[PATCH ipsec-next 0/6] xfrm: remove xfrm replay indirections

[PATCH ipsec-next 0/6] xfrm: remove xfrm replay indirections

[Florian Westphal]

The xfrm replay logic is implemented via indirect calls.

xfrm_state struct holds a pointer to a
'struct xfrm_replay', which is one of several replay protection
backends.

XFRM then invokes the backend via state->repl->callback().
Due to retpoline all indirect calls have become a lot more
expensive.  Fortunately, there are no 'replay modules', all are available
for direct calls.

This series removes the 'struct xfrm_replay' and adds replay
functions that can be called instead of the redirection.

Example:
  -  err = x->repl->overflow(x, skb);
  +  err = xfrm_replay_overflow(x, skb);

Instead of a pointer to a struct with function pointers, xfrm_state
now holds an enum that tells the replay core what kind of replay
test is to be done.

Florian Westphal (6):
      xfrm: replay: avoid xfrm replay notify indirection
      xfrm: replay: get rid of duplicated notification code
      xfrm: replay: remove advance indirection
      xfrm: replay: remove recheck indirection
      xfrm: replay: avoid replay indirection
      xfrm: replay: remove last replay indirection

 include/net/xfrm.h     |  29 ++++----
 net/xfrm/xfrm_input.c  |   6 +-
 net/xfrm/xfrm_output.c |   2 +-
 net/xfrm/xfrm_replay.c | 189 +++++++++++++++++++++++++++----------------------
 net/xfrm/xfrm_state.c  |   2 +-
 5 files changed, 124 insertions(+), 104 deletions(-)

[PATCH ipsec-next 1/6] xfrm: replay: avoid xfrm replay notify indirection

[Florian Westphal]

replay protection is implemented using a callback structure and then
called via

   x->repl->notify(), x->repl->recheck(), and so on.

all the differect functions are always built-in, so this could be direct
calls instead.

This first patch prepares for removal of the x->repl structure.
Add an enum with the three available replay modes to the xfrm_state
structure and then replace all x->repl->notify() calls by the new
xfrm_replay_notify() helper.

The helper checks the enum internally to adapt behaviour as needed.

Signed-off-by: Florian Westphal <fw@strlen.de>
---
 include/net/xfrm.h     | 11 ++++++++++-
 net/xfrm/xfrm_replay.c | 45 ++++++++++++++++++++++++++----------------
 net/xfrm/xfrm_state.c  |  2 +-
 3 files changed, 39 insertions(+), 19 deletions(-)

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index e20b2b27ec48..ed105257c5a8 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -144,6 +144,12 @@ enum {
 	XFRM_MODE_FLAG_TUNNEL = 1,
 };
 
+enum xfrm_replay_mode {
+	XFRM_REPLAY_MODE_LEGACY,
+	XFRM_REPLAY_MODE_BMP,
+	XFRM_REPLAY_MODE_ESN,
+};
+
 /* Full description of state of transformer. */
 struct xfrm_state {
 	possible_net_t		xs_net;
@@ -216,6 +222,8 @@ struct xfrm_state {
 	/* The functions for replay detection. */
 	const struct xfrm_replay *repl;
 
+	/* replay detection mode */
+	enum xfrm_replay_mode    repl_mode;
 	/* internal flag that only holds state for delayed aevent at the
 	 * moment
 	*/
@@ -303,7 +311,6 @@ struct xfrm_replay {
 	int	(*recheck)(struct xfrm_state *x,
 			   struct sk_buff *skb,
 			   __be32 net_seq);
-	void	(*notify)(struct xfrm_state *x, int event);
 	int	(*overflow)(struct xfrm_state *x, struct sk_buff *skb);
 };
 
@@ -1712,6 +1719,8 @@ static inline int xfrm_policy_id2dir(u32 index)
 }
 
 #ifdef CONFIG_XFRM
+void xfrm_replay_notify(struct xfrm_state *x, int event);
+
 static inline int xfrm_aevent_is_on(struct net *net)
 {
 	struct sock *nlsk;
diff --git a/net/xfrm/xfrm_replay.c b/net/xfrm/xfrm_replay.c
index 98943f8d01aa..e42a7afb8ee5 100644
--- a/net/xfrm/xfrm_replay.c
+++ b/net/xfrm/xfrm_replay.c
@@ -34,8 +34,11 @@ u32 xfrm_replay_seqhi(struct xfrm_state *x, __be32 net_seq)
 	return seq_hi;
 }
 EXPORT_SYMBOL(xfrm_replay_seqhi);
-;
-static void xfrm_replay_notify(struct xfrm_state *x, int event)
+
+static void xfrm_replay_notify_bmp(struct xfrm_state *x, int event);
+static void xfrm_replay_notify_esn(struct xfrm_state *x, int event);
+
+void xfrm_replay_notify(struct xfrm_state *x, int event)
 {
 	struct km_event c;
 	/* we send notify messages in case
@@ -48,6 +51,17 @@ static void xfrm_replay_notify(struct xfrm_state *x, int event)
 	 *  The state structure must be locked!
 	 */
 
+	switch (x->repl_mode) {
+	case XFRM_REPLAY_MODE_LEGACY:
+		break;
+	case XFRM_REPLAY_MODE_BMP:
+		xfrm_replay_notify_bmp(x, event);
+		return;
+	case XFRM_REPLAY_MODE_ESN:
+		xfrm_replay_notify_esn(x, event);
+		return;
+	}
+
 	switch (event) {
 	case XFRM_REPLAY_UPDATE:
 		if (!x->replay_maxdiff ||
@@ -97,7 +111,7 @@ static int xfrm_replay_overflow(struct xfrm_state *x, struct sk_buff *skb)
 			return err;
 		}
 		if (xfrm_aevent_is_on(net))
-			x->repl->notify(x, XFRM_REPLAY_UPDATE);
+			xfrm_replay_notify(x, XFRM_REPLAY_UPDATE);
 	}
 
 	return err;
@@ -156,7 +170,7 @@ static void xfrm_replay_advance(struct xfrm_state *x, __be32 net_seq)
 	}
 
 	if (xfrm_aevent_is_on(xs_net(x)))
-		x->repl->notify(x, XFRM_REPLAY_UPDATE);
+		xfrm_replay_notify(x, XFRM_REPLAY_UPDATE);
 }
 
