Skip to content
  1. Nov 16, 2023
  3. Nov 15, 2023
  5. Nov 14, 2023
    • Eric Dumazet's avatar
      af_unix: fix use-after-free in unix_stream_read_actor() · 4b7b4926
      Eric Dumazet authored 
      

syzbot reported the following crash [1]

After releasing unix socket lock, u->oob_skb can be changed
by another thread. We must temporarily increase skb refcount
to make sure this other thread will not free the skb under us.

[1]

BUG: KASAN: slab-use-after-free in unix_stream_read_actor+0xa7/0xc0 net/unix/af_unix.c:2866
Read of size 4 at addr ffff88801f3b9cc4 by task syz-executor107/5297

CPU: 1 PID: 5297 Comm: syz-executor107 Not tainted 6.6.0-syzkaller-15910-gb8e3a87a627b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:364 [inline]
print_report+0xc4/0x620 mm/kasan/report.c:475
kasan_report+0xda/0x110 mm/kasan/report.c:588
unix_stream_read_actor+0xa7/0xc0 net/unix/af_unix.c:2866
unix_stream_recv_urg net/unix/af_unix.c:2587 [inline]
unix_stream_read_generic+0x19a5/0x2480 net/unix/af_unix.c:2666
unix_stream_recvmsg+0x189/0x1b0 net/unix/af_unix.c:2903
sock_recvmsg_nosec net/socket.c:1044 [inline]
sock_recvmsg+0xe2/0x170 net/socket.c:1066
____sys_recvmsg+0x21f/0x5c0 net/socket.c:2803
___sys_recvmsg+0x115/0x1a0 net/socket.c:2845
__sys_recvmsg+0x114/0x1e0 net/socket.c:2875
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7fc67492c559
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc6748ab228 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 000000000000001c RCX: 00007fc67492c559
RDX: 0000000040010083 RSI: 0000000020000140 RDI: 0000000000000004
RBP: 00007fc6749b6348 R08: 00007fc6748ab6c0 R09: 00007fc6748ab6c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc6749b6340
R13: 00007fc6749b634c R14: 00007ffe9fac52a0 R15: 00007ffe9fac5388
</TASK>

Allocated by task 5295:
kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
kasan_set_track+0x25/0x30 mm/kasan/common.c:52
__kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:328
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook mm/slab.h:763 [inline]
slab_alloc_node mm/slub.c:3478 [inline]
kmem_cache_alloc_node+0x180/0x3c0 mm/slub.c:3523
__alloc_skb+0x287/0x330 net/core/skbuff.c:641
alloc_skb include/linux/skbuff.h:1286 [inline]
alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6331
sock_alloc_send_pskb+0x7e4/0x970 net/core/sock.c:2780
sock_alloc_send_skb include/net/sock.h:1884 [inline]
queue_oob net/unix/af_unix.c:2147 [inline]
unix_stream_sendmsg+0xb5f/0x10a0 net/unix/af_unix.c:2301
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0xd5/0x180 net/socket.c:745
____sys_sendmsg+0x6ac/0x940 net/socket.c:2584
___sys_sendmsg+0x135/0x1d0 net/socket.c:2638
__sys_sendmsg+0x117/0x1e0 net/socket.c:2667
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

Freed by task 5295:
kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
kasan_set_track+0x25/0x30 mm/kasan/common.c:52
kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:522
____kasan_slab_free mm/kasan/common.c:236 [inline]
____kasan_slab_free+0x15b/0x1b0 mm/kasan/common.c:200
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1800 [inline]
slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826
slab_free mm/slub.c:3809 [inline]
kmem_cache_free+0xf8/0x340 mm/slub.c:3831
kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:1015
__kfree_skb net/core/skbuff.c:1073 [inline]
consume_skb net/core/skbuff.c:1288 [inline]
consume_skb+0xdf/0x170 net/core/skbuff.c:1282
queue_oob net/unix/af_unix.c:2178 [inline]
unix_stream_sendmsg+0xd49/0x10a0 net/unix/af_unix.c:2301
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0xd5/0x180 net/socket.c:745
____sys_sendmsg+0x6ac/0x940 net/socket.c:2584
___sys_sendmsg+0x135/0x1d0 net/socket.c:2638
__sys_sendmsg+0x117/0x1e0 net/socket.c:2667
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

The buggy address belongs to the object at ffff88801f3b9c80
which belongs to the cache skbuff_head_cache of size 240
The buggy address is located 68 bytes inside of
freed 240-byte region [ffff88801f3b9c80, ffff88801f3b9d70)

