640351c650c27f118a ]

Any process is able to send netlink messages with leftover bytes.
Make the warning rate-limited to prevent too much log spam.

The warning is supposed to help find userspace bugs, so print the
triggering command name to implicate the buggy program.

[v2: Use pr_warn_ratelimited instead of printk_ratelimited.]

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
lib/nlattr.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/lib/nlattr.c
+++ b/lib/nlattr.c
@@ -201,8 +201,8 @@ int nla_parse(struct nlattr **tb, int ma
}

if (unlikely(rem > 0))
- printk(KERN_WARNING "netlink: %d bytes leftover after parsing "
- "attributes.\n", rem);
+ pr_warn_ratelimited("netlink: %d bytes leftover after parsing attributes in process `%s'.\n",
+ rem, current->comm);

err = 0;