 static int xfrm_replay_overflow_bmp(struct xfrm_state *x, struct sk_buff *skb)
@@ -176,7 +190,7 @@ static int xfrm_replay_overflow_bmp(struct xfrm_state *x, struct sk_buff *skb)
 			return err;
 		}
 		if (xfrm_aevent_is_on(net))
-			x->repl->notify(x, XFRM_REPLAY_UPDATE);
+			xfrm_replay_notify(x, XFRM_REPLAY_UPDATE);
 	}
 
 	return err;
@@ -271,7 +285,7 @@ static void xfrm_replay_advance_bmp(struct xfrm_state *x, __be32 net_seq)
 	replay_esn->bmp[nr] |= (1U << bitnr);
 
 	if (xfrm_aevent_is_on(xs_net(x)))
-		x->repl->notify(x, XFRM_REPLAY_UPDATE);
+		xfrm_replay_notify(x, XFRM_REPLAY_UPDATE);
 }
 
 static void xfrm_replay_notify_bmp(struct xfrm_state *x, int event)
@@ -414,7 +428,7 @@ static int xfrm_replay_overflow_esn(struct xfrm_state *x, struct sk_buff *skb)
 			}
 		}
 		if (xfrm_aevent_is_on(net))
-			x->repl->notify(x, XFRM_REPLAY_UPDATE);
+			xfrm_replay_notify(x, XFRM_REPLAY_UPDATE);
 	}
 
 	return err;
@@ -546,7 +560,7 @@ static void xfrm_replay_advance_esn(struct xfrm_state *x, __be32 net_seq)
 	replay_esn->bmp[nr] |= (1U << bitnr);
 
 	if (xfrm_aevent_is_on(xs_net(x)))
-		x->repl->notify(x, XFRM_REPLAY_UPDATE);
+		xfrm_replay_notify(x, XFRM_REPLAY_UPDATE);
 }
 
 #ifdef CONFIG_XFRM_OFFLOAD
@@ -582,7 +596,7 @@ static int xfrm_replay_overflow_offload(struct xfrm_state *x, struct sk_buff *sk
 		x->replay.oseq = oseq;
 
 		if (xfrm_aevent_is_on(net))
-			x->repl->notify(x, XFRM_REPLAY_UPDATE);
+			xfrm_replay_notify(x, XFRM_REPLAY_UPDATE);
 	}
 
 	return err;
@@ -621,7 +635,7 @@ static int xfrm_replay_overflow_offload_bmp(struct xfrm_state *x, struct sk_buff
 		}
 
 		if (xfrm_aevent_is_on(net))
-			x->repl->notify(x, XFRM_REPLAY_UPDATE);
+			xfrm_replay_notify(x, XFRM_REPLAY_UPDATE);
 	}
 
 	return err;
@@ -670,7 +684,7 @@ static int xfrm_replay_overflow_offload_esn(struct xfrm_state *x, struct sk_buff
 		replay_esn->oseq = oseq;
 
 		if (xfrm_aevent_is_on(net))
-			x->repl->notify(x, XFRM_REPLAY_UPDATE);
+			xfrm_replay_notify(x, XFRM_REPLAY_UPDATE);
 	}
 
 	return err;
@@ -680,7 +694,6 @@ static const struct xfrm_replay xfrm_replay_legacy = {
 	.advance	= xfrm_replay_advance,
 	.check		= xfrm_replay_check,
 	.recheck	= xfrm_replay_check,
-	.notify		= xfrm_replay_notify,
 	.overflow	= xfrm_replay_overflow_offload,
 };
 
@@ -688,7 +701,6 @@ static const struct xfrm_replay xfrm_replay_bmp = {
 	.advance	= xfrm_replay_advance_bmp,
 	.check		= xfrm_replay_check_bmp,
 	.recheck	= xfrm_replay_check_bmp,
-	.notify		= xfrm_replay_notify_bmp,
 	.overflow	= xfrm_replay_overflow_offload_bmp,
 };
 
@@ -696,7 +708,6 @@ static const struct xfrm_replay xfrm_replay_esn = {
 	.advance	= xfrm_replay_advance_esn,
 	.check		= xfrm_replay_check_esn,
 	.recheck	= xfrm_replay_recheck_esn,
-	.notify		= xfrm_replay_notify_esn,
 	.overflow	= xfrm_replay_overflow_offload_esn,
 };
 #else
@@ -704,7 +715,6 @@ static const struct xfrm_replay xfrm_replay_legacy = {
 	.advance	= xfrm_replay_advance,
 	.check		= xfrm_replay_check,
 	.recheck	= xfrm_replay_check,
-	.notify		= xfrm_replay_notify,
 	.overflow	= xfrm_replay_overflow,
 };
 
@@ -712,7 +722,6 @@ static const struct xfrm_replay xfrm_replay_bmp = {
 	.advance	= xfrm_replay_advance_bmp,
 	.check		= xfrm_replay_check_bmp,
 	.recheck	= xfrm_replay_check_bmp,
-	.notify		= xfrm_replay_notify_bmp,
 	.overflow	= xfrm_replay_overflow_bmp,
 };
 
@@ -720,7 +729,6 @@ static const struct xfrm_replay xfrm_replay_esn = {
 	.advance	= xfrm_replay_advance_esn,
 	.check		= xfrm_replay_check_esn,
 	.recheck	= xfrm_replay_recheck_esn,
-	.notify		= xfrm_replay_notify_esn,
 	.overflow	= xfrm_replay_overflow_esn,
 };
 #endif
@@ -738,11 +746,14 @@ int xfrm_init_replay(struct xfrm_state *x)
 			if (replay_esn->replay_window == 0)
 				return -EINVAL;
 			x->repl = &xfrm_replay_esn;
+			x->repl_mode = XFRM_REPLAY_MODE_ESN;
 		} else {
 			x->repl = &xfrm_replay_bmp;
+			x->repl_mode = XFRM_REPLAY_MODE_BMP;
 		}
 	} else {
 		x->repl = &xfrm_replay_legacy;
+		x->repl_mode = XFRM_REPLAY_MODE_LEGACY;
 	}
 
 	return 0;
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 8be2d926acc2..c51bbcc263c7 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -2110,7 +2110,7 @@ static void xfrm_replay_timer_handler(struct timer_list *t)
 
 	if (x->km.state == XFRM_STATE_VALID) {
 		if (xfrm_aevent_is_on(xs_net(x)))
-			x->repl->notify(x, XFRM_REPLAY_TIMEOUT);
+			xfrm_replay_notify(x, XFRM_REPLAY_TIMEOUT);
 		else
 			x->xflags |= XFRM_TIME_DEFER;
 	}
-- 
2.26.2

[PATCH ipsec-next 2/6] xfrm: replay: get rid of duplicated notification code

[Florian Westphal]

After previous patch, we can consolidate some code:

xfrm_replay_notify, xfrm_replay_notify_bmp and _esn all contain the
same code at the end.

