<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-dev/net/sctp, branch master</title>
<subtitle>Linux kernel development work - see feature branches</subtitle>
<id>https://git.zx2c4.com/linux-dev/atom/net/sctp?h=master</id>
<link rel='self' href='https://git.zx2c4.com/linux-dev/atom/net/sctp?h=master'/>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/'/>
<updated>2022-11-08T03:59:01Z</updated>
<entry>
<title>sctp: clear out_curr if all frag chunks of current msg are pruned</title>
<updated>2022-11-08T03:59:01Z</updated>
<author>
<name>Xin Long</name>
<email>lucien.xin@gmail.com</email>
</author>
<published>2022-11-04T21:45:16Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=2f201ae14ae0f91dbf1cffea7bb1e29e81d4d108'/>
<id>urn:sha1:2f201ae14ae0f91dbf1cffea7bb1e29e81d4d108</id>
<content type='text'>
A crash was reported by Zhen Chen:

  list_del corruption, ffffa035ddf01c18-&gt;next is NULL
  WARNING: CPU: 1 PID: 250682 at lib/list_debug.c:49 __list_del_entry_valid+0x59/0xe0
  RIP: 0010:__list_del_entry_valid+0x59/0xe0
  Call Trace:
   sctp_sched_dequeue_common+0x17/0x70 [sctp]
   sctp_sched_fcfs_dequeue+0x37/0x50 [sctp]
   sctp_outq_flush_data+0x85/0x360 [sctp]
   sctp_outq_uncork+0x77/0xa0 [sctp]
   sctp_cmd_interpreter.constprop.0+0x164/0x1450 [sctp]
   sctp_side_effects+0x37/0xe0 [sctp]
   sctp_do_sm+0xd0/0x230 [sctp]
   sctp_primitive_SEND+0x2f/0x40 [sctp]
   sctp_sendmsg_to_asoc+0x3fa/0x5c0 [sctp]
   sctp_sendmsg+0x3d5/0x440 [sctp]
   sock_sendmsg+0x5b/0x70

and in sctp_sched_fcfs_dequeue() it dequeued a chunk from stream
out_curr outq while this outq was empty.

Normally stream-&gt;out_curr must be set to NULL once all frag chunks of
current msg are dequeued, as we can see in sctp_sched_dequeue_done().
However, in sctp_prsctp_prune_unsent() as it is not a proper dequeue,
sctp_sched_dequeue_done() is not called to do this.

This patch is to fix it by simply setting out_curr to NULL when the
last frag chunk of current msg is dequeued from out_curr stream in
sctp_prsctp_prune_unsent().

Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations")
Reported-by: Zhen Chen &lt;chenzhen126@huawei.com&gt;
Tested-by: Caowangbao &lt;caowangbao@huawei.com&gt;
Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>sctp: remove the unnecessary sinfo_stream check in sctp_prsctp_prune_unsent</title>
<updated>2022-11-08T03:59:01Z</updated>
<author>
<name>Xin Long</name>
<email>lucien.xin@gmail.com</email>
</author>
<published>2022-11-04T21:45:15Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=9f0b773210c27a8f5d98ddb2fc4ba60a42a3285f'/>
<id>urn:sha1:9f0b773210c27a8f5d98ddb2fc4ba60a42a3285f</id>
<content type='text'>
Since commit 5bbbbe32a431 ("sctp: introduce stream scheduler foundations"),
sctp_stream_outq_migrate() has been called in sctp_stream_init/update to
removes those chunks to streams higher than the new max. There is no longer
need to do such check in sctp_prsctp_prune_unsent().

Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>treewide: use get_random_{u8,u16}() when possible, part 1</title>
<updated>2022-10-11T23:42:58Z</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2022-10-05T15:23:53Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=7e3cf0843fe505491baa05e355e83e6997e089dd'/>
<id>urn:sha1:7e3cf0843fe505491baa05e355e83e6997e089dd</id>
<content type='text'>
Rather than truncate a 32-bit value to a 16-bit value or an 8-bit value,
simply use the get_random_{u8,u16}() functions, which are faster than
wasting the additional bytes from a 32-bit value. This was done
mechanically with this coccinelle script:

@@
expression E;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u16;
typedef __be16;
typedef __le16;
typedef u8;
@@
(
- (get_random_u32() &amp; 0xffff)
+ get_random_u16()
|
- (get_random_u32() &amp; 0xff)
+ get_random_u8()
|
- (get_random_u32() % 65536)
+ get_random_u16()
|
- (get_random_u32() % 256)
+ get_random_u8()
|
- (get_random_u32() &gt;&gt; 16)
+ get_random_u16()
|
- (get_random_u32() &gt;&gt; 24)
+ get_random_u8()
|
- (u16)get_random_u32()
+ get_random_u16()
|
- (u8)get_random_u32()
+ get_random_u8()
|
- (__be16)get_random_u32()
+ (__be16)get_random_u16()
|
- (__le16)get_random_u32()
+ (__le16)get_random_u16()
|
- prandom_u32_max(65536)
+ get_random_u16()
|
- prandom_u32_max(256)
+ get_random_u8()
|
- E-&gt;inet_id = get_random_u32()
+ E-&gt;inet_id = get_random_u16()
)

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u16;
identifier v;
@@
- u16 v = get_random_u32();
+ u16 v = get_random_u16();

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u8;
identifier v;
@@
- u8 v = get_random_u32();
+ u8 v = get_random_u8();

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u16;
u16 v;
@@
-  v = get_random_u32();
+  v = get_random_u16();

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u8;
u8 v;
@@
-  v = get_random_u32();
+  v = get_random_u8();

// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@

        ((T)get_random_u32()@p &amp; (LITERAL))

// Examine limits
@script:python add_one@
literal &lt;&lt; literal_mask.LITERAL;
RESULT;
@@

value = None
if literal.startswith('0x'):
        value = int(literal, 16)
elif literal[0] in '123456789':
        value = int(literal, 10)
if value is None:
        print("I don't know how to handle %s" % (literal))
        cocci.include_match(False)
elif value &lt; 256:
        coccinelle.RESULT = cocci.make_ident("get_random_u8")
elif value &lt; 65536:
        coccinelle.RESULT = cocci.make_ident("get_random_u16")
else:
        print("Skipping large mask of %s" % (literal))
        cocci.include_match(False)

// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
identifier add_one.RESULT;
identifier FUNC;
@@

-       (FUNC()@p &amp; (LITERAL))
+       (RESULT() &amp; LITERAL)

Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Yury Norov &lt;yury.norov@gmail.com&gt;
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Toke Høiland-Jørgensen &lt;toke@toke.dk&gt; # for sch_cake
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</content>
</entry>
<entry>
<title>treewide: use prandom_u32_max() when possible, part 1</title>
<updated>2022-10-11T23:42:55Z</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2022-10-05T14:43:38Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=81895a65ec63ee1daec3255dc1a06675d2fbe915'/>
<id>urn:sha1:81895a65ec63ee1daec3255dc1a06675d2fbe915</id>
<content type='text'>
Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
the minimum required bytes from the RNG and avoids divisions. This was
done mechanically with this coccinelle script:

@basic@
expression E;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u64;
@@
(
- ((T)get_random_u32() % (E))
+ prandom_u32_max(E)
|
- ((T)get_random_u32() &amp; ((E) - 1))
+ prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2)
|
- ((u64)(E) * get_random_u32() &gt;&gt; 32)
+ prandom_u32_max(E)
|
- ((T)get_random_u32() &amp; ~PAGE_MASK)
+ prandom_u32_max(PAGE_SIZE)
)

@multi_line@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
identifier RAND;
expression E;
@@

-       RAND = get_random_u32();
        ... when != RAND
-       RAND %= (E);
+       RAND = prandom_u32_max(E);

// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@

        ((T)get_random_u32()@p &amp; (LITERAL))

