<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel.git/fs/f2fs/super.c, branch linux-3.18.y</title>
<subtitle>Hosts the 0x221E linux distro kernel.
</subtitle>
<id>https://git.0xinfinity.dev/distro/kernel.git/atom?h=linux-3.18.y</id>
<link rel='self' href='https://git.0xinfinity.dev/distro/kernel.git/atom?h=linux-3.18.y'/>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/'/>
<updated>2018-09-26T06:33:55Z</updated>
<entry>
<title>f2fs: fix to do sanity check with {sit,nat}_ver_bitmap_bytesize</title>
<updated>2018-09-26T06:33:55Z</updated>
<author>
<name>Chao Yu</name>
</author>
<published>2018-06-23T03:25:19Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=ae3ab8fd4b056dc1827167d90cc4eb6bcafb6933'/>
<id>urn:sha1:ae3ab8fd4b056dc1827167d90cc4eb6bcafb6933</id>
<content type='text'>
[ Upstream commit c77ec61ca0a49544ca81881cc5d5529858f7e196 ]

This patch adds to do sanity check with {sit,nat}_ver_bitmap_bytesize
during mount, in order to avoid accessing across cache boundary with
this abnormal bitmap size.

- Overview
buffer overrun in build_sit_info() when mounting a crafted f2fs image

- Reproduce

- Kernel message
[  548.580867] F2FS-fs (loop0): Invalid log blocks per segment (8201)

[  548.580877] F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
[  548.584979] ==================================================================
[  548.586568] BUG: KASAN: use-after-free in kmemdup+0x36/0x50
[  548.587715] Read of size 64 at addr ffff8801e9c265ff by task mount/1295

[  548.589428] CPU: 1 PID: 1295 Comm: mount Not tainted 4.18.0-rc1+ #4
[  548.589432] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
[  548.589438] Call Trace:
[  548.589474]  dump_stack+0x7b/0xb5
[  548.589487]  print_address_description+0x70/0x290
[  548.589492]  kasan_report+0x291/0x390
[  548.589496]  ? kmemdup+0x36/0x50
[  548.589509]  check_memory_region+0x139/0x190
[  548.589514]  memcpy+0x23/0x50
[  548.589518]  kmemdup+0x36/0x50
[  548.589545]  f2fs_build_segment_manager+0x8fa/0x3410
[  548.589551]  ? __asan_loadN+0xf/0x20
[  548.589560]  ? f2fs_sanity_check_ckpt+0x1be/0x240
[  548.589566]  ? f2fs_flush_sit_entries+0x10c0/0x10c0
[  548.589587]  ? __put_user_ns+0x40/0x40
[  548.589604]  ? find_next_bit+0x57/0x90
[  548.589610]  f2fs_fill_super+0x194b/0x2b40
[  548.589617]  ? f2fs_commit_super+0x1b0/0x1b0
[  548.589637]  ? set_blocksize+0x90/0x140
[  548.589651]  mount_bdev+0x1c5/0x210
[  548.589655]  ? f2fs_commit_super+0x1b0/0x1b0
[  548.589667]  f2fs_mount+0x15/0x20
[  548.589672]  mount_fs+0x60/0x1a0
[  548.589683]  ? alloc_vfsmnt+0x309/0x360
[  548.589688]  vfs_kern_mount+0x6b/0x1a0
[  548.589699]  do_mount+0x34a/0x18c0
[  548.589710]  ? lockref_put_or_lock+0xcf/0x160
[  548.589716]  ? copy_mount_string+0x20/0x20
[  548.589728]  ? memcg_kmem_put_cache+0x1b/0xa0
[  548.589734]  ? kasan_check_write+0x14/0x20
[  548.589740]  ? _copy_from_user+0x6a/0x90
[  548.589744]  ? memdup_user+0x42/0x60
[  548.589750]  ksys_mount+0x83/0xd0
[  548.589755]  __x64_sys_mount+0x67/0x80
[  548.589781]  do_syscall_64+0x78/0x170
[  548.589797]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  548.589820] RIP: 0033:0x7f76fc331b9a
[  548.589821] Code: 48 8b 0d 01 c3 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f 05 &lt;48&gt; 3d 01 f0 ff ff 73 01 c3 48 8b 0d ce c2 2b 00 f7 d8 64 89 01 48
[  548.589880] RSP: 002b:00007ffd4f0a0e48 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
[  548.589890] RAX: ffffffffffffffda RBX: 000000000146c030 RCX: 00007f76fc331b9a
[  548.589892] RDX: 000000000146c210 RSI: 000000000146df30 RDI: 0000000001474ec0
[  548.589895] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000013
[  548.589897] R10: 00000000c0ed0000 R11: 0000000000000206 R12: 0000000001474ec0
[  548.589900] R13: 000000000146c210 R14: 0000000000000000 R15: 0000000000000003

