diff options
| author | Stephen Worley <sworley@cumulusnetworks.com> | 2018-07-26 16:12:05 -0400 |
|---|---|---|
| committer | Stephen Worley <sworley@cumulusnetworks.com> | 2018-07-26 16:46:57 -0400 |
| commit | e6a0e0d1413a2cfb17be8374d82a1db555fd5ec2 (patch) | |
| tree | db51b97daf5b53f3cc67f058dca21321c39cd23e /zebra/kernel_netlink.c | |
| parent | 4b22e6bc053fe6349960b279c5bfa47bbba04b56 (diff) | |
zebra: Check for netlink message next fault
NLMSG_NEXT decrements the buffer length (status) by
the header msg length (nlmsg_len) everytime its called.
If nlmsg_len isn't accurate and set to be larger than
what it should represent, it will cause status to
decrement passed 0. This makes NLMSG_NEXT return a
pointer that references an inaccessible address.
When that is passed to NLMSG_OK, it segfaults.
Add a check to verify that there is still something to read
before we try to.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
Diffstat (limited to 'zebra/kernel_netlink.c')
| -rw-r--r-- | zebra/kernel_netlink.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/zebra/kernel_netlink.c b/zebra/kernel_netlink.c index 8703b01319..cd881dcc24 100644 --- a/zebra/kernel_netlink.c +++ b/zebra/kernel_netlink.c @@ -638,7 +638,7 @@ int netlink_parse_info(int (*filter)(struct nlmsghdr *, ns_id_t, int), read_in++; for (h = (struct nlmsghdr *)buf; - NLMSG_OK(h, (unsigned int)status); + (status >= 0 && NLMSG_OK(h, (unsigned int)status)); h = NLMSG_NEXT(h, status)) { /* Finish of reading. */ if (h->nlmsg_type == NLMSG_DONE) |