The buggy address belongs to the physical page:
page:ffffea00007cee40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1f3b9
flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000800 ffff888142a60640 dead000000000122 0000000000000000
raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 5299, tgid 5283 (syz-executor107), ts 103803840339, free_ts 103600093431
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1537
prep_new_page mm/page_alloc.c:1544 [inline]
get_page_from_freelist+0xa25/0x36c0 mm/page_alloc.c:3312
__alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4568
alloc_pages_mpol+0x258/0x5f0 mm/mempolicy.c:2133
alloc_slab_page mm/slub.c:1870 [inline]
allocate_slab+0x251/0x380 mm/slub.c:2017
new_slab mm/slub.c:2070 [inline]
___slab_alloc+0x8c7/0x1580 mm/slub.c:3223
__slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322
__slab_alloc_node mm/slub.c:3375 [inline]
slab_alloc_node mm/slub.c:3468 [inline]
kmem_cache_alloc_node+0x132/0x3c0 mm/slub.c:3523
__alloc_skb+0x287/0x330 net/core/skbuff.c:641
alloc_skb include/linux/skbuff.h:1286 [inline]
alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6331
sock_alloc_send_pskb+0x7e4/0x970 net/core/sock.c:2780
sock_alloc_send_skb include/net/sock.h:1884 [inline]
queue_oob net/unix/af_unix.c:2147 [inline]
unix_stream_sendmsg+0xb5f/0x10a0 net/unix/af_unix.c:2301
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0xd5/0x180 net/socket.c:745
____sys_sendmsg+0x6ac/0x940 net/socket.c:2584
___sys_sendmsg+0x135/0x1d0 net/socket.c:2638
__sys_sendmsg+0x117/0x1e0 net/socket.c:2667
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1137 [inline]
free_unref_page_prepare+0x4f8/0xa90 mm/page_alloc.c:2347
free_unref_page+0x33/0x3b0 mm/page_alloc.c:2487
__unfreeze_partials+0x21d/0x240 mm/slub.c:2655
qlink_free mm/kasan/quarantine.c:168 [inline]
qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187
kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:294
__kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:305
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook mm/slab.h:763 [inline]
slab_alloc_node mm/slub.c:3478 [inline]
slab_alloc mm/slub.c:3486 [inline]
__kmem_cache_alloc_lru mm/slub.c:3493 [inline]
kmem_cache_alloc+0x15d/0x380 mm/slub.c:3502
vm_area_dup+0x21/0x2f0 kernel/fork.c:500
__split_vma+0x17d/0x1070 mm/mmap.c:2365
split_vma mm/mmap.c:2437 [inline]
vma_modify+0x25d/0x450 mm/mmap.c:2472
vma_modify_flags include/linux/mm.h:3271 [inline]
mprotect_fixup+0x228/0xc80 mm/mprotect.c:635
do_mprotect_pkey+0x852/0xd60 mm/mprotect.c:809
__do_sys_mprotect mm/mprotect.c:830 [inline]
__se_sys_mprotect mm/mprotect.c:827 [inline]
__x64_sys_mprotect+0x78/0xb0 mm/mprotect.c:827
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

Memory state around the buggy address:
ffff88801f3b9b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88801f3b9c00: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
>ffff88801f3b9c80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88801f3b9d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
ffff88801f3b9d80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb

Fixes: 876c14ad ("af_unix: fix holding spinlock in oob handling")
Reported-and-tested-by: default avatar <syzbot+7a2d546fa43e49315ed3@syzkaller.appspotmail.com>
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Cc: Rao Shoaib <rao.shoaib@oracle.com>
Reviewed-by: default avatarRao shoaib <rao.shoaib@oracle.com>
Link: https://lore.kernel.org/r/20231113134938.168151-1-edumazet@google.com


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
      4b7b4926
    • Jakub Kicinski's avatar
      Merge branch 'r8169-fix-dash-devices-network-lost-issue' · 48c205c6
      Jakub Kicinski authored 
      ChunHao Lin says:

====================
r8169: fix DASH devices network lost issue

This series are used to fix network lost issue on systems that support
DASH. It has been tested on rtl8168ep and rtl8168fp.
====================

Link: https://lore.kernel.org/r/20231109173400.4573-1-hau@realtek.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      48c205c6
    • ChunHao Lin's avatar
      r8169: fix network lost after resume on DASH systems · 868c3b95
      ChunHao Lin authored 
      

Device that support DASH may be reseted or powered off during suspend.
So driver needs to handle DASH during system suspend and resume. Or
DASH firmware will influence device behavior and causes network lost.

Fixes: b646d900 ("r8169: magic.")
Cc: stable@vger.kernel.org
Reviewed-by: default avatarHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: default avatarChunHao Lin <hau@realtek.com>
Link: https://lore.kernel.org/r/20231109173400.4573-3-hau@realtek.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      868c3b95
    • ChunHao Lin's avatar
      r8169: add handling DASH when DASH is disabled · 0ab0c45d
      ChunHao Lin authored 
      

For devices that support DASH, even DASH is disabled, there may still
exist a default firmware that will influence device behavior.
So driver needs to handle DASH for devices that support DASH, no
matter the DASH status is.

This patch also prepares for "fix network lost after resume on DASH
systems".

Fixes: ee7a1beb ("r8169:call "rtl8168_driver_start" "rtl8168_driver_stop" only when hardware dash function is enabled")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarChunHao Lin <hau@realtek.com>
Reviewed-by: default avatarHeiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/20231109173400.4573-2-hau@realtek.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      0ab0c45d
    • Jakub Kicinski's avatar
      Merge branch 'fix-large-frames-in-the-gemini-ethernet-driver' · 334e90b8
      Jakub Kicinski authored 
      Linus Walleij says:

====================
Fix large frames in the Gemini ethernet driver

This is the result of a bug hunt for a problem with the
RTL8366RB DSA switch leading me wrong all over the place.