[  548.590242] The buggy address belongs to the page:
[  548.591243] page:ffffea0007a70980 count:0 mapcount:0 mapping:0000000000000000 index:0x0
[  548.592886] flags: 0x2ffff0000000000()
[  548.593665] raw: 02ffff0000000000 dead000000000100 dead000000000200 0000000000000000
[  548.595258] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
[  548.603713] page dumped because: kasan: bad access detected

[  548.605203] Memory state around the buggy address:
[  548.606198]  ffff8801e9c26480: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[  548.607676]  ffff8801e9c26500: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[  548.609157] &gt;ffff8801e9c26580: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[  548.610629]                                                                 ^
[  548.612088]  ffff8801e9c26600: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[  548.613674]  ffff8801e9c26680: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[  548.615141] ==================================================================
[  548.616613] Disabling lock debugging due to kernel taint
[  548.622871] WARNING: CPU: 1 PID: 1295 at mm/page_alloc.c:4065 __alloc_pages_slowpath+0xe4a/0x1420
[  548.622878] Modules linked in: snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_pcm snd_timer snd mac_hid i2c_piix4 soundcore ib_iser rdma_cm iw_cm ib_cm ib_core iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx raid1 raid0 multipath linear 8139too crct10dif_pclmul crc32_pclmul qxl drm_kms_helper syscopyarea aesni_intel sysfillrect sysimgblt fb_sys_fops ttm drm aes_x86_64 crypto_simd cryptd 8139cp glue_helper mii pata_acpi floppy
[  548.623217] CPU: 1 PID: 1295 Comm: mount Tainted: G    B             4.18.0-rc1+ #4
[  548.623219] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
[  548.623226] RIP: 0010:__alloc_pages_slowpath+0xe4a/0x1420
[  548.623227] Code: ff ff 01 89 85 c8 fe ff ff e9 91 fc ff ff 41 89 c5 e9 5c fc ff ff 0f 0b 89 f8 25 ff ff f7 ff 89 85 8c fe ff ff e9 d5 f2 ff ff &lt;0f&gt; 0b e9 65 f2 ff ff 65 8b 05 38 81 d2 47 f6 c4 01 74 1c 65 48 8b
[  548.623281] RSP: 0018:ffff8801f28c7678 EFLAGS: 00010246
[  548.623284] RAX: 0000000000000000 RBX: 00000000006040c0 RCX: ffffffffb82f73b7
[  548.623287] RDX: 1ffff1003e518eeb RSI: 000000000000000c RDI: 0000000000000000
[  548.623290] RBP: ffff8801f28c7880 R08: 0000000000000000 R09: ffffed0047fff2c5
[  548.623292] R10: 0000000000000001 R11: ffffed0047fff2c4 R12: ffff8801e88de040
[  548.623295] R13: 00000000006040c0 R14: 000000000000000c R15: ffff8801f28c7938
[  548.623299] FS:  00007f76fca51840(0000) GS:ffff8801f6f00000(0000) knlGS:0000000000000000
[  548.623302] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  548.623304] CR2: 00007f19b9171760 CR3: 00000001ed952000 CR4: 00000000000006e0
[  548.623317] Call Trace:
[  548.623325]  ? kasan_check_read+0x11/0x20
[  548.623330]  ? __zone_watermark_ok+0x92/0x240
[  548.623336]  ? get_page_from_freelist+0x1c3/0x1d90
[  548.623347]  ? _raw_spin_lock_irqsave+0x2a/0x60
[  548.623353]  ? warn_alloc+0x250/0x250
[  548.623358]  ? save_stack+0x46/0xd0
