linux/include
Subash Abhinov Kasiviswanathan 70cd763eb1 sysctl: handle error writing UINT_MAX to u32 fields
commit e7d316a02f upstream.

We have scripts which write to certain fields on 3.18 kernels but this
seems to be failing on 4.4 kernels.  An entry which we write to here is
xfrm_aevent_rseqth which is u32.

  echo 4294967295  > /proc/sys/net/core/xfrm_aevent_rseqth

Commit 230633d109 ("kernel/sysctl.c: detect overflows when converting
to int") prevented writing to sysctl entries when integer overflow
occurs.  However, this does not apply to unsigned integers.

Heinrich suggested that we introduce a new option to handle 64 bit
limits and set min as 0 and max as UINT_MAX.  This might not work as it
leads to issues similar to __do_proc_doulongvec_minmax.  Alternatively,
we would need to change the datatype of the entry to 64 bit.

  static int __do_proc_doulongvec_minmax(void *data, struct ctl_table
  {
      i = (unsigned long *) data;   //This cast is causing to read beyond the size of data (u32)
      vleft = table->maxlen / sizeof(unsigned long); //vleft is 0 because maxlen is sizeof(u32) which is lesser than sizeof(unsigned long) on x86_64.

Introduce a new proc handler proc_douintvec.  Individual proc entries
will need to be updated to use the new handler.

[akpm@linux-foundation.org: coding-style fixes]
Fixes: 230633d109 ("kernel/sysctl.c:detect overflows when converting to int")
Link: http://lkml.kernel.org/r/1471479806-5252-1-git-send-email-subashab@codeaurora.org
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Cc: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-07 15:23:46 +02:00
..
acpi Merge branch 'acpi-pci' 2015-11-07 01:30:10 +01:00
asm-generic asm-generic: make copy_from_user() zero the destination properly 2016-09-24 10:07:45 +02:00
clocksource
crypto crypto: af_alg - Allow af_af_alg_release_parent to be called on nokey path 2016-02-17 12:31:03 -08:00
drm drm/i915/skl: Add missing SKL ids 2016-09-15 08:27:44 +02:00
dt-bindings ARM: DT updates for v4.4 2015-11-10 15:06:26 -08:00
keys
kvm KVM: arm/arm64: arch_timer: Preserve physical dist. active state on LR.active 2015-11-24 18:07:40 +01:00
linux sysctl: handle error writing UINT_MAX to u32 fields 2016-10-07 15:23:46 +02:00
math-emu
media videobuf2-core: Check user space planes array in dqbuf 2016-05-04 14:48:50 -07:00
memory
misc
net af_unix: split 'u->readlock' into two: 'iolock' and 'bindlock' 2016-09-30 10:18:36 +02:00
pcmcia
ras
rdma IB/security: Restrict use of the write() interface 2016-05-04 14:48:48 -07:00
rxrpc
scsi scsi: Add intermediate STARGET_REMOVE state to scsi_target_state 2016-06-01 12:15:54 -07:00
soc ARM: SoC driver updates for v4.4 2015-11-10 15:00:03 -08:00
sound ALSA: rawmidi: Make snd_rawmidi_transmit() race-free 2016-02-17 12:30:58 -08:00
target target: Fix ordered task CHECK_CONDITION early exception handling 2016-08-20 18:09:26 +02:00
trace SUNRPC: Don't allocate a full sockaddr_storage for tracing 2016-08-20 18:09:26 +02:00
uapi cxlflash: Fix to avoid virtual LUN failover failure 2016-09-15 08:27:49 +02:00
video drm/imx: Match imx-ipuv3-crtc components using device node in platform data 2016-06-07 18:14:37 -07:00
xen xen: Fix page <-> pfn conversion on 32 bit systems 2016-05-11 11:21:14 +02:00
Kbuild