<feed xmlns='http://www.w3.org/2005/Atom'>
<title>xavi/android_kernel_m2note/fs/proc, branch ng-7.1.2</title>
<subtitle>Unnamed repository; edit this file 'description' to name the repository.
</subtitle>
<id>https://gitea.privatedns.org/xavi/android_kernel_m2note/atom?h=ng-7.1.2</id>
<link rel='self' href='https://gitea.privatedns.org/xavi/android_kernel_m2note/atom?h=ng-7.1.2'/>
<link rel='alternate' type='text/html' href='https://gitea.privatedns.org/xavi/android_kernel_m2note/'/>
<updated>2019-07-08T11:36:43+00:00</updated>
<entry>
<title>fs/proc/proc_sysctl.c: fix NULL pointer dereference in put_links</title>
<updated>2019-07-08T11:36:43+00:00</updated>
<author>
<name>YueHaibing</name>
<email>yuehaibing@huawei.com</email>
</author>
<published>2019-03-29T03:44:40+00:00</published>
<link rel='alternate' type='text/html' href='https://gitea.privatedns.org/xavi/android_kernel_m2note/commit/?id=6833895d9a477f3b438f2f7b4e1ef982e7b06ad3'/>
<id>urn:sha1:6833895d9a477f3b438f2f7b4e1ef982e7b06ad3</id>
<content type='text'>
commit 23da9588037ecdd4901db76a5b79a42b529c4ec3 upstream.

Syzkaller reports:

kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN PTI
CPU: 1 PID: 5373 Comm: syz-executor.0 Not tainted 5.0.0-rc8+ #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
RIP: 0010:put_links+0x101/0x440 fs/proc/proc_sysctl.c:1599
Code: 00 0f 85 3a 03 00 00 48 8b 43 38 48 89 44 24 20 48 83 c0 38 48 89 c2 48 89 44 24 28 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 &lt;80&gt; 3c 02 00 0f 85 fe 02 00 00 48 8b 74 24 20 48 c7 c7 60 2a 9d 91
RSP: 0018:ffff8881d828f238 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8881e01b1140 RCX: ffffffff8ee98267
RDX: 0000000000000007 RSI: ffffc90001479000 RDI: ffff8881e01b1178
RBP: dffffc0000000000 R08: ffffed103ee27259 R09: ffffed103ee27259
R10: 0000000000000001 R11: ffffed103ee27258 R12: fffffffffffffff4
R13: 0000000000000006 R14: ffff8881f59838c0 R15: dffffc0000000000
FS:  00007f072254f700(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff8b286668 CR3: 00000001f0542002 CR4: 00000000007606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 drop_sysctl_table+0x152/0x9f0 fs/proc/proc_sysctl.c:1629
 get_subdir fs/proc/proc_sysctl.c:1022 [inline]
 __register_sysctl_table+0xd65/0x1090 fs/proc/proc_sysctl.c:1335
 br_netfilter_init+0xbc/0x1000 [br_netfilter]
 do_one_initcall+0xfa/0x5ca init/main.c:887
 do_init_module+0x204/0x5f6 kernel/module.c:3460
 load_module+0x66b2/0x8570 kernel/module.c:3808
 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x462e99
Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 &lt;48&gt; 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f072254ec58 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
RAX: ffffffffffffffda RBX: 000000000073bf00 RCX: 0000000000462e99
RDX: 0000000000000000 RSI: 0000000020000280 RDI: 0000000000000003
RBP: 00007f072254ec70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f072254f6bc
R13: 00000000004bcefa R14: 00000000006f6fb0 R15: 0000000000000004
Modules linked in: br_netfilter(+) dvb_usb_dibusb_mc_common dib3000mc dibx000_common dvb_usb_dibusb_common dvb_usb_dw2102 dvb_usb classmate_laptop palmas_regulator cn videobuf2_v4l2 v4l2_common snd_soc_bd28623 mptbase snd_usb_usx2y snd_usbmidi_lib snd_rawmidi wmi libnvdimm lockd sunrpc grace rc_kworld_pc150u rc_core rtc_da9063 sha1_ssse3 i2c_cros_ec_tunnel adxl34x_spi adxl34x nfnetlink lib80211 i5500_temp dvb_as102 dvb_core videobuf2_common videodev media videobuf2_vmalloc videobuf2_memops udc_core lnbp22 leds_lp3952 hid_roccat_ryos s1d13xxxfb mtd vport_geneve openvswitch nf_conncount nf_nat_ipv6 nsh geneve udp_tunnel ip6_udp_tunnel snd_soc_mt6351 sis_agp phylink snd_soc_adau1761_spi snd_soc_adau1761 snd_soc_adau17x1 snd_soc_core snd_pcm_dmaengine ac97_bus snd_compress snd_soc_adau_utils snd_soc_sigmadsp_regmap snd_soc_sigmadsp raid_class hid_roccat_konepure hid_roccat_common hid_roccat c2port_duramar2150 core mdio_bcm_unimac iptable_security iptable_raw iptable_mangle
 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_filter bpfilter ip6_vti ip_vti ip_gre ipip sit tunnel4 ip_tunnel hsr veth netdevsim devlink vxcan batman_adv cfg80211 rfkill chnl_net caif nlmon dummy team bonding vcan bridge stp llc ip6_gre gre ip6_tunnel tunnel6 tun crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel joydev mousedev ide_pci_generic piix aesni_intel aes_x86_64 ide_core crypto_simd atkbd cryptd glue_helper serio_raw ata_generic pata_acpi i2c_piix4 floppy sch_fq_codel ip_tables x_tables ipv6 [last unloaded: lm73]
Dumping ftrace buffer:
   (ftrace buffer empty)
---[ end trace 770020de38961fd0 ]---