[  548.623361]  ? kasan_kmalloc+0xad/0xe0
[  548.623366]  ? __isolate_free_page+0x2a0/0x2a0
[  548.623370]  ? mount_fs+0x60/0x1a0
[  548.623374]  ? vfs_kern_mount+0x6b/0x1a0
[  548.623378]  ? do_mount+0x34a/0x18c0
[  548.623383]  ? ksys_mount+0x83/0xd0
[  548.623387]  ? __x64_sys_mount+0x67/0x80
[  548.623391]  ? do_syscall_64+0x78/0x170
[  548.623396]  ? entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  548.623401]  __alloc_pages_nodemask+0x3c5/0x400
[  548.623407]  ? __alloc_pages_slowpath+0x1420/0x1420
[  548.623412]  ? __mutex_lock_slowpath+0x20/0x20
[  548.623417]  ? kvmalloc_node+0x31/0x80
[  548.623424]  alloc_pages_current+0x75/0x110
[  548.623436]  kmalloc_order+0x24/0x60
[  548.623442]  kmalloc_order_trace+0x24/0xb0
[  548.623448]  __kmalloc_track_caller+0x207/0x220
[  548.623455]  ? f2fs_build_node_manager+0x399/0xbb0
[  548.623460]  kmemdup+0x20/0x50
[  548.623465]  f2fs_build_node_manager+0x399/0xbb0
[  548.623470]  f2fs_fill_super+0x195e/0x2b40
[  548.623477]  ? f2fs_commit_super+0x1b0/0x1b0
[  548.623481]  ? set_blocksize+0x90/0x140
[  548.623486]  mount_bdev+0x1c5/0x210
[  548.623489]  ? f2fs_commit_super+0x1b0/0x1b0
[  548.623495]  f2fs_mount+0x15/0x20
[  548.623498]  mount_fs+0x60/0x1a0
[  548.623503]  ? alloc_vfsmnt+0x309/0x360
[  548.623508]  vfs_kern_mount+0x6b/0x1a0
[  548.623513]  do_mount+0x34a/0x18c0
[  548.623518]  ? lockref_put_or_lock+0xcf/0x160
[  548.623523]  ? copy_mount_string+0x20/0x20
[  548.623528]  ? memcg_kmem_put_cache+0x1b/0xa0
[  548.623533]  ? kasan_check_write+0x14/0x20
[  548.623537]  ? _copy_from_user+0x6a/0x90
[  548.623542]  ? memdup_user+0x42/0x60
[  548.623547]  ksys_mount+0x83/0xd0
[  548.623552]  __x64_sys_mount+0x67/0x80
[  548.623557]  do_syscall_64+0x78/0x170
[  548.623562]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  548.623566] RIP: 0033:0x7f76fc331b9a
[  548.623567] Code: 48 8b 0d 01 c3 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f 05 &lt;48&gt; 3d 01 f0 ff ff 73 01 c3 48 8b 0d ce c2 2b 00 f7 d8 64 89 01 48
[  548.623632] RSP: 002b:00007ffd4f0a0e48 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
[  548.623636] RAX: ffffffffffffffda RBX: 000000000146c030 RCX: 00007f76fc331b9a
[  548.623639] RDX: 000000000146c210 RSI: 000000000146df30 RDI: 0000000001474ec0
[  548.623641] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000013
[  548.623643] R10: 00000000c0ed0000 R11: 0000000000000206 R12: 0000000001474ec0
[  548.623646] R13: 000000000146c210 R14: 0000000000000000 R15: 0000000000000003
[  548.623650] ---[ end trace 4ce02f25ff7d3df5 ]---
[  548.623656] F2FS-fs (loop0): Failed to initialize F2FS node manager
[  548.627936] F2FS-fs (loop0): Invalid log blocks per segment (8201)

[  548.627940] F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
[  548.635835] F2FS-fs (loop0): Failed to initialize F2FS node manager

- Location
https://elixir.bootlin.com/linux/v4.18-rc1/source/fs/f2fs/segment.c#L3578

	sit_i-&gt;sit_bitmap = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL);

Buffer overrun happens when doing memcpy. I suspect there is missing (inconsistent) checks on bitmap_size.