I am indebted to Vladimir Oltean who as usual pointed
out where the real problem was, many thanks!

Tryig to actually use big ("jumbo") frames on this
hardware uncovered the real bugs. Then I tested it on
the DSA switch and it indeed fixes the issue.

To make sure it also works fine with big frames on
non-DSA devices I also copied a large video file over
scp to a device with maximum frame size, the data
was transported in large TCP packets ending up in
0x7ff sized frames using software checksumming at
~2.0 MB/s.

If I set down the MTU to the standard 1500 bytes so
that hardware checksumming is used, the scp transfer
of the same file was slightly lower, ~1.8-1.9 MB/s.

Despite this not being the best test it shows that
we can now stress the hardware with large frames
and that software checksum works fine.

v3: https://lore.kernel.org/r/20231107-gemini-largeframe-fix-v3-0-e3803c080b75@linaro.org
v2: https://lore.kernel.org/r/20231105-gemini-largeframe-fix-v2-0-cd3a5aa6c496@linaro.org
v1: https://lore.kernel.org/r/20231104-gemini-largeframe-fix-v1-0-9c5513f22f33@linaro.org
====================

Link: https://lore.kernel.org/r/20231109-gemini-largeframe-fix-v4-0-6e611528db08@linaro.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      334e90b8
    • Linus Walleij's avatar
      net: ethernet: cortina: Fix MTU max setting · dc6c0bfb
      Linus Walleij authored 
      

The RX max frame size is over 10000 for the Gemini ethernet,
but the TX max frame size is actually just 2047 (0x7ff after
checking the datasheet). Reflect this in what we offer to Linux,
cap the MTU at the TX max frame minus ethernet headers.

We delete the code disabling the hardware checksum for large
MTUs as netdev->mtu can no longer be larger than
netdev->max_mtu meaning the if()-clause in gmac_fix_features()
is never true.

Fixes: 4d5ae32f ("net: ethernet: Add a driver for Gemini gigabit ethernet")
Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: default avatarVladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20231109-gemini-largeframe-fix-v4-3-6e611528db08@linaro.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      dc6c0bfb
    • Linus Walleij's avatar
      net: ethernet: cortina: Handle large frames · d4d0c5b4
      Linus Walleij authored 
      

The Gemini ethernet controller provides hardware checksumming
for frames up to 1514 bytes including ethernet headers but not
FCS.

If we start sending bigger frames (after first bumping up the MTU
on both interfaces sending and receiving the frames), truncated
packets start to appear on the target such as in this tcpdump
resulting from ping -s 1474:

23:34:17.241983 14:d6:4d:a8:3c:4f (oui Unknown) > bc:ae:c5:6b:a8:3d (oui Unknown),
ethertype IPv4 (0x0800), length 1514: truncated-ip - 2 bytes missing!
(tos 0x0, ttl 64, id 32653, offset 0, flags [DF], proto ICMP (1), length 1502)
OpenWrt.lan > Fecusia: ICMP echo request, id 1672, seq 50, length 1482

If we bypass the hardware checksumming and provide a software
fallback, everything starts working fine up to the max TX MTU
of 2047 bytes, for example ping -s2000 192.168.1.2:

00:44:29.587598 bc:ae:c5:6b:a8:3d (oui Unknown) > 14:d6:4d:a8:3c:4f (oui Unknown),
ethertype IPv4 (0x0800), length 2042:
(tos 0x0, ttl 64, id 51828, offset 0, flags [none], proto ICMP (1), length 2028)
Fecusia > OpenWrt.lan: ICMP echo reply, id 1683, seq 4, length 2008

The bit enabling to bypass hardware checksum (or any of the
"TSS" bits) are undocumented in the hardware reference manual.
The entire hardware checksum unit appears undocumented. The
conclusion that we need to use the "bypass" bit was found by
trial-and-error.

Since no hardware checksum will happen, we slot in a software
checksum fallback.

Check for the condition where we need to compute checksum on the
skb with either hardware or software using == CHECKSUM_PARTIAL instead
of != CHECKSUM_NONE which is an incomplete check according to
<linux/skbuff.h>.

On the D-Link DIR-685 router this fixes a bug on the conduit
interface to the RTL8366RB DSA switch: as the switch needs to add
space for its tag it increases the MTU on the conduit interface
to 1504 and that means that when the router sends packages
of 1500 bytes these get an extra 4 bytes of DSA tag and the
transfer fails because of the erroneous hardware checksumming,
affecting such basic functionality as the LuCI web interface.

Fixes: 4d5ae32f ("net: ethernet: Add a driver for Gemini gigabit ethernet")
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: default avatarVladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20231109-gemini-largeframe-fix-v4-2-6e611528db08@linaro.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      d4d0c5b4
    • Linus Walleij's avatar
      net: ethernet: cortina: Fix max RX frame define · 510e35fb
      Linus Walleij authored 
      

Enumerator 3 is 1548 bytes according to the datasheet.
Not 1542.