Remove it from xfrm_replay_notify_bmp/esn and reuse the one
in xfrm_replay_notify.

Signed-off-by: Florian Westphal <fw@strlen.de>
---
 net/xfrm/xfrm_replay.c | 22 ++++------------------
 1 file changed, 4 insertions(+), 18 deletions(-)

diff --git a/net/xfrm/xfrm_replay.c b/net/xfrm/xfrm_replay.c
index e42a7afb8ee5..fac2f3af4c1a 100644
--- a/net/xfrm/xfrm_replay.c
+++ b/net/xfrm/xfrm_replay.c
@@ -56,10 +56,10 @@ void xfrm_replay_notify(struct xfrm_state *x, int event)
 		break;
 	case XFRM_REPLAY_MODE_BMP:
 		xfrm_replay_notify_bmp(x, event);
-		return;
+		goto notify;
 	case XFRM_REPLAY_MODE_ESN:
 		xfrm_replay_notify_esn(x, event);
-		return;
+		goto notify;
 	}
 
 	switch (event) {
@@ -86,6 +86,8 @@ void xfrm_replay_notify(struct xfrm_state *x, int event)
 	}
 
 	memcpy(&x->preplay, &x->replay, sizeof(struct xfrm_replay_state));
+
+notify:
 	c.event = XFRM_MSG_NEWAE;
 	c.data.aevent = event;
 	km_state_notify(x, &c);
@@ -290,7 +292,6 @@ static void xfrm_replay_advance_bmp(struct xfrm_state *x, __be32 net_seq)
 
 static void xfrm_replay_notify_bmp(struct xfrm_state *x, int event)
 {
-	struct km_event c;
 	struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
 	struct xfrm_replay_state_esn *preplay_esn = x->preplay_esn;
 
@@ -330,19 +331,11 @@ static void xfrm_replay_notify_bmp(struct xfrm_state *x, int event)
 
 	memcpy(x->preplay_esn, x->replay_esn,
 	       xfrm_replay_state_esn_len(replay_esn));
-	c.event = XFRM_MSG_NEWAE;
-	c.data.aevent = event;
-	km_state_notify(x, &c);
-
-	if (x->replay_maxage &&
-	    !mod_timer(&x->rtimer, jiffies + x->replay_maxage))
-		x->xflags &= ~XFRM_TIME_DEFER;
 }
 
 static void xfrm_replay_notify_esn(struct xfrm_state *x, int event)
 {
 	u32 seq_diff, oseq_diff;
-	struct km_event c;
 	struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
 	struct xfrm_replay_state_esn *preplay_esn = x->preplay_esn;
 
@@ -396,13 +389,6 @@ static void xfrm_replay_notify_esn(struct xfrm_state *x, int event)
 
 	memcpy(x->preplay_esn, x->replay_esn,
 	       xfrm_replay_state_esn_len(replay_esn));
-	c.event = XFRM_MSG_NEWAE;
-	c.data.aevent = event;
-	km_state_notify(x, &c);
-
-	if (x->replay_maxage &&
-	    !mod_timer(&x->rtimer, jiffies + x->replay_maxage))
-		x->xflags &= ~XFRM_TIME_DEFER;
 }
 
 static int xfrm_replay_overflow_esn(struct xfrm_state *x, struct sk_buff *skb)
-- 
2.26.2

[PATCH ipsec-next 3/6] xfrm: replay: remove advance indirection

[Florian Westphal]

Similar to other patches: add a new helper to avoid
an indirection.

Signed-off-by: Florian Westphal <fw@strlen.de>
---
 include/net/xfrm.h     |  2 +-
 net/xfrm/xfrm_input.c  |  2 +-
 net/xfrm/xfrm_replay.c | 24 ++++++++++++++----------
 3 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index ed105257c5a8..78bbfd370e34 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -304,7 +304,6 @@ struct km_event {
 };
 
 struct xfrm_replay {
-	void	(*advance)(struct xfrm_state *x, __be32 net_seq);
 	int	(*check)(struct xfrm_state *x,
 			 struct sk_buff *skb,
 			 __be32 net_seq);
@@ -1719,6 +1718,7 @@ static inline int xfrm_policy_id2dir(u32 index)
 }
 
 #ifdef CONFIG_XFRM
+void xfrm_replay_advance(struct xfrm_state *x, __be32 net_seq);
 void xfrm_replay_notify(struct xfrm_state *x, int event);
 
 static inline int xfrm_aevent_is_on(struct net *net)
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index bd984ff17c2d..b4b559b35cf1 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -663,7 +663,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 			goto drop_unlock;
 		}
 
-		x->repl->advance(x, seq);
+		xfrm_replay_advance(x, seq);
 
 		x->curlft.bytes += skb->len;
 		x->curlft.packets++;
diff --git a/net/xfrm/xfrm_replay.c b/net/xfrm/xfrm_replay.c
index fac2f3af4c1a..8a99316d8d7d 100644
--- a/net/xfrm/xfrm_replay.c
+++ b/net/xfrm/xfrm_replay.c
@@ -151,11 +151,23 @@ static int xfrm_replay_check(struct xfrm_state *x,
 	return -EINVAL;
 }
 
-static void xfrm_replay_advance(struct xfrm_state *x, __be32 net_seq)
+static void xfrm_replay_advance_bmp(struct xfrm_state *x, u32 seq);
+static void xfrm_replay_advance_esn(struct xfrm_state *x, __be32 net_seq);
+
+void xfrm_replay_advance(struct xfrm_state *x, __be32 net_seq)
 {
 	u32 diff;
 	u32 seq = ntohl(net_seq);
 
+	switch (x->repl_mode) {
+	case XFRM_REPLAY_MODE_LEGACY:
+		break;
+	case XFRM_REPLAY_MODE_BMP:
+		return xfrm_replay_advance_bmp(x, seq);
+	case XFRM_REPLAY_MODE_ESN:
+		return xfrm_replay_advance_esn(x, net_seq);
+	}
+
 	if (!x->props.replay_window)
 		return;
 
@@ -242,12 +254,11 @@ static int xfrm_replay_check_bmp(struct xfrm_state *x,
 	return -EINVAL;
 }
 