Reported by Wen Xu (wen.xu@gatech.edu) from SSLab, Gatech.

Reported-by: Wen Xu &lt;wen.xu@gatech.edu&gt;
Signed-off-by: Chao Yu &lt;yuchao0@huawei.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>f2fs: sanity check checkpoint segno and blkoff</title>
<updated>2017-08-11T16:30:14Z</updated>
<author>
<name>Jin Qian</name>
</author>
<published>2017-05-15T17:45:08Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=64133595b549c1036ffe8598f4c53aa355d9e3f1'/>
<id>urn:sha1:64133595b549c1036ffe8598f4c53aa355d9e3f1</id>
<content type='text'>
commit 15d3042a937c13f5d9244241c7a9c8416ff6e82a upstream.

Make sure segno and blkoff read from raw image are valid.

Cc: stable@vger.kernel.org
Signed-off-by: Jin Qian &lt;jinqian@google.com&gt;
[Jaegeuk Kim: adjust minor coding style]
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
[AmitP: Found in Android Security bulletin for Aug'17, fixes CVE-2017-10663]
Signed-off-by: Amit Pundir &lt;amit.pundir@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>f2fs: sanity check segment count</title>
<updated>2017-05-15T07:19:09Z</updated>
<author>
<name>Jin Qian</name>
</author>
<published>2017-04-25T23:28:48Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=27f411c7ee241d194cd5fd3271d83089d70b2c20'/>
<id>urn:sha1:27f411c7ee241d194cd5fd3271d83089d70b2c20</id>
<content type='text'>
commit b9dd46188edc2f0d1f37328637860bb65a771124 upstream.

F2FS uses 4 bytes to represent block address. As a result, supported
size of disk is 16 TB and it equals to 16 * 1024 * 1024 / 2 segments.

Signed-off-by: Jin Qian &lt;jinqian@google.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>f2fs: do more integrity verification for superblock</title>
<updated>2017-05-08T05:44:07Z</updated>
<author>
<name>Chao Yu</name>
</author>
<published>2015-12-15T01:58:18Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=010336c795e15f358c5bd7054175833ee0203121'/>
<id>urn:sha1:010336c795e15f358c5bd7054175833ee0203121</id>
<content type='text'>
commit 9a59b62fd88196844cee5fff851bee2cfd7afb6e upstream.

Do more sanity check for superblock during -&gt;mount.

Signed-off-by: Chao Yu &lt;chao2.yu@samsung.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>f2fs: support atomic writes</title>
<updated>2014-10-07T00:39:50Z</updated>
<author>
<name>Jaegeuk Kim</name>
</author>
<published>2014-10-07T00:39:50Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=88b88a66797159949cec32eaab12b4968f6fae2d'/>
<id>urn:sha1:88b88a66797159949cec32eaab12b4968f6fae2d</id>
<content type='text'>
This patch introduces a very limited functionality for atomic write support.
In order to support atomic write, this patch adds two ioctls:
 o F2FS_IOC_START_ATOMIC_WRITE
 o F2FS_IOC_COMMIT_ATOMIC_WRITE

The database engine should be aware of the following sequence.
1. open
 -&gt; ioctl(F2FS_IOC_START_ATOMIC_WRITE);
2. writes
  : all the written data will be treated as atomic pages.
3. commit
 -&gt; ioctl(F2FS_IOC_COMMIT_ATOMIC_WRITE);
  : this flushes all the data blocks to the disk, which will be shown all or
  nothing by f2fs recovery procedure.
4. repeat to #2.

