提交 · 90f5dfcc6afafcc3e1c18298143c1213b071990d · openanolis / cloud-kernel

26 12月, 2008 20 次提交

drivers/net: Remove redundant test · 90f5dfcc

由 Julia Lawall 提交于 12月 25, 2008

In each case, ap is checked not to be NULL a few lines before.

A simplified version of the semantic patch that makes this change is as
follows: (http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r exists@
local idexpression x;
expression E;
position p1,p2;
@@

if (x@p1 == NULL || ...) { ... when forall
   return ...; }
... when != \(x=E\|x--\|x++\|--x\|++x\|x-=E\|x+=E\|x|=E\|x&=E\|&x\)
(
x@p2 == NULL
|
x@p2 != NULL
)

// another path to the test that is not through p1?
@s exists@
local idexpression r.x;
position r.p1,r.p2;
@@

... when != x@p1
(
x@p2 == NULL
|
x@p2 != NULL
)

@fix depends on !s@
position r.p1,r.p2;
expression x,E;
statement S1,S2;
@@

(
- if ((x@p2 != NULL) || ...)
  S1
|
- if ((x@p2 == NULL) && ...) S1
|
- BUG_ON(x@p2 == NULL);
)
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

90f5dfcc

drivers/net/ehea: Remove redundant test · 662f44af

由 Julia Lawall 提交于 12月 25, 2008

In each case, vpage is checked not to be NULL just after it is initialized
at the beginning of each loop iteration.

A simplified version of the semantic patch that makes this change is as
follows: (http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r exists@
local idexpression x;
expression E;
position p1,p2;
@@

if (x@p1 == NULL || ...) { ... when forall
   return ...; }
... when != \(x=E\|x--\|x++\|--x\|++x\|x-=E\|x+=E\|x|=E\|x&=E\|&x\)
(
x@p2 == NULL
|
x@p2 != NULL
)

// another path to the test that is not through p1?
@s exists@
local idexpression r.x;
position r.p1,r.p2;
@@

... when != x@p1
(
x@p2 == NULL
|
x@p2 != NULL
)

@fix depends on !s@
position r.p1,r.p2;
expression x,E;
statement S1,S2;
@@

(
- if ((x@p2 != NULL) || ...)
  S1
|
- if ((x@p2 == NULL) && ...) S1
|
- BUG_ON(x@p2 == NULL);
)
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

662f44af

drivers/net/au1000_eth.c: Remove redundant test · b0fd0d23

由 Julia Lawall 提交于 12月 25, 2008

phydev is checked to be not NULL a few lines above.

A simplified version of the semantic patch that makes this change is as
follows: (http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r exists@
local idexpression x;
expression E;
position p1,p2;
@@

if (x@p1 == NULL || ...) { ... when forall
   return ...; }
... when != \(x=E\|x--\|x++\|--x\|++x\|x-=E\|x+=E\|x|=E\|x&=E\|&x\)
(
x@p2 == NULL
|
x@p2 != NULL
)

// another path to the test that is not through p1?
@s exists@
local idexpression r.x;
position r.p1,r.p2;
@@

... when != x@p1
(
x@p2 == NULL
|
x@p2 != NULL
)

@fix depends on !s@
position r.p1,r.p2;
expression x,E;
statement S1,S2;
@@

(
- if ((x@p2 != NULL) || ...)
  S1
|
- if ((x@p2 == NULL) && ...) S1
|
- BUG_ON(x@p2 == NULL);
)
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

b0fd0d23

qlge: ql_adapter_down() typo · c062076c

由 Roel Kluin 提交于 12月 25, 2008

Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: NRon Mercer <ron.mercer@qlogic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

c062076c

netlink: fix (theoretical) overrun in message iteration · 619e803d

由 Vegard Nossum 提交于 12月 25, 2008

See commit 1045b03e ("netlink: fix
overrun in attribute iteration") for a detailed explanation of why
this patch is necessary.

In short, nlmsg_next() can make "remaining" go negative, and the
remaining >= sizeof(...) comparison will promote "remaining" to an
unsigned type, which means that the expression will evaluate to
true for negative numbers, even though it was not intended.

I put "theoretical" in the title because I have no evidence that
this can actually happen, but I suspect that a crafted netlink
packet can trigger some badness.

Note that the last test, which seemingly has the exact same
problem (also true for nla_ok()), is perfectly OK, since we
already know that remaining is positive.
Signed-off-by: NVegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

619e803d

tcp: Always set urgent pointer if it's beyond snd_nxt · 64ff3b93

由 Herbert Xu 提交于 12月 25, 2008

Our TCP stack does not set the urgent flag if the urgent pointer
does not fit in 16 bits, i.e., if it is more than 64K from the
sequence number of a packet.

This behaviour is different from the BSDs, and clearly contradicts
the purpose of urgent mode, which is to send the notification
(though not necessarily the associated data) as soon as possible.
Our current behaviour may in fact delay the urgent notification
indefinitely if the receiver window does not open up.

Simply matching BSD however may break legacy applications which
incorrectly rely on the out-of-band delivery of urgent data, and
conversely the in-band delivery of non-urgent data.

Alexey Kuznetsov suggested a safe solution of following BSD only
if the urgent pointer itself has not yet been transmitted.  This
way we guarantee that when the remote end sees the packet with
non-urgent data marked as urgent due to wrap-around we would have
advanced the urgent pointer beyond, either to the actual urgent
data or to an as-yet untransmitted packet.

The only potential downside is that applications on the remote
end may see multiple SIGURG notifications.  However, this would
occur anyway with other TCP stacks.  More importantly, the outcome
of such a duplicate notification is likely to be harmless since
the signal itself does not carry any information other than the
fact that we're in urgent mode.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

64ff3b93

sctp: Add validity check for SCTP_PARTIAL_DELIVERY_POINT socket option · 8510b937