linux.git/net/iucv, branch v6.6

net/iucv: Fix size of interrupt data

2023-03-17T00:34:40+00:00

iucv_irq_data needs to be 4 bytes larger.
These bytes are not used by the iucv module, but written by
the z/VM hypervisor in case a CPU is deconfigured.

Reported as:
BUG dma-kmalloc-64 (Not tainted): kmalloc Redzone overwritten
-----------------------------------------------------------------------------
0x0000000000400564-0x0000000000400567 @offset=1380. First byte 0x80 instead of 0xcc
Allocated in iucv_cpu_prepare+0x44/0xd0 age=167839 cpu=2 pid=1
__kmem_cache_alloc_node+0x166/0x450
kmalloc_node_trace+0x3a/0x70
iucv_cpu_prepare+0x44/0xd0
cpuhp_invoke_callback+0x156/0x2f0
cpuhp_issue_call+0xf0/0x298
__cpuhp_setup_state_cpuslocked+0x136/0x338
__cpuhp_setup_state+0xf4/0x288
iucv_init+0xf4/0x280
do_one_initcall+0x78/0x390
do_initcalls+0x11a/0x140
kernel_init_freeable+0x25e/0x2a0
kernel_init+0x2e/0x170
__ret_from_fork+0x3c/0x58
ret_from_fork+0xa/0x40
Freed in iucv_init+0x92/0x280 age=167839 cpu=2 pid=1
__kmem_cache_free+0x308/0x358
iucv_init+0x92/0x280
do_one_initcall+0x78/0x390
do_initcalls+0x11a/0x140
kernel_init_freeable+0x25e/0x2a0
kernel_init+0x2e/0x170
__ret_from_fork+0x3c/0x58
ret_from_fork+0xa/0x40
Slab 0x0000037200010000 objects=32 used=30 fp=0x0000000000400640 flags=0x1ffff00000010200(slab|head|node=0|zone=0|
Object 0x0000000000400540 @offset=1344 fp=0x0000000000000000
Redzone  0000000000400500: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc  ................
Redzone  0000000000400510: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc  ................
Redzone  0000000000400520: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc  ................
Redzone  0000000000400530: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc  ................
Object   0000000000400540: 00 01 00 03 00 00 00 00 00 00 00 00 00 00 00 00  ................
Object   0000000000400550: f3 86 81 f2 f4 82 f8 82 f0 f0 f0 f0 f0 f0 f0 f2  ................
Object   0000000000400560: 00 00 00 00 80 00 00 00 cc cc cc cc cc cc cc cc  ................
Object   0000000000400570: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc  ................
Redzone  0000000000400580: cc cc cc cc cc cc cc cc                          ........
Padding  00000000004005d4: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a  ZZZZZZZZZZZZZZZZ
Padding  00000000004005e4: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a  ZZZZZZZZZZZZZZZZ
Padding  00000000004005f4: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a              ZZZZZZZZZZZZ
CPU: 6 PID: 121030 Comm: 116-pai-crypto. Not tainted 6.3.0-20230221.rc0.git4.99b8246b2d71.300.fc37.s390x+debug #1
Hardware name: IBM 3931 A01 704 (z/VM 7.3.0)
Call Trace:
[<000000032aa034ec>] dump_stack_lvl+0xac/0x100
[<0000000329f5a6cc>] check_bytes_and_report+0x104/0x140
[<0000000329f5aa78>] check_object+0x370/0x3c0
[<0000000329f5ede6>] free_debug_processing+0x15e/0x348
[<0000000329f5f06a>] free_to_partial_list+0x9a/0x2f0
[<0000000329f5f4a4>] __slab_free+0x1e4/0x3a8
[<0000000329f61768>] __kmem_cache_free+0x308/0x358
[<000000032a91465c>] iucv_cpu_dead+0x6c/0x88
[<0000000329c2fc66>] cpuhp_invoke_callback+0x156/0x2f0
[<000000032aa062da>] _cpu_down.constprop.0+0x22a/0x5e0
[<0000000329c3243e>] cpu_device_down+0x4e/0x78
[<000000032a61dee0>] device_offline+0xc8/0x118
[<000000032a61e048>] online_store+0x60/0xe0
[<000000032a08b6b0>] kernfs_fop_write_iter+0x150/0x1e8
[<0000000329fab65c>] vfs_write+0x174/0x360
[<0000000329fab9fc>] ksys_write+0x74/0x100
[<000000032aa03a5a>] __do_syscall+0x1da/0x208
[<000000032aa177b2>] system_call+0x82/0xb0
INFO: lockdep is turned off.
FIX dma-kmalloc-64: Restoring kmalloc Redzone 0x0000000000400564-0x0000000000400567=0xcc
FIX dma-kmalloc-64: Object at 0x0000000000400540 not freed

Fixes: 2356f4cb1911 ("[S390]: Rewrite of the IUCV base code, part 2")
Signed-off-by: Alexandra Winter 
Link: https://lore.kernel.org/r/20230315131435.4113889-1-wintera@linux.ibm.com
Signed-off-by: Jakub Kicinski

net: keep sk->sk_forward_alloc as small as possible

2022-06-10T23:21:27+00:00

Currently, tcp_memory_allocated can hit tcp_mem[] limits quite fast.

Each TCP socket can forward allocate up to 2 MB of memory, even after
flow became less active.

10,000 sockets can have reserved 20 GB of memory,
and we have no shrinker in place to reclaim that.