A new dir entry can be created in get_subdir and its 'header-&gt;parent' is
set to NULL.  Only after insert_header success, it will be set to 'dir',
otherwise 'header-&gt;parent' is set to NULL and drop_sysctl_table is called.
However in err handling path of get_subdir, drop_sysctl_table also be
called on 'new-&gt;header' regardless its value of parent pointer.  Then
put_links is called, which triggers NULL-ptr deref when access member of
header-&gt;parent.

In fact we have multiple error paths which call drop_sysctl_table() there,
upon failure on insert_links() we also call drop_sysctl_table().And even
in the successful case on __register_sysctl_table() we still always call
drop_sysctl_table().This patch fix it.

Change-Id: I0a1a1bf1c87fd96efdd06b3c2b058ded227bd919
Link: http://lkml.kernel.org/r/20190314085527.13244-1-yuehaibing@huawei.com
Fixes: 0e47c99d7fe25 ("sysctl: Replace root_list with links between sysctl_table_sets")
Signed-off-by: YueHaibing &lt;yuehaibing@huawei.com&gt;
Reported-by: Hulk Robot &lt;hulkci@huawei.com&gt;
Acked-by: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Cc: Alexei Starovoitov &lt;ast@kernel.org&gt;
Cc: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;    [3.4+]
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>Revert "GCC: Fix up for gcc 5+"</title>
<updated>2018-11-29T23:02:49+00:00</updated>
<author>
<name>Moyster</name>
<email>oysterized@gmail.com</email>
</author>
<published>2018-11-29T22:59:26+00:00</published>
<link rel='alternate' type='text/html' href='https://gitea.privatedns.org/xavi/android_kernel_m2note/commit/?id=be2a1194e40a49e08b28bc415e5126b0a99e1194'/>
<id>urn:sha1:be2a1194e40a49e08b28bc415e5126b0a99e1194</id>
<content type='text'>
This reverts commit ff505baaf412985af758d5820cd620ed9f1a7e05.
</content>
</entry>
<entry>
<title>Replace &lt;asm/uaccess.h&gt; with &lt;linux/uaccess.h&gt; globally</title>
<updated>2018-11-29T16:49:05+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-12-24T19:46:01+00:00</published>
<link rel='alternate' type='text/html' href='https://gitea.privatedns.org/xavi/android_kernel_m2note/commit/?id=8588b01909e0145e5e84f5fe0a5353bd194f205c'/>
<id>urn:sha1:8588b01909e0145e5e84f5fe0a5353bd194f205c</id>
<content type='text'>
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*&lt;asm/uaccess.h&gt;'
  sed -i -e "s!$PATT!#include &lt;linux/uaccess.h&gt;!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Moyster &lt;oysterized@gmail.com&gt;
</content>
</entry>
<entry>
<title>GCC: Fix up for gcc 5+</title>
<updated>2018-11-29T11:38:19+00:00</updated>
<author>
<name>mydongistiny</name>
<email>jaysonedson@gmail.com</email>
</author>
<published>2015-11-24T01:01:42+00:00</published>
<link rel='alternate' type='text/html' href='https://gitea.privatedns.org/xavi/android_kernel_m2note/commit/?id=ff505baaf412985af758d5820cd620ed9f1a7e05'/>
<id>urn:sha1:ff505baaf412985af758d5820cd620ed9f1a7e05</id>
<content type='text'>
Signed-off-by: mydongistiny &lt;jaysonedson@gmail.com&gt;
Signed-off-by: Mister Oyster &lt;oysterized@gmail.com&gt;
</content>
</entry>
<entry>
<title>fs: proc: task_mmu: fix proc_mem_open creds for fs access checks</title>
<updated>2017-09-23T16:29:49+00:00</updated>
<author>
<name>Mister Oyster</name>
<email>oysterized@gmail.com</email>
</author>
<published>2017-09-23T16:27:49+00:00</published>
<link rel='alternate' type='text/html' href='https://gitea.privatedns.org/xavi/android_kernel_m2note/commit/?id=c7f42f5bcd6ae56cb5657a20aaf8f4a50565b4d3'/>
<id>urn:sha1:c7f42f5bcd6ae56cb5657a20aaf8f4a50565b4d3</id>
<content type='text'>
Should fix :