The IO pattens should be:

  ,- START_ATOMIC_WRITE                  ,- COMMIT_ATOMIC_WRITE
 CP | D D D D D D | FSYNC | D D D D | FSYNC ...
                      `- COMMIT_ATOMIC_WRITE

Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
</entry>
<entry>
<title>f2fs: introduce FITRIM in f2fs_ioctl</title>
<updated>2014-09-30T22:06:09Z</updated>
<author>
<name>Jaegeuk Kim</name>
</author>
<published>2014-09-21T05:06:39Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=4b2fecc84655055a6a1fe9151786992ac04b56ce'/>
<id>urn:sha1:4b2fecc84655055a6a1fe9151786992ac04b56ce</id>
<content type='text'>
This patch introduces FITRIM in f2fs_ioctl.
In this case, f2fs will issue small discards and prefree discards as many as
possible for the given area.

Reviewed-by: Chao Yu &lt;chao2.yu@samsung.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
</entry>
<entry>
<title>f2fs: introduce cp_control structure</title>
<updated>2014-09-30T22:01:28Z</updated>
<author>
<name>Jaegeuk Kim</name>
</author>
<published>2014-09-21T04:57:51Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=75ab4cb8301adb3a02a96c5c03c837ed941f1bc5'/>
<id>urn:sha1:75ab4cb8301adb3a02a96c5c03c837ed941f1bc5</id>
<content type='text'>
This patch add a new data structure to control checkpoint parameters.
Currently, it presents the reason of checkpoint such as is_umount and normal
sync.

Reviewed-by: Chao Yu &lt;chao2.yu@samsung.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
</entry>
<entry>
<title>f2fs: fix to clean previous mount option when remount_fs</title>
<updated>2014-09-23T18:10:22Z</updated>
<author>
<name>Chao Yu</name>
</author>
<published>2014-09-15T10:04:44Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=26666c8a4366debae30ae37d0688b2bec92d196a'/>
<id>urn:sha1:26666c8a4366debae30ae37d0688b2bec92d196a</id>
<content type='text'>
In manual of mount, we descript remount as below:

"mount -o remount,rw /dev/foo /dir
After  this call all old mount options are replaced and arbitrary stuff from
fstab is ignored, except the loop= option which is internally generated and
maintained by the mount command."

Previously f2fs do not clear up old mount options when remount_fs, so we have no
chance of disabling previous option (e.g. flush_merge). Fix it.

Signed-off-by: Chao Yu &lt;chao2.yu@samsung.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
</entry>
<entry>
<title>f2fs: support large sector size</title>
<updated>2014-09-23T18:10:20Z</updated>
<author>
<name>Chao Yu</name>
</author>
<published>2014-09-15T10:01:10Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=55cf9cb63f0e5439f208d78ed944de9a8df65011'/>
<id>urn:sha1:55cf9cb63f0e5439f208d78ed944de9a8df65011</id>
<content type='text'>
Block size in f2fs is 4096 bytes, so theoretically, f2fs can support 4096 bytes
sector device at maximum. But now f2fs only support 512 bytes size sector, so
block device such as zRAM which uses page cache as its block storage space will
not be mounted successfully as mismatch between sector size of zRAM and sector
size of f2fs supported.

In this patch we support large sector size in f2fs, so block device with sector
size of 512/1024/2048/4096 bytes can be supported in f2fs.

Signed-off-by: Chao Yu &lt;chao2.yu@samsung.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
</entry>
<entry>
<title>f2fs: give an option to enable in-place-updates during fsync to users</title>
<updated>2014-09-16T11:10:44Z</updated>
<author>
<name>Jaegeuk Kim</name>
</author>
<published>2014-09-10T23:53:02Z</published>
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If user wrote F2FS_IPU_FSYNC:4 in /sys/fs/f2fs/ipu_policy, f2fs_sync_file
only starts to try in-place-updates.
And, if the number of dirty pages is over /sys/fs/f2fs/min_fsync_blocks, it
keeps out-of-order manner. Otherwise, it triggers in-place-updates.

This may be used by storage showing very high random write performance.

For example, it can be used when,

Seq. writes (Data) + wait + Seq. writes (Node)

is pretty much slower than,

Rand. writes (Data)

Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
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