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| author | Florian Westphal <fw@strlen.de> | 2022-09-20 19:31:30 +0300 |
|---|---|---|
| committer | Florian Westphal <fw@strlen.de> | 2022-09-21 00:50:03 +0300 |
| commit | d25088932227680988a6b794221e031a7232f137 (patch) | |
| tree | bca64dc14c6152bc59d66cf092b67b32c38061e2 /net/netfilter | |
| parent | 62ce44c4fff947eebdf10bb582267e686e6835c9 (diff) | |
| download | linux-d25088932227680988a6b794221e031a7232f137.tar.xz | |
netfilter: nf_ct_ftp: fix deadlock when nat rewrite is needed
We can't use ct->lock, this is already used by the seqadj internals.
When using ftp helper + nat, seqadj will attempt to acquire ct->lock
again.
Revert back to a global lock for now.
Fixes: c783a29c7e59 ("netfilter: nf_ct_ftp: prefer skb_linearize")
Reported-by: Bruno de Paula Larini <bruno.larini@riosoft.com.br>
Signed-off-by: Florian Westphal <fw@strlen.de>
Diffstat (limited to 'net/netfilter')
| -rw-r--r-- | net/netfilter/nf_conntrack_ftp.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/net/netfilter/nf_conntrack_ftp.c b/net/netfilter/nf_conntrack_ftp.c index 0d9332e9cf71..617f744a2e3a 100644 --- a/net/netfilter/nf_conntrack_ftp.c +++ b/net/netfilter/nf_conntrack_ftp.c @@ -33,6 +33,7 @@ MODULE_AUTHOR("Rusty Russell <rusty@rustcorp.com.au>"); MODULE_DESCRIPTION("ftp connection tracking helper"); MODULE_ALIAS("ip_conntrack_ftp"); MODULE_ALIAS_NFCT_HELPER(HELPER_NAME); +static DEFINE_SPINLOCK(nf_ftp_lock); #define MAX_PORTS 8 static u_int16_t ports[MAX_PORTS]; @@ -409,7 +410,8 @@ static int help(struct sk_buff *skb, } datalen = skb->len - dataoff; - spin_lock_bh(&ct->lock); + /* seqadj (nat) uses ct->lock internally, nf_nat_ftp would cause deadlock */ + spin_lock_bh(&nf_ftp_lock); fb_ptr = skb->data + dataoff; ends_in_nl = (fb_ptr[datalen - 1] == '\n'); @@ -538,7 +540,7 @@ out_update_nl: if (ends_in_nl) update_nl_seq(ct, seq, ct_ftp_info, dir, skb); out: - spin_unlock_bh(&ct->lock); + spin_unlock_bh(&nf_ftp_lock); return ret; } |