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Mauro Carvalho Chehab 85ea29f19e media: v4l2-compat-ioctl32: don't oops on overlay
At put_v4l2_window32(), it tries to access kp->clips. However,
kp points to an userspace pointer. So, it should be obtained
via get_user(), otherwise it can OOPS:

 vivid-000: ==================  END STATUS  ==================
 BUG: unable to handle kernel paging request at 00000000fffb18e0
 IP: [<ffffffffc05468d9>] __put_v4l2_format32+0x169/0x220 [videodev]
 PGD 3f5776067 PUD 3f576f067 PMD 3f5769067 PTE 800000042548f067
 Oops: 0001 [#1] SMP
 Modules linked in: vivid videobuf2_vmalloc videobuf2_memops v4l2_dv_timings videobuf2_core v4l2_common videodev media xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack tun bridge stp llc ebtable_filter ebtables ip6table_filter ip6_tables bluetooth rfkill binfmt_misc snd_hda_codec_hdmi i915 snd_hda_intel snd_hda_controller snd_hda_codec intel_rapl x86_pkg_temp_thermal snd_hwdep intel_powerclamp snd_pcm coretemp snd_seq_midi kvm_intel kvm snd_seq_midi_event snd_rawmidi i2c_algo_bit drm_kms_helper snd_seq drm crct10dif_pclmul e1000e snd_seq_device crc32_pclmul snd_timer ghash_clmulni_intel snd mei_me mei ptp pps_core soundcore lpc_ich video crc32c_intel [last unloaded: media]
 CPU: 2 PID: 28332 Comm: v4l2-compliance Not tainted 3.18.102+ #107
 Hardware name:                  /NUC5i7RYB, BIOS RYBDWi35.86A.0364.2017.0511.0949 05/11/2017
 task: ffff8804293f8000 ti: ffff8803f5640000 task.ti: ffff8803f5640000
 RIP: 0010:[<ffffffffc05468d9>]  [<ffffffffc05468d9>] __put_v4l2_format32+0x169/0x220 [videodev]
 RSP: 0018:ffff8803f5643e28  EFLAGS: 00010246
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00000000fffb1ab4
 RDX: 00000000fffb1a68 RSI: 00000000fffb18d8 RDI: 00000000fffb1aa8
 RBP: ffff8803f5643e48 R08: 0000000000000001 R09: ffff8803f54b0378
 R10: 0000000000000000 R11: 0000000000000168 R12: 00000000fffb18c0
 R13: 00000000fffb1a94 R14: 00000000fffb18c8 R15: 0000000000000000
 FS:  0000000000000000(0000) GS:ffff880456d00000(0063) knlGS:00000000f7100980
 CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
 CR2: 00000000fffb18e0 CR3: 00000003f552b000 CR4: 00000000003407e0
 Stack:
  00000000fffb1a94 00000000c0cc5640 0000000000000056 ffff8804274f3600
  ffff8803f5643ed0 ffffffffc0547e16 0000000000000003 ffff8803f5643eb0
  ffffffff81301460 ffff88009db44b01 ffff880441942520 ffff8800c0d05640
 Call Trace:
  [<ffffffffc0547e16>] v4l2_compat_ioctl32+0x12d6/0x1b1d [videodev]
  [<ffffffff81301460>] ? file_has_perm+0x70/0xc0
  [<ffffffff81252a2c>] compat_SyS_ioctl+0xec/0x1200
  [<ffffffff8173241a>] sysenter_dispatch+0x7/0x21
 Code: 00 00 48 8b 80 48 c0 ff ff 48 83 e8 38 49 39 c6 0f 87 2b ff ff ff 49 8d 45 1c e8 a3 ce e3 c0 85 c0 0f 85 1a ff ff ff 41 8d 40 ff <4d> 8b 64 24 20 41 89 d5 48 8d 44 40 03 4d 8d 34 c4 eb 15 0f 1f
 RIP  [<ffffffffc05468d9>] __put_v4l2_format32+0x169/0x220 [videodev]
 RSP <ffff8803f5643e28>
 CR2: 00000000fffb18e0

Tested with vivid driver on Kernel v3.18.102.

Same bug happens upstream too:

 BUG: KASAN: user-memory-access in __put_v4l2_format32+0x98/0x4d0 [videodev]
 Read of size 8 at addr 00000000ffe48400 by task v4l2-compliance/8713