Fixes: 4d5ae32f ("net: ethernet: Add a driver for Gemini gigabit ethernet")
Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: default avatarVladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20231109-gemini-largeframe-fix-v4-1-6e611528db08@linaro.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      510e35fb
    • Eric Dumazet's avatar
      bonding: stop the device in bond_setup_by_slave() · 3cffa2dd
      Eric Dumazet authored 
      

Commit 9eed321c ("net: lapbether: only support ethernet devices")
has been able to keep syzbot away from net/lapb, until today.

In the following splat [1], the issue is that a lapbether device has
been created on a bonding device without members. Then adding a non
ARPHRD_ETHER member forced the bonding master to change its type.

The fix is to make sure we call dev_close() in bond_setup_by_slave()
so that the potential linked lapbether devices (or any other devices
having assumptions on the physical device) are removed.

A similar bug has been addressed in commit 40baec22
("bonding: fix panic on non-ARPHRD_ETHER enslave failure")

[1]
skbuff: skb_under_panic: text:ffff800089508810 len:44 put:40 head:ffff0000c78e7c00 data:ffff0000c78e7bea tail:0x16 end:0x140 dev:bond0
kernel BUG at net/core/skbuff.c:192 !
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 6007 Comm: syz-executor383 Not tainted 6.6.0-rc3-syzkaller-gbf6547d8715b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : skb_panic net/core/skbuff.c:188 [inline]
pc : skb_under_panic+0x13c/0x140 net/core/skbuff.c:202
lr : skb_panic net/core/skbuff.c:188 [inline]
lr : skb_under_panic+0x13c/0x140 net/core/skbuff.c:202
sp : ffff800096a06aa0
x29: ffff800096a06ab0 x28: ffff800096a06ba0 x27: dfff800000000000
x26: ffff0000ce9b9b50 x25: 0000000000000016 x24: ffff0000c78e7bea
x23: ffff0000c78e7c00 x22: 000000000000002c x21: 0000000000000140
x20: 0000000000000028 x19: ffff800089508810 x18: ffff800096a06100
x17: 0000000000000000 x16: ffff80008a629a3c x15: 0000000000000001
x14: 1fffe00036837a32 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000201 x10: 0000000000000000 x9 : cb50b496c519aa00
x8 : cb50b496c519aa00 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff800096a063b8 x4 : ffff80008e280f80 x3 : ffff8000805ad11c
x2 : 0000000000000001 x1 : 0000000100000201 x0 : 0000000000000086
Call trace:
skb_panic net/core/skbuff.c:188 [inline]
skb_under_panic+0x13c/0x140 net/core/skbuff.c:202
skb_push+0xf0/0x108 net/core/skbuff.c:2446
ip6gre_header+0xbc/0x738 net/ipv6/ip6_gre.c:1384
dev_hard_header include/linux/netdevice.h:3136 [inline]
lapbeth_data_transmit+0x1c4/0x298 drivers/net/wan/lapbether.c:257
lapb_data_transmit+0x8c/0xb0 net/lapb/lapb_iface.c:447
lapb_transmit_buffer+0x178/0x204 net/lapb/lapb_out.c:149
lapb_send_control+0x220/0x320 net/lapb/lapb_subr.c:251
__lapb_disconnect_request+0x9c/0x17c net/lapb/lapb_iface.c:326
lapb_device_event+0x288/0x4e0 net/lapb/lapb_iface.c:492
notifier_call_chain+0x1a4/0x510 kernel/notifier.c:93
raw_notifier_call_chain+0x3c/0x50 kernel/notifier.c:461
call_netdevice_notifiers_info net/core/dev.c:1970 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2008 [inline]
call_netdevice_notifiers net/core/dev.c:2022 [inline]
__dev_close_many+0x1b8/0x3c4 net/core/dev.c:1508
dev_close_many+0x1e0/0x470 net/core/dev.c:1559
dev_close+0x174/0x250 net/core/dev.c:1585
lapbeth_device_event+0x2e4/0x958 drivers/net/wan/lapbether.c:466
notifier_call_chain+0x1a4/0x510 kernel/notifier.c:93
raw_notifier_call_chain+0x3c/0x50 kernel/notifier.c:461
call_netdevice_notifiers_info net/core/dev.c:1970 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2008 [inline]
call_netdevice_notifiers net/core/dev.c:2022 [inline]
__dev_close_many+0x1b8/0x3c4 net/core/dev.c:1508
dev_close_many+0x1e0/0x470 net/core/dev.c:1559
dev_close+0x174/0x250 net/core/dev.c:1585
bond_enslave+0x2298/0x30cc drivers/net/bonding/bond_main.c:2332
bond_do_ioctl+0x268/0xc64 drivers/net/bonding/bond_main.c:4539
dev_ifsioc+0x754/0x9ac
dev_ioctl+0x4d8/0xd34 net/core/dev_ioctl.c:786
sock_do_ioctl+0x1d4/0x2d0 net/socket.c:1217
sock_ioctl+0x4e8/0x834 net/socket.c:1322
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl fs/ioctl.c:857 [inline]
__arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:857
__invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155
el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678
el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696
el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591
Code: aa1803e6 aa1903e7 a90023f5 94785b8b (d4210000)

