Merge branch 'mptcp-fixes'
Mat Martineau says:
====================
mptcp: Fixes for buffer reclaim and option writing
Here are three fixes dealing with a syzkaller crash MPTCP triggers in
the memory manager in 5.16-rc8, and some option writing problems.
Patches 1 and 2 fix some corner cases in MPTCP option writing.
Patch 3 addresses a crash that syzkaller found a way to trigger in the mm
subsystem by passing an invalid value to __sk_mem_reduce_allocated().
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index fe98e4f..6661b1d 100644
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -821,10 +821,13 @@
if (mptcp_established_options_mp(sk, skb, snd_data_fin, &opt_size, remaining, opts))
ret = true;
else if (mptcp_established_options_dss(sk, skb, snd_data_fin, &opt_size, remaining, opts)) {
+ unsigned int mp_fail_size;
+
ret = true;
- if (mptcp_established_options_mp_fail(sk, &opt_size, remaining, opts)) {
- *size += opt_size;
- remaining -= opt_size;
+ if (mptcp_established_options_mp_fail(sk, &mp_fail_size,
+ remaining - opt_size, opts)) {
+ *size += opt_size + mp_fail_size;
+ remaining -= opt_size - mp_fail_size;
return true;
}
}
@@ -1316,6 +1319,7 @@
put_unaligned_be32(mpext->data_len << 16 |
TCPOPT_NOP << 8 | TCPOPT_NOP, ptr);
}
+ ptr += 1;
}
} else if (OPTIONS_MPTCP_MPC & opts->suboptions) {
u8 len, flag = MPTCP_CAP_HMAC_SHA256;
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 54613f5..0cd55e4 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -972,7 +972,9 @@
lockdep_assert_held_once(&sk->sk_lock.slock);
- __mptcp_rmem_reclaim(sk, reclaimable - 1);
+ if (reclaimable > SK_MEM_QUANTUM)
+ __mptcp_rmem_reclaim(sk, reclaimable - 1);
+
sk_mem_reclaim_partial(sk);
}
