linux/net/phonet
Sasha Levin bcf1b70ac6 phonet: Check input from user before allocating
A phonet packet is limited to USHRT_MAX bytes, this is never checked during
tx which means that the user can specify any size he wishes, and the kernel
will attempt to allocate that size.

In the good case, it'll lead to the following warning, but it may also cause
the kernel to kick in the OOM and kill a random task on the server.

[ 8921.744094] WARNING: at mm/page_alloc.c:2255 __alloc_pages_slowpath+0x65/0x730()
[ 8921.749770] Pid: 5081, comm: trinity Tainted: G        W    3.4.0-rc1-next-20120402-sasha #46
[ 8921.756672] Call Trace:
[ 8921.758185]  [<ffffffff810b2ba7>] warn_slowpath_common+0x87/0xb0
[ 8921.762868]  [<ffffffff810b2be5>] warn_slowpath_null+0x15/0x20
[ 8921.765399]  [<ffffffff8117eae5>] __alloc_pages_slowpath+0x65/0x730
[ 8921.769226]  [<ffffffff81179c8a>] ? zone_watermark_ok+0x1a/0x20
[ 8921.771686]  [<ffffffff8117d045>] ? get_page_from_freelist+0x625/0x660
[ 8921.773919]  [<ffffffff8117f3a8>] __alloc_pages_nodemask+0x1f8/0x240
[ 8921.776248]  [<ffffffff811c03e0>] kmalloc_large_node+0x70/0xc0
[ 8921.778294]  [<ffffffff811c4bd4>] __kmalloc_node_track_caller+0x34/0x1c0
[ 8921.780847]  [<ffffffff821b0e3c>] ? sock_alloc_send_pskb+0xbc/0x260
[ 8921.783179]  [<ffffffff821b3c65>] __alloc_skb+0x75/0x170
[ 8921.784971]  [<ffffffff821b0e3c>] sock_alloc_send_pskb+0xbc/0x260
[ 8921.787111]  [<ffffffff821b002e>] ? release_sock+0x7e/0x90
[ 8921.788973]  [<ffffffff821b0ff0>] sock_alloc_send_skb+0x10/0x20
[ 8921.791052]  [<ffffffff824cfc20>] pep_sendmsg+0x60/0x380
[ 8921.792931]  [<ffffffff824cb4a6>] ? pn_socket_bind+0x156/0x180
[ 8921.794917]  [<ffffffff824cb50f>] ? pn_socket_autobind+0x3f/0x90
[ 8921.797053]  [<ffffffff824cb63f>] pn_socket_sendmsg+0x4f/0x70
[ 8921.798992]  [<ffffffff821ab8e7>] sock_aio_write+0x187/0x1b0
[ 8921.801395]  [<ffffffff810e325e>] ? sub_preempt_count+0xae/0xf0
[ 8921.803501]  [<ffffffff8111842c>] ? __lock_acquire+0x42c/0x4b0
[ 8921.805505]  [<ffffffff821ab760>] ? __sock_recv_ts_and_drops+0x140/0x140
[ 8921.807860]  [<ffffffff811e07cc>] do_sync_readv_writev+0xbc/0x110
[ 8921.809986]  [<ffffffff811958e7>] ? might_fault+0x97/0xa0
[ 8921.811998]  [<ffffffff817bd99e>] ? security_file_permission+0x1e/0x90
[ 8921.814595]  [<ffffffff811e17e2>] do_readv_writev+0xe2/0x1e0
[ 8921.816702]  [<ffffffff810b8dac>] ? do_setitimer+0x1ac/0x200
[ 8921.818819]  [<ffffffff810e2ec1>] ? get_parent_ip+0x11/0x50
[ 8921.820863]  [<ffffffff810e325e>] ? sub_preempt_count+0xae/0xf0
[ 8921.823318]  [<ffffffff811e1926>] vfs_writev+0x46/0x60
[ 8921.825219]  [<ffffffff811e1a3f>] sys_writev+0x4f/0xb0
[ 8921.827127]  [<ffffffff82658039>] system_call_fastpath+0x16/0x1b
[ 8921.829384] ---[ end trace dffe390f30db9eb7 ]---

Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Acked-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-05 19:05:56 -04:00
..
af_phonet.c net: reintroduce missing rcu_assign_pointer() calls 2012-01-12 12:26:56 -08:00
datagram.c net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules 2011-10-31 19:30:30 -04:00
Kconfig Phonet: kill the ST-Ericsson pipe controller Kconfig 2011-03-09 11:59:33 -08:00
Makefile Net: phonet: Makefile: Remove deprecated kbuild goal definitions 2010-11-22 08:16:14 -08:00
pep-gprs.c Phonet: zero-copy aligned GPRS RX 2010-01-07 00:24:54 -08:00
pep.c phonet: Check input from user before allocating 2012-04-05 19:05:56 -04:00
pn_dev.c net: reintroduce missing rcu_assign_pointer() calls 2012-01-12 12:26:56 -08:00
pn_netlink.c rtnetlink: Compute and store minimum ifinfo dump size 2011-06-09 20:38:07 -07:00
socket.c net: reintroduce missing rcu_assign_pointer() calls 2012-01-12 12:26:56 -08:00
sysctl.c sysctl net: Remove unused binary sysctl code 2009-11-12 02:05:06 -08:00