Fixes: 872254dd ("net/bonding: Enable bonding to enslave non ARPHRD_ETHER")
Reported-by: default avatarsyzbot <syzkaller@googlegroups.com>
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Acked-by: default avatarJay Vosburgh <jay.vosburgh@canonical.com>
Reviewed-by: default avatarHangbin Liu <liuhangbin@gmail.com>
Link: https://lore.kernel.org/r/20231109180102.4085183-1-edumazet@google.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      3cffa2dd
    • Eric Dumazet's avatar
      ptp: annotate data-race around q->head and q->tail · 73bde5a3
      Eric Dumazet authored 
      

As I was working on a syzbot report, I found that KCSAN would
probably complain that reading q->head or q->tail without
barriers could lead to invalid results.

Add corresponding READ_ONCE() and WRITE_ONCE() to avoid
load-store tearing.

Fixes: d94ba80e ("ptp: Added a brand new class driver for ptp clocks.")
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Acked-by: default avatarRichard Cochran <richardcochran@gmail.com>
Link: https://lore.kernel.org/r/20231109174859.3995880-1-edumazet@google.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      73bde5a3
    • Jakub Kicinski's avatar
      Revert "ptp: Fixes a null pointer dereference in ptp_ioctl" · 4b3812d9
      Jakub Kicinski authored 
      This reverts commit 8a4f030d.

Richard says:

  The test itself is harmless, but keeping it will make people think,
  "oh this pointer can be invalid."

  In fact the core stack ensures that ioctl() can't be invoked after
  release(), otherwise Bad Stuff happens.

Fixes: 8a4f030d ("ptp: Fixes a null pointer dereference in ptp_ioctl")
Link: https://lore.kernel.org/all/ZVAf_qdRfDAQYUt-@hoboy.vegasvil.org/


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      4b3812d9
    • Dan Nowlin's avatar
      ice: fix DDP package download for packages without signature segment · a778616e
      Dan Nowlin authored 
      

Commit 3cbdb034 ("ice: Add support for E830 DDP package segment")
incorrectly removed support for package download for packages without a
signature segment. These packages include the signature buffer inline
in the configurations buffers, and not in a signature segment.

Fix package download by providing download support for both packages
with (ice_download_pkg_with_sig_seg()) and without signature segment
(ice_download_pkg_without_sig_seg()).

Fixes: 3cbdb034 ("ice: Add support for E830 DDP package segment")
Reported-by: default avatarMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Closes: https://lore.kernel.org/netdev/ZUT50a94kk2pMGKb@boxer/


Tested-by: default avatarMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Reviewed-by: default avatarWojciech Drewek <wojciech.drewek@intel.com>
Reviewed-by: default avatarJacob Keller <jacob.e.keller@intel.com>
Signed-off-by: default avatarDan Nowlin <dan.nowlin@intel.com>
Signed-off-by: default avatarPaul Greenwalt <paul.greenwalt@intel.com>
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Tested-by: Arpana Arland <arpanax.arland@intel.com> (A Contingent worker at Intel)
Signed-off-by: default avatarTony Nguyen <anthony.l.nguyen@intel.com>
      a778616e
    • Arkadiusz Kubalewski's avatar
      ice: dpll: fix output pin capabilities · 6db5f2cd
      Arkadiusz Kubalewski authored 
      

The dpll output pins which are used to feed clock signal of PHY and MAC
circuits cannot be disconnected, those integrated circuits require clock
signal for operation.
By stopping assignment of DPLL_PIN_CAPABILITIES_STATE_CAN_CHANGE pin
capability, prevent the user from invoking the state set callback on
those pins, setting the state on those pins already returns error, as
firmware doesn't allow the change of their state.

Fixes: d7999f5e ("ice: implement dpll interface to control cgu")
Fixes: 8a3a565f ("ice: add admin commands to access cgu configuration")
Reviewed-by: default avatarAndrii Staikov <andrii.staikov@intel.com>
Signed-off-by: default avatarArkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Tested-by: Sunitha Mekala <sunithax.d.mekala@intel.com> (A Contingent worker at Intel)
Signed-off-by: default avatarTony Nguyen <anthony.l.nguyen@intel.com>
      6db5f2cd
    • Arkadiusz Kubalewski's avatar
      ice: dpll: fix check for dpll input priority range · 4a4027f2
      Arkadiusz Kubalewski authored 
      

Supported priority value for input pins may differ with regard of NIC
firmware version. E810T NICs with 3.20/4.00 FW versions would accept
priority range 0-31, where firmware 4.10+ would support the range 0-9
and extra value of 255.
Remove the in-range check as the driver has no information on supported
values from the running firmware, let firmware decide if given value is
correct and return extack error if the value is not supported.