-static void xfrm_replay_advance_bmp(struct xfrm_state *x, __be32 net_seq)
+static void xfrm_replay_advance_bmp(struct xfrm_state *x, u32 seq)
 {
 	unsigned int bitnr, nr, i;
 	u32 diff;
 	struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
-	u32 seq = ntohl(net_seq);
 	u32 pos;
 
 	if (!replay_esn->replay_window)
@@ -501,7 +512,6 @@ static void xfrm_replay_advance_esn(struct xfrm_state *x, __be32 net_seq)
 	if (!replay_esn->replay_window)
 		return;
 
-	seq = ntohl(net_seq);
 	pos = (replay_esn->seq - 1) % replay_esn->replay_window;
 	seq_hi = xfrm_replay_seqhi(x, net_seq);
 	wrap = seq_hi - replay_esn->seq_hi;
@@ -677,42 +687,36 @@ static int xfrm_replay_overflow_offload_esn(struct xfrm_state *x, struct sk_buff
 }
 
 static const struct xfrm_replay xfrm_replay_legacy = {
-	.advance	= xfrm_replay_advance,
 	.check		= xfrm_replay_check,
 	.recheck	= xfrm_replay_check,
 	.overflow	= xfrm_replay_overflow_offload,
 };
 
 static const struct xfrm_replay xfrm_replay_bmp = {
-	.advance	= xfrm_replay_advance_bmp,
 	.check		= xfrm_replay_check_bmp,
 	.recheck	= xfrm_replay_check_bmp,
 	.overflow	= xfrm_replay_overflow_offload_bmp,
 };
 
 static const struct xfrm_replay xfrm_replay_esn = {
-	.advance	= xfrm_replay_advance_esn,
 	.check		= xfrm_replay_check_esn,
 	.recheck	= xfrm_replay_recheck_esn,
 	.overflow	= xfrm_replay_overflow_offload_esn,
 };
 #else
 static const struct xfrm_replay xfrm_replay_legacy = {
-	.advance	= xfrm_replay_advance,
 	.check		= xfrm_replay_check,
 	.recheck	= xfrm_replay_check,
 	.overflow	= xfrm_replay_overflow,
 };
 
 static const struct xfrm_replay xfrm_replay_bmp = {
-	.advance	= xfrm_replay_advance_bmp,
 	.check		= xfrm_replay_check_bmp,
 	.recheck	= xfrm_replay_check_bmp,
 	.overflow	= xfrm_replay_overflow_bmp,
 };
 
 static const struct xfrm_replay xfrm_replay_esn = {
-	.advance	= xfrm_replay_advance_esn,
 	.check		= xfrm_replay_check_esn,
 	.recheck	= xfrm_replay_recheck_esn,
 	.overflow	= xfrm_replay_overflow_esn,
-- 
2.26.2

Re: [PATCH ipsec-next 3/6] xfrm: replay: remove advance indirection

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 5866 bytes --]

Hi Florian,

I love your patch! Perhaps something to improve:

[auto build test WARNING on ipsec-next/master]

url:    https://github.com/0day-ci/linux/commits/Florian-Westphal/xfrm-remove-xfrm-replay-indirections/20200624-035102
base:   https://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next.git master
config: mips-malta_defconfig (attached as .config)
compiler: mipsel-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=mips 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

Note: it may well be a FALSE warning. FWIW you are at least aware of it now.
http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings

All warnings (new ones prefixed by >>):

   net/xfrm/xfrm_replay.c: In function 'xfrm_replay_advance':
>> net/xfrm/xfrm_replay.c:519:13: warning: 'seq' may be used uninitialized in this function [-Wmaybe-uninitialized]
     519 |  if ((!wrap && seq > replay_esn->seq) || wrap > 0) {
         |      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
   net/xfrm/xfrm_replay.c:509:17: note: 'seq' was declared here
     509 |  u32 diff, pos, seq, seq_hi;
         |                 ^~~

vim +/seq +519 net/xfrm/xfrm_replay.c

3b59df46a449ec9 Steffen Klassert 2012-09-04  504  
2cd084678fc1eb7 Steffen Klassert 2011-03-08  505  static void xfrm_replay_advance_esn(struct xfrm_state *x, __be32 net_seq)
2cd084678fc1eb7 Steffen Klassert 2011-03-08  506  {
2cd084678fc1eb7 Steffen Klassert 2011-03-08  507  	unsigned int bitnr, nr, i;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  508  	int wrap;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  509  	u32 diff, pos, seq, seq_hi;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  510  	struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  511  
2cd084678fc1eb7 Steffen Klassert 2011-03-08  512  	if (!replay_esn->replay_window)
2cd084678fc1eb7 Steffen Klassert 2011-03-08  513  		return;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  514  
2cd084678fc1eb7 Steffen Klassert 2011-03-08  515  	pos = (replay_esn->seq - 1) % replay_esn->replay_window;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  516  	seq_hi = xfrm_replay_seqhi(x, net_seq);
2cd084678fc1eb7 Steffen Klassert 2011-03-08  517  	wrap = seq_hi - replay_esn->seq_hi;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  518  
2cd084678fc1eb7 Steffen Klassert 2011-03-08 @519  	if ((!wrap && seq > replay_esn->seq) || wrap > 0) {
2cd084678fc1eb7 Steffen Klassert 2011-03-08  520  		if (likely(!wrap))
2cd084678fc1eb7 Steffen Klassert 2011-03-08  521  			diff = seq - replay_esn->seq;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  522  		else
2cd084678fc1eb7 Steffen Klassert 2011-03-08  523  			diff = ~replay_esn->seq + seq + 1;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  524  
2cd084678fc1eb7 Steffen Klassert 2011-03-08  525  		if (diff < replay_esn->replay_window) {
2cd084678fc1eb7 Steffen Klassert 2011-03-08  526  			for (i = 1; i < diff; i++) {
2cd084678fc1eb7 Steffen Klassert 2011-03-08  527  				bitnr = (pos + i) % replay_esn->replay_window;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  528  				nr = bitnr >> 5;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  529  				bitnr = bitnr & 0x1F;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  530  				replay_esn->bmp[nr] &=  ~(1U << bitnr);
2cd084678fc1eb7 Steffen Klassert 2011-03-08  531  			}
2cd084678fc1eb7 Steffen Klassert 2011-03-08  532  		} else {
e756682c8baa47d Steffen Klassert 2011-06-05  533  			nr = (replay_esn->replay_window - 1) >> 5;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  534  			for (i = 0; i <= nr; i++)
2cd084678fc1eb7 Steffen Klassert 2011-03-08  535  				replay_esn->bmp[i] = 0;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  536  		}
2cd084678fc1eb7 Steffen Klassert 2011-03-08  537  
1d9743745bf5ba3 Steffen Klassert 2011-10-11  538  		bitnr = (pos + diff) % replay_esn->replay_window;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  539  		replay_esn->seq = seq;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  540  
2cd084678fc1eb7 Steffen Klassert 2011-03-08  541  		if (unlikely(wrap > 0))
2cd084678fc1eb7 Steffen Klassert 2011-03-08  542  			replay_esn->seq_hi++;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  543  	} else {
2cd084678fc1eb7 Steffen Klassert 2011-03-08  544  		diff = replay_esn->seq - seq;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  545  
1d9743745bf5ba3 Steffen Klassert 2011-10-11  546  		if (pos >= diff)
2cd084678fc1eb7 Steffen Klassert 2011-03-08  547  			bitnr = (pos - diff) % replay_esn->replay_window;
1d9743745bf5ba3 Steffen Klassert 2011-10-11  548  		else
2cd084678fc1eb7 Steffen Klassert 2011-03-08  549  			bitnr = replay_esn->replay_window - (diff - pos);
1d9743745bf5ba3 Steffen Klassert 2011-10-11  550  	}
1d9743745bf5ba3 Steffen Klassert 2011-10-11  551  
50bd870a9e5cca9 Yossef Efraim    2018-01-14  552  	xfrm_dev_state_advance_esn(x);
50bd870a9e5cca9 Yossef Efraim    2018-01-14  553  
2cd084678fc1eb7 Steffen Klassert 2011-03-08  554  	nr = bitnr >> 5;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  555  	bitnr = bitnr & 0x1F;
2cd084678fc1eb7 Steffen Klassert 2011-03-08  556  	replay_esn->bmp[nr] |= (1U << bitnr);
2cd084678fc1eb7 Steffen Klassert 2011-03-08  557  
2cd084678fc1eb7 Steffen Klassert 2011-03-08  558  	if (xfrm_aevent_is_on(xs_net(x)))
f7d9410c27544ca Florian Westphal 2020-06-23  559  		xfrm_replay_notify(x, XFRM_REPLAY_UPDATE);
2cd084678fc1eb7 Steffen Klassert 2011-03-08  560  }
2cd084678fc1eb7 Steffen Klassert 2011-03-08  561  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 20401 bytes --]