 CPU: 0 PID: 8713 Comm: v4l2-compliance Not tainted 4.16.0-rc4+ #108
 Hardware name:  /NUC5i7RYB, BIOS RYBDWi35.86A.0364.2017.0511.0949 05/11/2017
 Call Trace:
  dump_stack+0x5c/0x7c
  kasan_report+0x164/0x380
  ? __put_v4l2_format32+0x98/0x4d0 [videodev]
  __put_v4l2_format32+0x98/0x4d0 [videodev]
  v4l2_compat_ioctl32+0x1aec/0x27a0 [videodev]
  ? __fsnotify_inode_delete+0x20/0x20
  ? __put_v4l2_format32+0x4d0/0x4d0 [videodev]
  compat_SyS_ioctl+0x646/0x14d0
  ? do_ioctl+0x30/0x30
  do_fast_syscall_32+0x191/0x3f4
  entry_SYSENTER_compat+0x6b/0x7a
 ==================================================================
 Disabling lock debugging due to kernel taint
 BUG: unable to handle kernel paging request at 00000000ffe48400
 IP: __put_v4l2_format32+0x98/0x4d0 [videodev]
 PGD 3a22fb067 P4D 3a22fb067 PUD 39b6f0067 PMD 39b6f1067 PTE 80000003256af067
 Oops: 0001 [#1] SMP KASAN
 Modules linked in: vivid videobuf2_vmalloc videobuf2_dma_contig videobuf2_memops v4l2_tpg v4l2_dv_timings videobuf2_v4l2 videobuf2_common v4l2_common videodev xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack libcrc32c tun bridge stp llc ebtable_filter ebtables ip6table_filter ip6_tables bluetooth rfkill ecdh_generic binfmt_misc snd_hda_codec_hdmi intel_rapl x86_pkg_temp_thermal intel_powerclamp i915 coretemp snd_hda_intel snd_hda_codec kvm_intel snd_hwdep snd_hda_core kvm snd_pcm irqbypass crct10dif_pclmul crc32_pclmul snd_seq_midi ghash_clmulni_intel snd_seq_midi_event i2c_algo_bit intel_cstate snd_rawmidi intel_uncore snd_seq drm_kms_helper e1000e snd_seq_device snd_timer intel_rapl_perf
  drm ptp snd mei_me mei lpc_ich pps_core soundcore video crc32c_intel
 CPU: 0 PID: 8713 Comm: v4l2-compliance Tainted: G    B            4.16.0-rc4+ #108
 Hardware name:  /NUC5i7RYB, BIOS RYBDWi35.86A.0364.2017.0511.0949 05/11/2017
 RIP: 0010:__put_v4l2_format32+0x98/0x4d0 [videodev]
 RSP: 0018:ffff8803b9be7d30 EFLAGS: 00010282
 RAX: 0000000000000000 RBX: ffff8803ac983e80 RCX: ffffffff8cd929f2
 RDX: 1ffffffff1d0a149 RSI: 0000000000000297 RDI: 0000000000000297
 RBP: 00000000ffe485c0 R08: fffffbfff1cf5123 R09: ffffffff8e7a8948
 R10: 0000000000000001 R11: fffffbfff1cf5122 R12: 00000000ffe483e0
 R13: 00000000ffe485c4 R14: ffff8803ac985918 R15: 00000000ffe483e8
 FS:  0000000000000000(0000) GS:ffff880407400000(0063) knlGS:00000000f7a46980
 CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
 CR2: 00000000ffe48400 CR3: 00000003a83f2003 CR4: 00000000003606f0
 Call Trace:
  v4l2_compat_ioctl32+0x1aec/0x27a0 [videodev]
  ? __fsnotify_inode_delete+0x20/0x20
  ? __put_v4l2_format32+0x4d0/0x4d0 [videodev]
  compat_SyS_ioctl+0x646/0x14d0
  ? do_ioctl+0x30/0x30
  do_fast_syscall_32+0x191/0x3f4
  entry_SYSENTER_compat+0x6b/0x7a
 Code: 4c 89 f7 4d 8d 7c 24 08 e8 e6 a4 69 cb 48 8b 83 98 1a 00 00 48 83 e8 10 49 39 c7 0f 87 9d 01 00 00 49 8d 7c 24 20 e8 c8 a4 69 cb <4d> 8b 74 24 20 4c 89 ef 4c 89 fe ba 10 00 00 00 e8 23 d9 08 cc
 RIP: __put_v4l2_format32+0x98/0x4d0 [videodev] RSP: ffff8803b9be7d30
 CR2: 00000000ffe48400

cc: stable@vger.kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-04-05 05:30:15 -04:00
Documentation media: extended-controls.rst: transmitter -> receiver 2018-04-04 08:05:20 -04:00
LICENSES LICENSES: Add MPL-1.1 license 2018-01-06 10:59:44 -07:00
arch media updates for v4.17-rc1 2018-04-03 17:16:59 -07:00
block treewide: simplify Kconfig dependencies for removed archs 2018-03-26 15:55:57 +02:00
certs certs/blacklist_nohashes.c: fix const confusion in certs blacklist 2018-02-21 15:35:43 -08:00
crypto mn10300: Remove the architecture 2018-03-09 23:19:56 +01:00
drivers media: v4l2-compat-ioctl32: don't oops on overlay 2018-04-05 05:30:15 -04:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs Merge branch 'for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq 2018-04-03 18:00:13 -07:00
include media: v4l: Bring back array_size parameter to v4l2_find_nearest_size 2018-04-04 06:12:53 -04:00
init Merge branch 'syscalls-next' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux 2018-04-02 21:22:12 -07:00
ipc Merge branch 'userns-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2018-04-03 19:15:32 -07:00
kernel Merge branch 'userns-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2018-04-03 19:15:32 -07:00
lib Kbuild updates for v4.17 2018-04-03 15:51:22 -07:00
mm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next 2018-04-03 14:08:58 -07:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-04-03 14:04:18 -07:00
samples Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-04-03 14:04:18 -07:00
scripts Kconfig updates for v4.17 2018-04-03 16:28:01 -07:00
security Merge branch 'userns-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2018-04-03 19:15:32 -07:00
sound Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-04-03 14:04:18 -07:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-04-03 14:04:18 -07:00
usr kbuild: rename built-in.o to built-in.a 2018-03-26 02:01:19 +09:00
virt kvm/arm fixes for 4.16, take 2 2018-03-15 21:45:37 +01:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: move include/config/ksym/* to include/ksym/* 2018-03-26 02:01:23 +09:00
.mailmap Merge remote-tracking branch 'spi/topic/samsung' into spi-next 2018-04-02 15:56:32 +01:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS/CREDITS: Drop METAG ARCHITECTURE 2018-03-05 16:34:24 +00:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
MAINTAINERS media updates for v4.17-rc1 2018-04-03 17:16:59 -07:00
Makefile Kconfig updates for v4.17 2018-04-03 16:28:01 -07:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.