Fixes: d7999f5e ("ice: implement dpll interface to control cgu")
Reviewed-by: default avatarPrzemek Kitszel <przemyslaw.kitszel@intel.com>
Reviewed-by: default avatarJacob Keller <jacob.e.keller@intel.com>
Signed-off-by: default avatarArkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Tested-by: Sunitha Mekala <sunithax.d.mekala@intel.com> (A Contingent worker at Intel)
Signed-off-by: default avatarTony Nguyen <anthony.l.nguyen@intel.com>
      4a4027f2
    • Arkadiusz Kubalewski's avatar
      ice: dpll: fix initial lock status of dpll · 7a1aba89
      Arkadiusz Kubalewski authored 
      

When dpll device is registered and dpll subsystem performs notify of a
new device, the lock state value provided to dpll subsystem equals 0
which is invalid value for the `enum dpll_lock_status`.
Provide correct value by obtaining it from firmware before registering
the dpll device.

Fixes: d7999f5e ("ice: implement dpll interface to control cgu")
Signed-off-by: default avatarAleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: default avatarArkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Tested-by: Sunitha Mekala <sunithax.d.mekala@intel.com> (A Contingent worker at Intel)
Signed-off-by: default avatarTony Nguyen <anthony.l.nguyen@intel.com>
      7a1aba89
  7. Nov 13, 2023
    • Willem de Bruijn's avatar
      ppp: limit MRU to 64K · c0a2a1b0
      Willem de Bruijn authored 
      

ppp_sync_ioctl allows setting device MRU, but does not sanity check
this input.

Limit to a sane upper bound of 64KB.

No implementation I could find generates larger than 64KB frames.
RFC 2823 mentions an upper bound of PPP over SDL of 64KB based on the
16-bit length field. Other protocols will be smaller, such as PPPoE
(9KB jumbo frame) and PPPoA (18190 maximum CPCS-SDU size, RFC 2364).
PPTP and L2TP encapsulate in IP.

Syzbot managed to trigger alloc warning in __alloc_pages:

	if (WARN_ON_ONCE_GFP(order > MAX_ORDER, gfp))

    WARNING: CPU: 1 PID: 37 at mm/page_alloc.c:4544 __alloc_pages+0x3ab/0x4a0 mm/page_alloc.c:4544

    __alloc_skb+0x12b/0x330 net/core/skbuff.c:651
    __netdev_alloc_skb+0x72/0x3f0 net/core/skbuff.c:715
    netdev_alloc_skb include/linux/skbuff.h:3225 [inline]
    dev_alloc_skb include/linux/skbuff.h:3238 [inline]
    ppp_sync_input drivers/net/ppp/ppp_synctty.c:669 [inline]
    ppp_sync_receive+0xff/0x680 drivers/net/ppp/ppp_synctty.c:334
    tty_ldisc_receive_buf+0x14c/0x180 drivers/tty/tty_buffer.c:390
    tty_port_default_receive_buf+0x70/0xb0 drivers/tty/tty_port.c:37
    receive_buf drivers/tty/tty_buffer.c:444 [inline]
    flush_to_ldisc+0x261/0x780 drivers/tty/tty_buffer.c:494
    process_one_work+0x884/0x15c0 kernel/workqueue.c:2630

With call

    ioctl$PPPIOCSMRU1(r1, 0x40047452, &(0x7f0000000100)=0x5e6417a8)

Similar code exists in other drivers that implement ppp_channel_ops
ioctl PPPIOCSMRU. Those might also be in scope. Notably excluded from
this are pppol2tp_ioctl and pppoe_ioctl.

This code goes back to the start of git history.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Reported-by: default avatar <syzbot+6177e1f90d92583bcc58@syzkaller.appspotmail.com>
Signed-off-by: default avatarWillem de Bruijn <willemb@google.com>
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      c0a2a1b0
    • Sven Auhagen's avatar
      net: mvneta: fix calls to page_pool_get_stats · ca8add92
      Sven Auhagen authored 
      

Calling page_pool_get_stats in the mvneta driver without checks
leads to kernel crashes.
First the page pool is only available if the bm is not used.
The page pool is also not allocated when the port is stopped.
It can also be not allocated in case of errors.

The current implementation leads to the following crash calling
ethstats on a port that is down or when calling it at the wrong moment:

ble to handle kernel NULL pointer dereference at virtual address 00000070
[00000070] *pgd=00000000
Internal error: Oops: 5 [#1] SMP ARM
Hardware name: Marvell Armada 380/385 (Device Tree)
PC is at page_pool_get_stats+0x18/0x1cc
LR is at mvneta_ethtool_get_stats+0xa0/0xe0 [mvneta]
pc : [<c0b413cc>]    lr : [<bf0a98d8>]    psr: a0000013
sp : f1439d48  ip : f1439dc0  fp : 0000001d
r10: 00000100  r9 : c4816b80  r8 : f0d75150
r7 : bf0b400c  r6 : c238f000  r5 : 00000000  r4 : f1439d68
r3 : c2091040  r2 : ffffffd8  r1 : f1439d68  r0 : 00000000
Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 10c5387d  Table: 066b004a  DAC: 00000051
Register r0 information: NULL pointer
Register r1 information: 2-page vmalloc region starting at 0xf1438000 allocated at kernel_clone+0x9c/0x390
Register r2 information: non-paged memory
Register r3 information: slab kmalloc-2k start c2091000 pointer offset 64 size 2048
Register r4 information: 2-page vmalloc region starting at 0xf1438000 allocated at kernel_clone+0x9c/0x390
Register r5 information: NULL pointer
Register r6 information: slab kmalloc-cg-4k start c238f000 pointer offset 0 size 4096
Register r7 information: 15-page vmalloc region starting at 0xbf0a8000 allocated at load_module+0xa30/0x219c
Register r8 information: 1-page vmalloc region starting at 0xf0d75000 allocated at ethtool_get_stats+0x138/0x208
Register r9 information: slab task_struct start c4816b80 pointer offset 0
Register r10 information: non-paged memory
Register r11 information: non-paged memory
Register r12 information: 2-page vmalloc region starting at 0xf1438000 allocated at kernel_clone+0x9c/0x390
Process snmpd (pid: 733, stack limit = 0x38de3a88)
Stack: (0xf1439d48 to 0xf143a000)
9d40:                   000000c0 00000001 c238f000 bf0b400c f0d75150 c4816b80
9d60: 00000100 bf0a98d8 00000000 00000000 00000000 00000000 00000000 00000000
9d80: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
9da0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
9dc0: 00000dc0 5335509c 00000035 c238f000 bf0b2214 01067f50 f0d75000 c0b9b9c8
9de0: 0000001d 00000035 c2212094 5335509c c4816b80 c238f000 c5ad6e00 01067f50
9e00: c1b0be80 c4816b80 00014813 c0b9d7f0 00000000 00000000 0000001d 0000001d
9e20: 00000000 00001200 00000000 00000000 c216ed90 c73943b8 00000000 00000000
9e40: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
9e60: 00000000 c0ad9034 00000000 00000000 00000000 00000000 00000000 00000000
9e80: 00000000 00000000 00000000 5335509c c1b0be80 f1439ee4 00008946 c1b0be80
9ea0: 01067f50 f1439ee3 00000000 00000046 b6d77ae0 c0b383f0 00008946 becc83e8
9ec0: c1b0be80 00000051 0000000b c68ca480 c7172d00 c0ad8ff0 f1439ee3 cf600e40
9ee0: 01600e40 32687465 00000000 00000000 00000000 01067f50 00000000 00000000
9f00: 00000000 5335509c 00008946 00008946 00000000 c68ca480 becc83e8 c05e2de0
9f20: f1439fb0 c03002f0 00000006 5ac3c35a c4816b80 00000006 b6d77ae0 c030caf0
9f40: c4817350 00000014 f1439e1c 0000000c 00000000 00000051 01000000 00000014
9f60: 00003fec f1439edc 00000001 c0372abc b6d77ae0 c0372abc cf600e40 5335509c
9f80: c21e6800 01015c9c 0000000b 00008946 00000036 c03002f0 c4816b80 00000036
9fa0: b6d77ae0 c03000c0 01015c9c 0000000b 0000000b 00008946 becc83e8 00000000
9fc0: 01015c9c 0000000b 00008946 00000036 00000035 010678a0 b6d797ec b6d77ae0
9fe0: b6dbf738 becc838c b6d186d7 b6baa858 40000030 0000000b 00000000 00000000
 page_pool_get_stats from mvneta_ethtool_get_stats+0xa0/0xe0 [mvneta]
 mvneta_ethtool_get_stats [mvneta] from ethtool_get_stats+0x154/0x208
 ethtool_get_stats from dev_ethtool+0xf48/0x2480
 dev_ethtool from dev_ioctl+0x538/0x63c
 dev_ioctl from sock_ioctl+0x49c/0x53c
 sock_ioctl from sys_ioctl+0x134/0xbd8
 sys_ioctl from ret_fast_syscall+0x0/0x1c
Exception stack(0xf1439fa8 to 0xf1439ff0)
9fa0:                   01015c9c 0000000b 0000000b 00008946 becc83e8 00000000
9fc0: 01015c9c 0000000b 00008946 00000036 00000035 010678a0 b6d797ec b6d77ae0
9fe0: b6dbf738 becc838c b6d186d7 b6baa858
Code: e28dd004 e1a05000 e2514000 0a00006a (e5902070)

This commit adds the proper checks before calling page_pool_get_stats.