Re: [PATCH ipsec-next 3/6] xfrm: replay: remove advance indirection

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 5855 bytes --]

Hi Florian,

I love your patch! Perhaps something to improve:

[auto build test WARNING on ipsec-next/master]

url:    https://github.com/0day-ci/linux/commits/Florian-Westphal/xfrm-remove-xfrm-replay-indirections/20200624-035102
base:   https://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next.git master
config: x86_64-allyesconfig (attached as .config)
compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 1d4c87335d5236ea1f35937e1014980ba961ae34)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install x86_64 cross compiling tool for clang build
        # apt-get install binutils-x86-64-linux-gnu
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> net/xfrm/xfrm_replay.c:519:16: warning: variable 'seq' is uninitialized when used here [-Wuninitialized]
           if ((!wrap && seq > replay_esn->seq) || wrap > 0) {
                         ^~~
   net/xfrm/xfrm_replay.c:509:20: note: initialize the variable 'seq' to silence this warning
           u32 diff, pos, seq, seq_hi;
                             ^
                              = 0
   1 warning generated.

vim +/seq +519 net/xfrm/xfrm_replay.c

3b59df46a449ec Steffen Klassert 2012-09-04  504  
2cd084678fc1eb Steffen Klassert 2011-03-08  505  static void xfrm_replay_advance_esn(struct xfrm_state *x, __be32 net_seq)
2cd084678fc1eb Steffen Klassert 2011-03-08  506  {
2cd084678fc1eb Steffen Klassert 2011-03-08  507  	unsigned int bitnr, nr, i;
2cd084678fc1eb Steffen Klassert 2011-03-08  508  	int wrap;
2cd084678fc1eb Steffen Klassert 2011-03-08  509  	u32 diff, pos, seq, seq_hi;
2cd084678fc1eb Steffen Klassert 2011-03-08  510  	struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
2cd084678fc1eb Steffen Klassert 2011-03-08  511  
2cd084678fc1eb Steffen Klassert 2011-03-08  512  	if (!replay_esn->replay_window)
2cd084678fc1eb Steffen Klassert 2011-03-08  513  		return;
2cd084678fc1eb Steffen Klassert 2011-03-08  514  
2cd084678fc1eb Steffen Klassert 2011-03-08  515  	pos = (replay_esn->seq - 1) % replay_esn->replay_window;
2cd084678fc1eb Steffen Klassert 2011-03-08  516  	seq_hi = xfrm_replay_seqhi(x, net_seq);
2cd084678fc1eb Steffen Klassert 2011-03-08  517  	wrap = seq_hi - replay_esn->seq_hi;
2cd084678fc1eb Steffen Klassert 2011-03-08  518  
2cd084678fc1eb Steffen Klassert 2011-03-08 @519  	if ((!wrap && seq > replay_esn->seq) || wrap > 0) {
2cd084678fc1eb Steffen Klassert 2011-03-08  520  		if (likely(!wrap))
2cd084678fc1eb Steffen Klassert 2011-03-08  521  			diff = seq - replay_esn->seq;
2cd084678fc1eb Steffen Klassert 2011-03-08  522  		else
2cd084678fc1eb Steffen Klassert 2011-03-08  523  			diff = ~replay_esn->seq + seq + 1;
2cd084678fc1eb Steffen Klassert 2011-03-08  524  
2cd084678fc1eb Steffen Klassert 2011-03-08  525  		if (diff < replay_esn->replay_window) {
2cd084678fc1eb Steffen Klassert 2011-03-08  526  			for (i = 1; i < diff; i++) {
2cd084678fc1eb Steffen Klassert 2011-03-08  527  				bitnr = (pos + i) % replay_esn->replay_window;
2cd084678fc1eb Steffen Klassert 2011-03-08  528  				nr = bitnr >> 5;
2cd084678fc1eb Steffen Klassert 2011-03-08  529  				bitnr = bitnr & 0x1F;
2cd084678fc1eb Steffen Klassert 2011-03-08  530  				replay_esn->bmp[nr] &=  ~(1U << bitnr);
2cd084678fc1eb Steffen Klassert 2011-03-08  531  			}
2cd084678fc1eb Steffen Klassert 2011-03-08  532  		} else {
e756682c8baa47 Steffen Klassert 2011-06-05  533  			nr = (replay_esn->replay_window - 1) >> 5;
2cd084678fc1eb Steffen Klassert 2011-03-08  534  			for (i = 0; i <= nr; i++)
2cd084678fc1eb Steffen Klassert 2011-03-08  535  				replay_esn->bmp[i] = 0;
2cd084678fc1eb Steffen Klassert 2011-03-08  536  		}
2cd084678fc1eb Steffen Klassert 2011-03-08  537  
1d9743745bf5ba Steffen Klassert 2011-10-11  538  		bitnr = (pos + diff) % replay_esn->replay_window;
2cd084678fc1eb Steffen Klassert 2011-03-08  539  		replay_esn->seq = seq;
2cd084678fc1eb Steffen Klassert 2011-03-08  540  
2cd084678fc1eb Steffen Klassert 2011-03-08  541  		if (unlikely(wrap > 0))
