linux-stable.git/net/socket.c, branch linux-3.18.y

net: socket: fix a missing-check bug

2018-11-10T15:39:22+00:00

[ Upstream commit b6168562c8ce2bd5a30e213021650422e08764dc ]

In ethtool_ioctl(), the ioctl command 'ethcmd' is checked through a switch
statement to see whether it is necessary to pre-process the ethtool
structure, because, as mentioned in the comment, the structure
ethtool_rxnfc is defined with padding. If yes, a user-space buffer 'rxnfc'
is allocated through compat_alloc_user_space(). One thing to note here is
that, if 'ethcmd' is ETHTOOL_GRXCLSRLALL, the size of the buffer 'rxnfc' is
partially determined by 'rule_cnt', which is actually acquired from the
user-space buffer 'compat_rxnfc', i.e., 'compat_rxnfc->rule_cnt', through
get_user(). After 'rxnfc' is allocated, the data in the original user-space
buffer 'compat_rxnfc' is then copied to 'rxnfc' through copy_in_user(),
including the 'rule_cnt' field. However, after this copy, no check is
re-enforced on 'rxnfc->rule_cnt'. So it is possible that a malicious user
race to change the value in the 'compat_rxnfc->rule_cnt' between these two
copies. Through this way, the attacker can bypass the previous check on
'rule_cnt' and inject malicious data. This can cause undefined behavior of
the kernel and introduce potential security risk.

This patch avoids the above issue via copying the value acquired by
get_user() to 'rxnfc->rule_cn', if 'ethcmd' is ETHTOOL_GRXCLSRLALL.

Signed-off-by: Wenwen Wang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: socket: fix recvmmsg not returning error from sock_error

2017-04-18T05:55:48+00:00

[ Upstream commit e623a9e9dec29ae811d11f83d0074ba254aba374 ]

Commit 34b88a68f26a ("net: Fix use after free in the recvmmsg exit path"),
changed the exit path of recvmmsg to always return the datagrams
variable and modified the error paths to set the variable to the error
code returned by recvmsg if necessary.

However in the case sock_error returned an error, the error code was
then ignored, and recvmmsg returned 0.

Change the error path of recvmmsg to correctly return the error code
of sock_error.

The bug was triggered by using recvmmsg on a CAN interface which was
not up. Linux 4.6 and later return 0 in this case while earlier
releases returned -ENETDOWN.

Fixes: 34b88a68f26a ("net: Fix use after free in the recvmmsg exit path")
Signed-off-by: Maxime Jayat 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: Fix use after free in the recvmmsg exit path

2016-07-12T12:47:36+00:00

[ Upstream commit 34b88a68f26a75e4fded796f1a49c40f82234b7d ]

The syzkaller fuzzer hit the following use-after-free:

  Call Trace:
   [] __asan_report_load8_noabort+0x3e/0x40 mm/kasan/report.c:295
   [] __sys_recvmmsg+0x6fa/0x7f0 net/socket.c:2261
   [<     inline     >] SYSC_recvmmsg net/socket.c:2281
   [] SyS_recvmmsg+0x16f/0x180 net/socket.c:2270
   [] entry_SYSCALL_64_fastpath+0x16/0x7a
  arch/x86/entry/entry_64.S:185

And, as Dmitry rightly assessed, that is because we can drop the
reference and then touch it when the underlying recvmsg calls return
some packets and then hit an error, which will make recvmmsg to set
sock->sk->sk_err, oops, fix it.

Reported-and-Tested-by: Dmitry Vyukov 
Cc: Alexander Potapenko 
Cc: Eric Dumazet 
Cc: Kostya Serebryany 
Cc: Sasha Levin 
Fixes: a2e2725541fa ("net: Introduce recvmmsg socket syscall")
http://lkml.kernel.org/r/20160122211644.GC2470@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: socket: Fix the wrong returns for recvmsg and sendmsg

2015-07-03T16:34:30+00:00

[ Upstream commit HEAD ]

Based on 08adb7dabd4874cc5666b4490653b26534702ce0 upstream.

We found that after v3.10.73, recvmsg might return -EFAULT while -EINVAL
was expected.

We tested it through the recvmsg01 testcase come from LTP testsuit. It set
msg->msg_namelen to -1 and the recvmsg syscall returned errno 14, which is
unexpected (errno 22 is expected):

recvmsg01    4  TFAIL  :  invalid socket length ; returned -1 (expected -1),
errno 14 (expected 22)

Linux mainline has no this bug for commit 08adb7dab fixes it accidentally.
However, it is too large and complex to be backported to LTS 3.10.

