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alistair23-linux/include
Eric Biggers b74555de21 llc: fix sk_buff leak in llc_conn_service()
syzbot reported:

    BUG: memory leak
    unreferenced object 0xffff88811eb3de00 (size 224):
       comm "syz-executor559", pid 7315, jiffies 4294943019 (age 10.300s)
       hex dump (first 32 bytes):
         00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
         00 a0 38 24 81 88 ff ff 00 c0 f2 15 81 88 ff ff  ..8$............
       backtrace:
         [<000000008d1c66a1>] kmemleak_alloc_recursive  include/linux/kmemleak.h:55 [inline]
         [<000000008d1c66a1>] slab_post_alloc_hook mm/slab.h:439 [inline]
         [<000000008d1c66a1>] slab_alloc_node mm/slab.c:3269 [inline]
         [<000000008d1c66a1>] kmem_cache_alloc_node+0x153/0x2a0 mm/slab.c:3579
         [<00000000447d9496>] __alloc_skb+0x6e/0x210 net/core/skbuff.c:198
         [<000000000cdbf82f>] alloc_skb include/linux/skbuff.h:1058 [inline]
         [<000000000cdbf82f>] llc_alloc_frame+0x66/0x110 net/llc/llc_sap.c:54
         [<000000002418b52e>] llc_conn_ac_send_sabme_cmd_p_set_x+0x2f/0x140  net/llc/llc_c_ac.c:777
         [<000000001372ae17>] llc_exec_conn_trans_actions net/llc/llc_conn.c:475  [inline]
         [<000000001372ae17>] llc_conn_service net/llc/llc_conn.c:400 [inline]
         [<000000001372ae17>] llc_conn_state_process+0x1ac/0x640  net/llc/llc_conn.c:75
         [<00000000f27e53c1>] llc_establish_connection+0x110/0x170  net/llc/llc_if.c:109
         [<00000000291b2ca0>] llc_ui_connect+0x10e/0x370 net/llc/af_llc.c:477
         [<000000000f9c740b>] __sys_connect+0x11d/0x170 net/socket.c:1840
         [...]

The bug is that most callers of llc_conn_send_pdu() assume it consumes a
reference to the skb, when actually due to commit b85ab56c3f ("llc:
properly handle dev_queue_xmit() return value") it doesn't.

Revert most of that commit, and instead make the few places that need
llc_conn_send_pdu() to *not* consume a reference call skb_get() before.

Fixes: b85ab56c3f ("llc: properly handle dev_queue_xmit() return value")
Reported-by: syzbot+6b825a6494a04cc0e3f7@syzkaller.appspotmail.com
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-08 13:23:05 -07:00
..
acpi ACPI updates for 5.4-rc1 2019-09-17 19:31:36 -07:00
asm-generic Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2019-09-28 08:14:15 -07:00
clocksource
crypto Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity 2019-09-27 19:37:27 -07:00
drm drm: Measure Self Refresh Entry/Exit times to avoid thrashing 2019-09-19 10:03:32 -04:00
dt-bindings Main MIPS changes for v5.4: 2019-09-22 09:30:30 -07:00
keys
kvm
linux Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-10-05 08:50:15 -07:00
math-emu
media
misc
net llc: fix sk_buff leak in llc_conn_service() 2019-10-08 13:23:05 -07:00
pcmcia
ras
rdma RDMA subsystem updates for 5.4 2019-09-21 10:26:24 -07:00
scsi SCSI misc on 20190919 2019-09-21 10:50:15 -07:00
soc Char/Misc driver patches for 5.4-rc1 2019-09-18 11:14:31 -07:00
sound ASoC: Updates for v5.4 2019-09-10 13:03:08 +02:00
target
trace rxrpc: Fix trace-after-put looking at the put call record 2019-10-07 11:05:05 +01:00
uapi copy-struct-from-user-v5.4-rc2 2019-10-04 10:36:31 -07:00
vdso
video
xen xen: fixes and cleanups for 5.4-rc2 2019-10-04 11:13:09 -07:00
Kbuild - New Drivers 2019-09-23 19:37:49 -07:00