2cd084678fc1eb Steffen Klassert 2011-03-08  542  			replay_esn->seq_hi++;
2cd084678fc1eb Steffen Klassert 2011-03-08  543  	} else {
2cd084678fc1eb Steffen Klassert 2011-03-08  544  		diff = replay_esn->seq - seq;
2cd084678fc1eb Steffen Klassert 2011-03-08  545  
1d9743745bf5ba Steffen Klassert 2011-10-11  546  		if (pos >= diff)
2cd084678fc1eb Steffen Klassert 2011-03-08  547  			bitnr = (pos - diff) % replay_esn->replay_window;
1d9743745bf5ba Steffen Klassert 2011-10-11  548  		else
2cd084678fc1eb Steffen Klassert 2011-03-08  549  			bitnr = replay_esn->replay_window - (diff - pos);
1d9743745bf5ba Steffen Klassert 2011-10-11  550  	}
1d9743745bf5ba Steffen Klassert 2011-10-11  551  
50bd870a9e5cca Yossef Efraim    2018-01-14  552  	xfrm_dev_state_advance_esn(x);
50bd870a9e5cca Yossef Efraim    2018-01-14  553  
2cd084678fc1eb Steffen Klassert 2011-03-08  554  	nr = bitnr >> 5;
2cd084678fc1eb Steffen Klassert 2011-03-08  555  	bitnr = bitnr & 0x1F;
2cd084678fc1eb Steffen Klassert 2011-03-08  556  	replay_esn->bmp[nr] |= (1U << bitnr);
2cd084678fc1eb Steffen Klassert 2011-03-08  557  
2cd084678fc1eb Steffen Klassert 2011-03-08  558  	if (xfrm_aevent_is_on(xs_net(x)))
f7d9410c27544c Florian Westphal 2020-06-23  559  		xfrm_replay_notify(x, XFRM_REPLAY_UPDATE);
2cd084678fc1eb Steffen Klassert 2011-03-08  560  }
2cd084678fc1eb Steffen Klassert 2011-03-08  561  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 73984 bytes --]

[PATCH ipsec-next 4/6] xfrm: replay: remove recheck indirection

[Florian Westphal]

Adds new xfrm_replay_recheck() helper and calls it from
xfrm input path instead of the indirection.

Signed-off-by: Florian Westphal <fw@strlen.de>
---
 include/net/xfrm.h     |  4 +---
 net/xfrm/xfrm_input.c  |  2 +-
 net/xfrm/xfrm_replay.c | 22 ++++++++++++++++------
 3 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 78bbfd370e34..7c0b69e00128 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -307,9 +307,6 @@ struct xfrm_replay {
 	int	(*check)(struct xfrm_state *x,
 			 struct sk_buff *skb,
 			 __be32 net_seq);
-	int	(*recheck)(struct xfrm_state *x,
-			   struct sk_buff *skb,
-			   __be32 net_seq);
 	int	(*overflow)(struct xfrm_state *x, struct sk_buff *skb);
 };
 
@@ -1720,6 +1717,7 @@ static inline int xfrm_policy_id2dir(u32 index)
 #ifdef CONFIG_XFRM
 void xfrm_replay_advance(struct xfrm_state *x, __be32 net_seq);
 void xfrm_replay_notify(struct xfrm_state *x, int event);
+int xfrm_replay_recheck(struct xfrm_state *x, struct sk_buff *skb, __be32 net_seq);
 
 static inline int xfrm_aevent_is_on(struct net *net)
 {
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index b4b559b35cf1..005d8e9c5df4 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -658,7 +658,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 		/* only the first xfrm gets the encap type */
 		encap_type = 0;
 
-		if (async && x->repl->recheck(x, skb, seq)) {
+		if (async && xfrm_replay_recheck(x, skb, seq)) {
 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
 			goto drop_unlock;
 		}
diff --git a/net/xfrm/xfrm_replay.c b/net/xfrm/xfrm_replay.c
index 8a99316d8d7d..8917b2ede3cd 100644
--- a/net/xfrm/xfrm_replay.c
+++ b/net/xfrm/xfrm_replay.c
@@ -502,6 +502,22 @@ static int xfrm_replay_recheck_esn(struct xfrm_state *x,
 	return xfrm_replay_check_esn(x, skb, net_seq);
 }
 
+int xfrm_replay_recheck(struct xfrm_state *x,
+			struct sk_buff *skb, __be32 net_seq)
+{
+	switch (x->repl_mode) {
+	case XFRM_REPLAY_MODE_LEGACY:
+		break;
+	case XFRM_REPLAY_MODE_BMP:
+		/* no special recheck treatment */
+		return xfrm_replay_check_bmp(x, skb, net_seq);
+	case XFRM_REPLAY_MODE_ESN:
+		return xfrm_replay_recheck_esn(x, skb, net_seq);
+	}
+
+	return xfrm_replay_check(x, skb, net_seq);
+}
+
 static void xfrm_replay_advance_esn(struct xfrm_state *x, __be32 net_seq)
 {
 	unsigned int bitnr, nr, i;
@@ -688,37 +704,31 @@ static int xfrm_replay_overflow_offload_esn(struct xfrm_state *x, struct sk_buff
 
 static const struct xfrm_replay xfrm_replay_legacy = {
 	.check		= xfrm_replay_check,
-	.recheck	= xfrm_replay_check,
 	.overflow	= xfrm_replay_overflow_offload,
 };
 