Instead of trying to reclaim the extra allocations in some places,
just keep sk->sk_forward_alloc values as small as possible.

This should not impact performance too much now we have per-cpu
reserves: Changes to tcp_memory_allocated should not be too frequent.

For sockets not using SO_RESERVE_MEM:
 - idle sockets (no packets in tx/rx queues) have zero forward alloc.
 - non idle sockets have a forward alloc smaller than one page.

Note:

 - Removal of SK_RECLAIM_CHUNK and SK_RECLAIM_THRESHOLD
   is left to MPTCP maintainers as a follow up.

Signed-off-by: Eric Dumazet 
Reviewed-by: Shakeel Butt 
Acked-by: Soheil Hassas Yeganeh 
Signed-off-by: Jakub Kicinski

net: remove noblock parameter from skb_recv_datagram()

2022-04-06T12:45:26+00:00

skb_recv_datagram() has two parameters 'flags' and 'noblock' that are
merged inside skb_recv_datagram() by 'flags | (noblock ? MSG_DONTWAIT : 0)'

As 'flags' may contain MSG_DONTWAIT as value most callers split the 'flags'
into 'flags' and 'noblock' with finally obsolete bit operations like this:

skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &rc);

And this is not even done consistently with the 'flags' parameter.

This patch removes the obsolete and costly splitting into two parameters
and only performs bit operations when really needed on the caller side.

One missing conversion thankfully reported by kernel test robot. I missed
to enable kunit tests to build the mctp code.

Reported-by: kernel test robot 
Signed-off-by: Oliver Hartkopp 
Signed-off-by: David S. Miller

s390/iucv: sort out physical vs virtual pointers usage

2022-02-23T00:09:13+00:00

Fix virtual vs physical address confusion (which currently are the same).

Reviewed-by: Alexandra Winter 
Reviewed-by: Wenjia Zhang 
Signed-off-by: Alexander Gordeev 
Signed-off-by: Alexandra Winter 
Signed-off-by: Jakub Kicinski

net: Don't include filter.h from net/sock.h

2021-12-29T16:48:14+00:00

sock.h is pretty heavily used (5k objects rebuilt on x86 after
it's touched). We can drop the include of filter.h from it and
add a forward declaration of struct sk_filter instead.
This decreases the number of rebuilt objects when bpf.h
is touched from ~5k to ~1k.

There's a lot of missing includes this was masking. Primarily
in networking tho, this time.

Signed-off-by: Jakub Kicinski 
Signed-off-by: Alexei Starovoitov 
Acked-by: Marc Kleine-Budde 
Acked-by: Florian Fainelli 
Acked-by: Nikolay Aleksandrov 
Acked-by: Stefano Garzarella 
Link: https://lore.kernel.org/bpf/20211229004913.513372-1-kuba@kernel.org

net/af_iucv: Use struct_group() to zero struct iucv_sock region

2021-11-19T11:52:25+00:00

In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memset(), avoid intentionally writing across
neighboring fields.

Add struct_group() to mark the region of struct iucv_sock that gets
initialized to zero. Avoid the future warning:

In function 'fortify_memset_chk',
    inlined from 'iucv_sock_alloc' at net/iucv/af_iucv.c:476:2:
./include/linux/fortify-string.h:199:4: warning: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wattribute-warning]
  199 |    __write_overflow_field(p_size_field, size);
      |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Acked-by: Karsten Graul 
Link: https://lore.kernel.org/lkml/19ff61a0-0cda-6000-ce56-dc6b367c00d6@linux.ibm.com/
Signed-off-by: Kees Cook 
Signed-off-by: David S. Miller

net/af_iucv: fix kernel doc comments

2021-11-19T11:12:30+00:00

Fix kernel doc comments where appropriate, or remove incorrect kernel
doc indicators.

Acked-by: Julian Wiedmann 
Signed-off-by: Heiko Carstens 
Signed-off-by: Karsten Graul 
Signed-off-by: David S. Miller

net/iucv: fix kernel doc comments

2021-11-19T11:12:29+00:00

Fix kernel doc comments where appropriate or remove incorrect kernel
doc indicators.
Also move kernel doc comments directly before functions.

Signed-off-by: Heiko Carstens 
Signed-off-by: Karsten Graul 
Signed-off-by: David S. Miller

net/iucv: Replace deprecated CPU-hotplug functions.

2021-08-09T09:13:32+00:00

The functions get_online_cpus() and put_online_cpus() have been
deprecated during the CPU hotplug rework. They map directly to
cpus_read_lock() and cpus_read_unlock().

Replace deprecated CPU-hotplug functions with the official version.
The behavior remains unchanged.

Cc: Julian Wiedmann 
Cc: Karsten Graul 
Cc: "David S. Miller" 
Cc: Jakub Kicinski 
Cc: linux-s390@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior 
Signed-off-by: Julian Wiedmann 
Signed-off-by: Karsten Graul 
Signed-off-by: David S. Miller

net/iucv: get rid of register asm usage

2021-08-09T09:13:32+00:00

Using register asm statements has been proven to be very error prone,
especially when using code instrumentation where gcc may add function
calls, which clobbers register contents in an unexpected way.

Therefore get rid of register asm statements in iucv code, even though
there is currently nothing wrong with it. This way we know for sure
that the above mentioned bug class won't be introduced here.

Acked-by: Karsten Graul 
Signed-off-by: Heiko Carstens 
Signed-off-by: Karsten Graul 
Signed-off-by: David S. Miller