// Add one to the literal.
@script:python add_one@
literal &lt;&lt; literal_mask.LITERAL;
RESULT;
@@

value = None
if literal.startswith('0x'):
        value = int(literal, 16)
elif literal[0] in '123456789':
        value = int(literal, 10)
if value is None:
        print("I don't know how to handle %s" % (literal))
        cocci.include_match(False)
elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1:
        print("Skipping 0x%x for cleanup elsewhere" % (value))
        cocci.include_match(False)
elif value &amp; (value + 1) != 0:
        print("Skipping 0x%x because it's not a power of two minus one" % (value))
        cocci.include_match(False)
elif literal.startswith('0x'):
        coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1))
else:
        coccinelle.RESULT = cocci.make_expr("%d" % (value + 1))

// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
expression add_one.RESULT;
identifier FUNC;
@@

-       (FUNC()@p &amp; (LITERAL))
+       prandom_u32_max(RESULT)

@collapse_ret@
type T;
identifier VAR;
expression E;
@@

 {
-       T VAR;
-       VAR = (E);
-       return VAR;
+       return E;
 }

@drop_var@
type T;
identifier VAR;
@@

 {
-       T VAR;
        ... when != VAR
 }

Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Yury Norov &lt;yury.norov@gmail.com&gt;
Reviewed-by: KP Singh &lt;kpsingh@kernel.org&gt;
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt; # for ext4 and sbitmap
Reviewed-by: Christoph Böhmwalder &lt;christoph.boehmwalder@linbit.com&gt; # for drbd
Acked-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt; # for s390
Acked-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt; # for mmc
Acked-by: Darrick J. Wong &lt;djwong@kernel.org&gt; # for xfs
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</content>
</entry>
<entry>
<title>sctp: handle the error returned from sctp_auth_asoc_init_active_key</title>
<updated>2022-09-30T11:36:40Z</updated>
<author>
<name>Xin Long</name>
<email>lucien.xin@gmail.com</email>
</author>
<published>2022-09-28T18:10:13Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=022152aaebe116a25c39818a07e175a8cd3c1e11'/>
<id>urn:sha1:022152aaebe116a25c39818a07e175a8cd3c1e11</id>
<content type='text'>
When it returns an error from sctp_auth_asoc_init_active_key(), the
active_key is actually not updated. The old sh_key will be freeed
while it's still used as active key in asoc. Then an use-after-free
will be triggered when sending patckets, as found by syzbot:

  sctp_auth_shkey_hold+0x22/0xa0 net/sctp/auth.c:112
  sctp_set_owner_w net/sctp/socket.c:132 [inline]
  sctp_sendmsg_to_asoc+0xbd5/0x1a20 net/sctp/socket.c:1863
  sctp_sendmsg+0x1053/0x1d50 net/sctp/socket.c:2025
  inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:819
  sock_sendmsg_nosec net/socket.c:714 [inline]
  sock_sendmsg+0xcf/0x120 net/socket.c:734

This patch is to fix it by not replacing the sh_key when it returns
errors from sctp_auth_asoc_init_active_key() in sctp_auth_set_key().
For sctp_auth_set_active_key(), old active_key_id will be set back
to asoc-&gt;active_key_id when the same thing happens.

Fixes: 58acd1009226 ("sctp: update active_key for asoc when old key is being replaced")
Reported-by: syzbot+a236dd8e9622ed8954a3@syzkaller.appspotmail.com
Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net</title>
<updated>2022-07-29T01:21:16Z</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2022-07-29T01:21:16Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=272ac32f566e3f925b20c231a2b30f6893aa258a'/>
<id>urn:sha1:272ac32f566e3f925b20c231a2b30f6893aa258a</id>
<content type='text'>
No conflicts.

Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>sctp: leave the err path free in sctp_stream_init to sctp_stream_free</title>
<updated>2022-07-28T01:23:22Z</updated>
<author>
<name>Xin Long</name>
<email>lucien.xin@gmail.com</email>
</author>
<published>2022-07-25T22:11:06Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=181d8d2066c000ba0a0e6940a7ad80f1a0e68e9d'/>
<id>urn:sha1:181d8d2066c000ba0a0e6940a7ad80f1a0e68e9d</id>
<content type='text'>
A NULL pointer dereference was reported by Wei Chen:

  BUG: kernel NULL pointer dereference, address: 0000000000000000
  RIP: 0010:__list_del_entry_valid+0x26/0x80
  Call Trace:
   &lt;TASK&gt;
   sctp_sched_dequeue_common+0x1c/0x90
   sctp_sched_prio_dequeue+0x67/0x80
   __sctp_outq_teardown+0x299/0x380
   sctp_outq_free+0x15/0x20
   sctp_association_free+0xc3/0x440
   sctp_do_sm+0x1ca7/0x2210
   sctp_assoc_bh_rcv+0x1f6/0x340

This happens when calling sctp_sendmsg without connecting to server first.
In this case, a data chunk already queues up in send queue of client side
when processing the INIT_ACK from server in sctp_process_init() where it
calls sctp_stream_init() to alloc stream_in. If it fails to alloc stream_in
all stream_out will be freed in sctp_stream_init's err path. Then in the
asoc freeing it will crash when dequeuing this data chunk as stream_out
is missing.

As we can't free stream out before dequeuing all data from send queue, and
this patch is to fix it by moving the err path stream_out/in freeing in
sctp_stream_init() to sctp_stream_free() which is eventually called when
freeing the asoc in sctp_association_free(). This fix also makes the code
in sctp_process_init() more clear.

Note that in sctp_association_init() when it fails in sctp_stream_init(),
sctp_association_free() will not be called, and in that case it should
go to 'stream_free' err path to free stream instead of 'fail_init'.

Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations")
Reported-by: Wei Chen &lt;harperchen1110@gmail.com&gt;
Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Link: https://lore.kernel.org/r/831a3dc100c4908ff76e5bcc363be97f2778bc0b.1658787066.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>sctp: fix sleep in atomic context bug in timer handlers</title>
<updated>2022-07-26T02:39:05Z</updated>
<author>
<name>Duoming Zhou</name>
<email>duoming@zju.edu.cn</email>
</author>
<published>2022-07-23T01:58:09Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=b89fc26f741d9f9efb51cba3e9b241cf1380ec5a'/>
<id>urn:sha1:b89fc26f741d9f9efb51cba3e9b241cf1380ec5a</id>
<content type='text'>
There are sleep in atomic context bugs in timer handlers of sctp
such as sctp_generate_t3_rtx_event(), sctp_generate_probe_event(),
sctp_generate_t1_init_event(), sctp_generate_timeout_event(),
sctp_generate_t3_rtx_event() and so on.

The root cause is sctp_sched_prio_init_sid() with GFP_KERNEL parameter
that may sleep could be called by different timer handlers which is in
interrupt context.

One of the call paths that could trigger bug is shown below:

      (interrupt context)
sctp_generate_probe_event
  sctp_do_sm
    sctp_side_effects
      sctp_cmd_interpreter
        sctp_outq_teardown
          sctp_outq_init
            sctp_sched_set_sched
              n-&gt;init_sid(..,GFP_KERNEL)
                sctp_sched_prio_init_sid //may sleep

This patch changes gfp_t parameter of init_sid in sctp_sched_set_sched()
from GFP_KERNEL to GFP_ATOMIC in order to prevent sleep in atomic
context bugs.

Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations")
Signed-off-by: Duoming Zhou &lt;duoming@zju.edu.cn&gt;
Acked-by: Marcelo Ricardo Leitner &lt;marcelo.leitner@gmail.com&gt;
Link: https://lore.kernel.org/r/20220723015809.11553-1-duoming@zju.edu.cn
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net</title>
<updated>2022-07-21T20:03:39Z</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2022-07-21T20:03:39Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=6e0e846ee2ab01bc44254e6a0a6a6a0db1cba16d'/>
<id>urn:sha1:6e0e846ee2ab01bc44254e6a0a6a6a0db1cba16d</id>
<content type='text'>
No conflicts.

Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>ip: Fix data-races around sysctl_ip_nonlocal_bind.</title>
<updated>2022-07-15T10:49:55Z</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-07-13T20:51:55Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=289d3b21fb0bfc94c4e98f10635bba1824e5f83c'/>
<id>urn:sha1:289d3b21fb0bfc94c4e98f10635bba1824e5f83c</id>
<content type='text'>
While reading sysctl_ip_nonlocal_bind, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
</feed>