 static const struct xfrm_replay xfrm_replay_bmp = {
 	.check		= xfrm_replay_check_bmp,
-	.recheck	= xfrm_replay_check_bmp,
 	.overflow	= xfrm_replay_overflow_offload_bmp,
 };
 
 static const struct xfrm_replay xfrm_replay_esn = {
 	.check		= xfrm_replay_check_esn,
-	.recheck	= xfrm_replay_recheck_esn,
 	.overflow	= xfrm_replay_overflow_offload_esn,
 };
 #else
 static const struct xfrm_replay xfrm_replay_legacy = {
 	.check		= xfrm_replay_check,
-	.recheck	= xfrm_replay_check,
 	.overflow	= xfrm_replay_overflow,
 };
 
 static const struct xfrm_replay xfrm_replay_bmp = {
 	.check		= xfrm_replay_check_bmp,
-	.recheck	= xfrm_replay_check_bmp,
 	.overflow	= xfrm_replay_overflow_bmp,
 };
 
 static const struct xfrm_replay xfrm_replay_esn = {
 	.check		= xfrm_replay_check_esn,
-	.recheck	= xfrm_replay_recheck_esn,
 	.overflow	= xfrm_replay_overflow_esn,
 };
 #endif
-- 
2.26.2

[PATCH ipsec-next 5/6] xfrm: replay: avoid replay indirection

[Florian Westphal]

Add and use xfrm_replay_check helper instead of indirection.

Signed-off-by: Florian Westphal <fw@strlen.de>
---
 include/net/xfrm.h     |  4 +---
 net/xfrm/xfrm_input.c  |  2 +-
 net/xfrm/xfrm_replay.c | 27 ++++++++++++++++++---------
 3 files changed, 20 insertions(+), 13 deletions(-)

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 7c0b69e00128..008b564cb126 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -304,9 +304,6 @@ struct km_event {
 };
 
 struct xfrm_replay {
-	int	(*check)(struct xfrm_state *x,
-			 struct sk_buff *skb,
-			 __be32 net_seq);
 	int	(*overflow)(struct xfrm_state *x, struct sk_buff *skb);
 };
 
@@ -1716,6 +1713,7 @@ static inline int xfrm_policy_id2dir(u32 index)
 
 #ifdef CONFIG_XFRM
 void xfrm_replay_advance(struct xfrm_state *x, __be32 net_seq);
+int xfrm_replay_check(struct xfrm_state *x, struct sk_buff *skb, __be32 net_seq);
 void xfrm_replay_notify(struct xfrm_state *x, int event);
 int xfrm_replay_recheck(struct xfrm_state *x, struct sk_buff *skb, __be32 net_seq);
 
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index 005d8e9c5df4..694adc6e9286 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -610,7 +610,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 			goto drop_unlock;
 		}
 
-		if (x->repl->check(x, skb, seq)) {
+		if (xfrm_replay_check(x, skb, seq)) {
 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
 			goto drop_unlock;
 		}
diff --git a/net/xfrm/xfrm_replay.c b/net/xfrm/xfrm_replay.c
index 8917b2ede3cd..3cbe478d86e7 100644
--- a/net/xfrm/xfrm_replay.c
+++ b/net/xfrm/xfrm_replay.c
@@ -119,8 +119,8 @@ static int xfrm_replay_overflow(struct xfrm_state *x, struct sk_buff *skb)
 	return err;
 }
 
-static int xfrm_replay_check(struct xfrm_state *x,
-		      struct sk_buff *skb, __be32 net_seq)
+static int xfrm_replay_check_legacy(struct xfrm_state *x,
+				    struct sk_buff *skb, __be32 net_seq)
 {
 	u32 diff;
 	u32 seq = ntohl(net_seq);
@@ -490,6 +490,21 @@ static int xfrm_replay_check_esn(struct xfrm_state *x,
 	return -EINVAL;
 }
 
+int xfrm_replay_check(struct xfrm_state *x,
+		      struct sk_buff *skb, __be32 net_seq)
+{
+	switch (x->repl_mode) {
+	case XFRM_REPLAY_MODE_LEGACY:
+		break;
+	case XFRM_REPLAY_MODE_BMP:
+		return xfrm_replay_check_bmp(x, skb, net_seq);
+	case XFRM_REPLAY_MODE_ESN:
+		return xfrm_replay_check_esn(x, skb, net_seq);
+	}
+
+	return xfrm_replay_check_legacy(x, skb, net_seq);
+}
+
 static int xfrm_replay_recheck_esn(struct xfrm_state *x,
 				   struct sk_buff *skb, __be32 net_seq)
 {
@@ -515,7 +530,7 @@ int xfrm_replay_recheck(struct xfrm_state *x,
 		return xfrm_replay_recheck_esn(x, skb, net_seq);
 	}
 
-	return xfrm_replay_check(x, skb, net_seq);
+	return xfrm_replay_check_legacy(x, skb, net_seq);
 }
 
 static void xfrm_replay_advance_esn(struct xfrm_state *x, __be32 net_seq)
@@ -703,32 +718,26 @@ static int xfrm_replay_overflow_offload_esn(struct xfrm_state *x, struct sk_buff
 }
 
 static const struct xfrm_replay xfrm_replay_legacy = {
-	.check		= xfrm_replay_check,
 	.overflow	= xfrm_replay_overflow_offload,
 };
 
 static const struct xfrm_replay xfrm_replay_bmp = {
-	.check		= xfrm_replay_check_bmp,
 	.overflow	= xfrm_replay_overflow_offload_bmp,
 };
 
 static const struct xfrm_replay xfrm_replay_esn = {
-	.check		= xfrm_replay_check_esn,
 	.overflow	= xfrm_replay_overflow_offload_esn,
 };
 #else
 static const struct xfrm_replay xfrm_replay_legacy = {
-	.check		= xfrm_replay_check,
 	.overflow	= xfrm_replay_overflow,
 };
 
 static const struct xfrm_replay xfrm_replay_bmp = {
-	.check		= xfrm_replay_check_bmp,
 	.overflow	= xfrm_replay_overflow_bmp,
 };
 
 static const struct xfrm_replay xfrm_replay_esn = {
-	.check		= xfrm_replay_check_esn,
 	.overflow	= xfrm_replay_overflow_esn,
 };
 #endif
-- 
2.26.2

[PATCH ipsec-next 6/6] xfrm: replay: remove last replay indirection

[Florian Westphal]

This replaces the overflow indirection with the new xfrm_replay_overflow
helper.  After this, the 'repl' pointer in xfrm_state is no longer
needed and can be removed as well.

xfrm_replay_overflow() is added in two incarnations, one is used
when the kernel is configured with xfrm offload enabled, the other
when its disabled.