Commit 281c9c36 (net: compat: Update get_compat_msghdr() to match
copy_msghdr_from_user() behaviour) made get_compat_msghdr() return
error if msg_sys->msg_namelen was negative, which changed the behaviors
of recvmsg and sendmsg syscall in a lib32 system:

Before commit 281c9c36, get_compat_msghdr() wouldn't fail and it would
return -EINVAL in move_addr_to_user() or somewhere if msg_sys->msg_namelen
was invalid and then syscall returned -EINVAL, which is correct.

And now, when msg_sys->msg_namelen is negative, get_compat_msghdr() will
fail and wants to return -EINVAL, however, the outer syscall will return
-EFAULT directly, which is unexpected.

This patch gets the return value of get_compat_msghdr() as well as
copy_msghdr_from_user(), then returns this expected value if
get_compat_msghdr() fails.

Fixes: 281c9c36 (net: compat: Update get_compat_msghdr() to match copy_msghdr_from_user() behaviour)
Signed-off-by: Junling Zheng 
Signed-off-by: Hanbing Xu 
Cc: Li Zefan 
Cc: Al Viro 
Cc: David Miller 
Signed-off-by: Greg Kroah-Hartman 

(cherry picked from commit 5ca74d43d929e6ecaba677a411f0e81371d61f76)
Signed-off-by: Sasha Levin

net: don't OOPS on socket aio

2015-02-27T01:49:01+00:00

[ Upstream commit 06539d3071067ff146a9bffd1c801fa56d290909 ]

Signed-off-by: Christoph Hellwig 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'locks-v3.18-1' of git://git.samba.org/jlayton/linux

2014-10-11T17:21:34+00:00

Pull file locking related changes from Jeff Layton:
 "This release is a little more busy for file locking changes than the
  last:

   - a set of patches from Kinglong Mee to fix the lockowner handling in
     knfsd
   - a pile of cleanups to the internal file lease API.  This should get
     us a bit closer to allowing for setlease methods that can block.

  There are some dependencies between mine and Bruce's trees this cycle,
  and I based my tree on top of the requisite patches in Bruce's tree"

* tag 'locks-v3.18-1' of git://git.samba.org/jlayton/linux: (26 commits)
  locks: fix fcntl_setlease/getlease return when !CONFIG_FILE_LOCKING
  locks: flock_make_lock should return a struct file_lock (or PTR_ERR)
  locks: set fl_owner for leases to filp instead of current->files
  locks: give lm_break a return value
  locks: __break_lease cleanup in preparation of allowing direct removal of leases
  locks: remove i_have_this_lease check from __break_lease
  locks: move freeing of leases outside of i_lock
  locks: move i_lock acquisition into generic_*_lease handlers
  locks: define a lm_setup handler for leases
  locks: plumb a "priv" pointer into the setlease routines
  nfsd: don't keep a pointer to the lease in nfs4_file
  locks: clean up vfs_setlease kerneldoc comments
  locks: generic_delete_lease doesn't need a file_lock at all
  nfsd: fix potential lease memory leak in nfs4_setlease
  locks: close potential race in lease_get_mtime
  security: make security_file_set_fowner, f_setown and __f_setown void return
  locks: consolidate "nolease" routines
  locks: remove lock_may_read and lock_may_write
  lockd: rip out deferred lock handling from testlock codepath
  NFSD: Get reference of lockowner when coping file_lock
  ...

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2014-09-23T16:09:27+00:00

Conflicts:
	arch/mips/net/bpf_jit.c
	drivers/net/can/flexcan.c

Both the flexcan and MIPS bpf_jit conflicts were cases of simple
overlapping changes.

Signed-off-by: David S. Miller

net:socket: set msg_namelen to 0 if msg_name is passed as NULL in msghdr struct from userland.

2014-09-10T00:35:46+00:00

Linux manpage for recvmsg and sendmsg calls does not explicitly mention setting msg_namelen to 0 when
msg_name passed set as NULL. When developers don't set msg_namelen member in msghdr, it might contain garbage
value which will fail the validation check and sendmsg and recvmsg calls from kernel will return EINVAL. This will
break old binaries and any code for which there is no access to source code.
To fix this, we set msg_namelen to 0 when msg_name is passed as NULL from userland.

Signed-off-by: Ani Sinha 
Signed-off-by: David S. Miller

net-timestamp: optimize sock_tx_timestamp default path

2014-09-10T00:34:41+00:00

Few packets have timestamping enabled. Exit sock_tx_timestamp quickly
in this common case.

Signed-off-by: Willem de Bruijn 
Signed-off-by: David S. Miller

security: make security_file_set_fowner, f_setown and __f_setown void return

2014-09-09T20:01:36+00:00

security_file_set_fowner always returns 0, so make it f_setown and
__f_setown void return functions and fix up the error handling in the
callers.

Cc: linux-security-module@vger.kernel.org
Signed-off-by: Jeff Layton 
Reviewed-by: Christoph Hellwig