Fixes: b3fc7922 ("net: mvneta: add support for page_pool_get_stats")
Signed-off-by: default avatarSven Auhagen <sven.auhagen@voleatech.de>
Reported-by: default avatarPaulo Da Silva <Paulo.DaSilva@kyberna.com>
Acked-by: default avatarLorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      ca8add92
    • Shigeru Yoshida's avatar
      tipc: Fix kernel-infoleak due to uninitialized TLV value · fb317eb2
      Shigeru Yoshida authored 
      

KMSAN reported the following kernel-infoleak issue:

=====================================================
BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak in copy_to_user_iter lib/iov_iter.c:24 [inline]
BUG: KMSAN: kernel-infoleak in iterate_ubuf include/linux/iov_iter.h:29 [inline]
BUG: KMSAN: kernel-infoleak in iterate_and_advance2 include/linux/iov_iter.h:245 [inline]
BUG: KMSAN: kernel-infoleak in iterate_and_advance include/linux/iov_iter.h:271 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x4ec/0x2bc0 lib/iov_iter.c:186
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 copy_to_user_iter lib/iov_iter.c:24 [inline]
 iterate_ubuf include/linux/iov_iter.h:29 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:245 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 _copy_to_iter+0x4ec/0x2bc0 lib/iov_iter.c:186
 copy_to_iter include/linux/uio.h:197 [inline]
 simple_copy_to_iter net/core/datagram.c:532 [inline]
 __skb_datagram_iter.5+0x148/0xe30 net/core/datagram.c:420
 skb_copy_datagram_iter+0x52/0x210 net/core/datagram.c:546
 skb_copy_datagram_msg include/linux/skbuff.h:3960 [inline]
 netlink_recvmsg+0x43d/0x1630 net/netlink/af_netlink.c:1967
 sock_recvmsg_nosec net/socket.c:1044 [inline]
 sock_recvmsg net/socket.c:1066 [inline]
 __sys_recvfrom+0x476/0x860 net/socket.c:2246
 __do_sys_recvfrom net/socket.c:2264 [inline]
 __se_sys_recvfrom net/socket.c:2260 [inline]
 __x64_sys_recvfrom+0x130/0x200 net/socket.c:2260
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at:
 slab_post_alloc_hook+0x103/0x9e0 mm/slab.h:768
 slab_alloc_node mm/slub.c:3478 [inline]
 kmem_cache_alloc_node+0x5f7/0xb50 mm/slub.c:3523
 kmalloc_reserve+0x13c/0x4a0 net/core/skbuff.c:560
 __alloc_skb+0x2fd/0x770 net/core/skbuff.c:651
 alloc_skb include/linux/skbuff.h:1286 [inline]
 tipc_tlv_alloc net/tipc/netlink_compat.c:156 [inline]
 tipc_get_err_tlv+0x90/0x5d0 net/tipc/netlink_compat.c:170
 tipc_nl_compat_recv+0x1042/0x15d0 net/tipc/netlink_compat.c:1324
 genl_family_rcv_msg_doit net/netlink/genetlink.c:972 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:1052 [inline]
 genl_rcv_msg+0x1220/0x12c0 net/netlink/genetlink.c:1067
 netlink_rcv_skb+0x4a4/0x6a0 net/netlink/af_netlink.c:2545
 genl_rcv+0x41/0x60 net/netlink/genetlink.c:1076
 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline]
 netlink_unicast+0xf4b/0x1230 net/netlink/af_netlink.c:1368
 netlink_sendmsg+0x1242/0x1420 net/netlink/af_netlink.c:1910
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x997/0xd60 net/socket.c:2588
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2642
 __sys_sendmsg net/socket.c:2671 [inline]
 __do_sys_sendmsg net/socket.c:2680 [inline]
 __se_sys_sendmsg net/socket.c:2678 [inline]
 __x64_sys_sendmsg+0x2fa/0x4a0 net/socket.c:2678
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Bytes 34-35 of 36 are uninitialized
Memory access of size 36 starts at ffff88802d464a00
Data copied to user address 00007ff55033c0a0

CPU: 0 PID: 30322 Comm: syz-executor.0 Not tainted 6.6.0-14500-g1c41041124bd #10
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-1.fc38 04/01/2014
=====================================================

tipc_add_tlv() puts TLV descriptor and value onto `skb`. This size is
calculated with TLV_SPACE() macro. It adds the size of struct tlv_desc and
the length of TLV value passed as an argument, and aligns the result to a
multiple of TLV_ALIGNTO, i.e., a multiple of 4 bytes.

If the size of struct tlv_desc plus the length of TLV value is not aligned,
the current implementation leaves the remaining bytes uninitialized. This
is the cause of the above kernel-infoleak issue.

This patch resolves this issue by clearing data up to an aligned size.

Fixes: d0796d1e ("tipc: convert legacy nl bearer dump to nl compat")
Signed-off-by: default avatarShigeru Yoshida <syoshida@redhat.com>
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      fb317eb2
    • Willem de Bruijn's avatar
      net: gso_test: support CONFIG_MAX_SKB_FRAGS up to 45 · e6daf129
      Willem de Bruijn authored 
      

The test allocs a single page to hold all the frag_list skbs. This
is insufficient on kernels with CONFIG_MAX_SKB_FRAGS=45, due to the
increased skb_shared_info frags[] array length.

        gso_test_func: ASSERTION FAILED at net/core/gso_test.c:210
        Expected alloc_size <= ((1UL) << 12), but
            alloc_size == 5075 (0x13d3)
            ((1UL) << 12) == 4096 (0x1000)

Simplify the logic. Just allocate a page for each frag_list skb.

Fixes: 4688ecb1 ("net: expand skb_segment unit test with frag_list coverage")
Signed-off-by: default avatarWillem de Bruijn <willemb@google.com>
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e6daf129