Signed-off-by: Florian Westphal <fw@strlen.de>
---
 include/net/xfrm.h     |  8 +------
 net/xfrm/xfrm_output.c |  2 +-
 net/xfrm/xfrm_replay.c | 51 +++++++++++++++++++++---------------------
 3 files changed, 28 insertions(+), 33 deletions(-)

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 008b564cb126..c0f3e8a3fdd0 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -219,9 +219,6 @@ struct xfrm_state {
 	struct xfrm_replay_state preplay;
 	struct xfrm_replay_state_esn *preplay_esn;
 
-	/* The functions for replay detection. */
-	const struct xfrm_replay *repl;
-
 	/* replay detection mode */
 	enum xfrm_replay_mode    repl_mode;
 	/* internal flag that only holds state for delayed aevent at the
@@ -303,10 +300,6 @@ struct km_event {
 	struct net *net;
 };
 
-struct xfrm_replay {
-	int	(*overflow)(struct xfrm_state *x, struct sk_buff *skb);
-};
-
 struct xfrm_if_cb {
 	struct xfrm_if	*(*decode_session)(struct sk_buff *skb,
 					   unsigned short family);
@@ -1715,6 +1708,7 @@ static inline int xfrm_policy_id2dir(u32 index)
 void xfrm_replay_advance(struct xfrm_state *x, __be32 net_seq);
 int xfrm_replay_check(struct xfrm_state *x, struct sk_buff *skb, __be32 net_seq);
 void xfrm_replay_notify(struct xfrm_state *x, int event);
+int xfrm_replay_overflow(struct xfrm_state *x, struct sk_buff *skb);
 int xfrm_replay_recheck(struct xfrm_state *x, struct sk_buff *skb, __be32 net_seq);
 
 static inline int xfrm_aevent_is_on(struct net *net)
diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
index e4c23f69f69f..8893a37690ad 100644
--- a/net/xfrm/xfrm_output.c
+++ b/net/xfrm/xfrm_output.c
@@ -448,7 +448,7 @@ static int xfrm_output_one(struct sk_buff *skb, int err)
 			goto error;
 		}
 
-		err = x->repl->overflow(x, skb);
+		err = xfrm_replay_overflow(x, skb);
 		if (err) {
 			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATESEQERROR);
 			goto error;
diff --git a/net/xfrm/xfrm_replay.c b/net/xfrm/xfrm_replay.c
index 3cbe478d86e7..2715fda44697 100644
--- a/net/xfrm/xfrm_replay.c
+++ b/net/xfrm/xfrm_replay.c
@@ -97,7 +97,7 @@ void xfrm_replay_notify(struct xfrm_state *x, int event)
 		x->xflags &= ~XFRM_TIME_DEFER;
 }
 
-static int xfrm_replay_overflow(struct xfrm_state *x, struct sk_buff *skb)
+static int __xfrm_replay_overflow(struct xfrm_state *x, struct sk_buff *skb)
 {
 	int err = 0;
 	struct net *net = xs_net(x);
@@ -599,7 +599,7 @@ static int xfrm_replay_overflow_offload(struct xfrm_state *x, struct sk_buff *sk
 	__u32 oseq = x->replay.oseq;
 
 	if (!xo)
-		return xfrm_replay_overflow(x, skb);
+		return __xfrm_replay_overflow(x, skb);
 
 	if (x->type->flags & XFRM_TYPE_REPLAY_PROT) {
 		if (!skb_is_gso(skb)) {
@@ -717,29 +717,33 @@ static int xfrm_replay_overflow_offload_esn(struct xfrm_state *x, struct sk_buff
 	return err;
 }
 
-static const struct xfrm_replay xfrm_replay_legacy = {
-	.overflow	= xfrm_replay_overflow_offload,
-};
-
-static const struct xfrm_replay xfrm_replay_bmp = {
-	.overflow	= xfrm_replay_overflow_offload_bmp,
-};
+int xfrm_replay_overflow(struct xfrm_state *x, struct sk_buff *skb)
+{
+	switch (x->repl_mode) {
+	case XFRM_REPLAY_MODE_LEGACY:
+		break;
+	case XFRM_REPLAY_MODE_BMP:
+		return xfrm_replay_overflow_offload_bmp(x, skb);
+	case XFRM_REPLAY_MODE_ESN:
+		return xfrm_replay_overflow_offload_esn(x, skb);
+	}
 
-static const struct xfrm_replay xfrm_replay_esn = {
-	.overflow	= xfrm_replay_overflow_offload_esn,
-};
+	return xfrm_replay_overflow_offload(x, skb);
+}
 #else
-static const struct xfrm_replay xfrm_replay_legacy = {
-	.overflow	= xfrm_replay_overflow,
-};
-
-static const struct xfrm_replay xfrm_replay_bmp = {
-	.overflow	= xfrm_replay_overflow_bmp,
-};
+int xfrm_replay_overflow(struct xfrm_state *x, struct sk_buff *skb)
+{
+	switch (x->repl_mode) {
+	case XFRM_REPLAY_MODE_LEGACY:
+		break;
+	case XFRM_REPLAY_MODE_BMP:
+		return xfrm_replay_overflow_bmp(x, skb);
+	case XFRM_REPLAY_MODE_ESN:
+		return xfrm_replay_overflow_esn(x, skb);
+	}
 
-static const struct xfrm_replay xfrm_replay_esn = {
-	.overflow	= xfrm_replay_overflow_esn,
-};
+	return __xfrm_replay_overflow(x, skb);
+}
 #endif
 
 int xfrm_init_replay(struct xfrm_state *x)
@@ -754,14 +758,11 @@ int xfrm_init_replay(struct xfrm_state *x)
 		if (x->props.flags & XFRM_STATE_ESN) {
 			if (replay_esn->replay_window == 0)
 				return -EINVAL;
-			x->repl = &xfrm_replay_esn;
 			x->repl_mode = XFRM_REPLAY_MODE_ESN;
 		} else {
-			x->repl = &xfrm_replay_bmp;
 			x->repl_mode = XFRM_REPLAY_MODE_BMP;
 		}
 	} else {
-		x->repl = &xfrm_replay_legacy;
 		x->repl_mode = XFRM_REPLAY_MODE_LEGACY;
 	}
 
-- 
2.26.2