netfilter: nft_osf: add missing check for DREG attribute
authorFlorian Westphal <fw@strlen.de>
Sat, 18 Jan 2020 10:27:25 +0000 (11:27 +0100)
committerPablo Neira Ayuso <pablo@netfilter.org>
Sat, 18 Jan 2020 20:18:41 +0000 (21:18 +0100)
commit7eaecf7963c1c8f62d62c6a8e7c439b0e7f2d365
tree6a92db0a598fc59b45ce86400542a92a90033e97
parente02d9c4c68dc0ca08ded9487720bba775c09669b
netfilter: nft_osf: add missing check for DREG attribute

syzbot reports just another NULL deref crash because of missing test
for presence of the attribute.

Reported-by: syzbot+cf23983d697c26c34f60@syzkaller.appspotmail.com
Fixes:  b96af92d6eaf9fadd ("netfilter: nf_tables: implement Passive OS fingerprint module in nft_osf")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
net/netfilter/nft_osf.c