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| author | Dmitry Safonov <dima@arista.com> | 2018-07-30 18:32:36 +0100 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2018-11-20 18:05:53 +0000 |
| commit | 853d59debb492d6b5bd9751bdb2e9e0119c137a6 (patch) | |
| tree | 6b3607e776c947642dbb9212d2815986156fcf9c /net/netlink | |
| parent | a7bfa34a431f949e76c460ace85c5357a8c75206 (diff) | |
| download | linux-stable-853d59debb492d6b5bd9751bdb2e9e0119c137a6.tar.gz linux-stable-853d59debb492d6b5bd9751bdb2e9e0119c137a6.tar.bz2 linux-stable-853d59debb492d6b5bd9751bdb2e9e0119c137a6.zip | |
netlink: Don't shift with UB on nlk->ngroups
commit 61f4b23769f0cc72ae62c9a81cf08f0397d40da8 upstream.
On i386 nlk->ngroups might be 32 or 0. Which leads to UB, resulting in
hang during boot.
Check for 0 ngroups and use (unsigned long long) as a type to shift.
Fixes: 7acf9d4237c4 ("netlink: Do not subscribe to non-existent groups").
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'net/netlink')
| -rw-r--r-- | net/netlink/af_netlink.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 10cdd150b000..ff382bb578f1 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -927,7 +927,11 @@ static int netlink_bind(struct socket *sock, struct sockaddr *addr, if (err) return err; } - groups &= (1UL << nlk->ngroups) - 1; + + if (nlk->ngroups == 0) + groups = 0; + else + groups &= (1ULL << nlk->ngroups) - 1; if (nlk->portid) if (nladdr->nl_pid != nlk->portid) |