[ 2201.337557]&lt;0&gt; (0)[672:android.bg]WARNING: at
../../../../../../kernel/meizu/m2note/kernel/ptrace.c:239
__ptrace_may_access+0x164/0x178()
[ 2201.337568]&lt;0&gt; (0)[672:android.bg]denying ptrace access check without
PTRACE_MODE_*CREDS
[ 2201.337583]&lt;0&gt; (0)[672:android.bg]CPU: 0 PID: 672 Comm: android.bg
Tainted: G        W    3.10.107-NOyster #1
[ 2201.337593]&lt;0&gt; (0)[672:android.bg]Call trace:
[ 2201.337609]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc000089558&gt;]
dump_backtrace+0x0/0x148
[ 2201.337625]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc0000896b4&gt;]
show_stack+0x14/0x1c
[ 2201.337642]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc0009e88d4&gt;]
dump_stack+0x20/0x28
[ 2201.337657]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc00009b6cc&gt;]
warn_slowpath_fmt+0xb0/0x134
[ 2201.337673]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc0000ab378&gt;]
__ptrace_may_access+0x164/0x178
[ 2201.337687]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc0000ab8c0&gt;]
ptrace_may_access+0x2c/0x4c
[ 2201.337704]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc000098d48&gt;]
mm_access+0x98/0xe0
[ 2201.337722]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc00020e788&gt;]
proc_mem_open+0x2c/0xa0
[ 2201.337739]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc00020a79c&gt;]
pid_smaps_open+0x48/0x88
[ 2201.337756]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc0001a0c54&gt;]
do_dentry_open+0x178/0x268
[ 2201.337772]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc0001a1e30&gt;]
finish_open+0x30/0x5c
[ 2201.337787]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc0001b12c0&gt;]
do_last.isra.29+0x45c/0xcbc
[ 2201.337802]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc0001b1bd8&gt;]
path_openat.isra.30+0xb8/0x494
[ 2201.337817]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc0001b2028&gt;]
do_filp_open+0x40/0xb4
[ 2201.337834]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc0001a22fc&gt;]
do_sys_open+0x118/0x1f0
[ 2201.337851]&lt;0&gt; (0)[672:android.bg][&lt;ffffffc0001a240c&gt;]
SyS_openat+0x10/0x18
[ 2201.337861]&lt;0&gt; (0)[672:android.bg]---[ end trace e7bf4b0b0cb5766d
]---

Signed-off-by: Mister Oyster &lt;oysterized@gmail.com&gt;
</content>
</entry>
<entry>
<title>seq_file: remove "%n" usage from seq_file users</title>
<updated>2017-09-23T13:02:44+00:00</updated>
<author>
<name>Tetsuo Handa</name>
<email>penguin-kernel@I-love.SAKURA.ne.jp</email>
</author>
<published>2013-11-14T22:31:57+00:00</published>
<link rel='alternate' type='text/html' href='https://gitea.privatedns.org/xavi/android_kernel_m2note/commit/?id=e5d7201d83b72fb67d5fd7dc7b0e003106026973'/>
<id>urn:sha1:e5d7201d83b72fb67d5fd7dc7b0e003106026973</id>
<content type='text'>
All seq_printf() users are using "%n" for calculating padding size,
convert them to use seq_setwidth() / seq_pad() pair.

Signed-off-by: Tetsuo Handa &lt;penguin-kernel@I-love.SAKURA.ne.jp&gt;
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Joe Perches &lt;joe@perches.com&gt;
Cc: David Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Git-commit: 652586df95e5d76b37d07a11839126dcfede1621
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[davidb@codeaurora.org: Resolve merge conflicts with ipv4/6 ping
 changes in upstream]
CRs-fixed: 665291
Change-Id: Ia0416c9dbe3d80ff35f24f9c93c3543d1200a327
Signed-off-by: David Brown &lt;davidb@codeaurora.org&gt;
</content>
</entry>
<entry>
<title>mm: larger stack guard gap, between vmas</title>
<updated>2017-07-04T10:11:29+00:00</updated>
<author>
<name>Hugh Dickins</name>
<email>hughd@google.com</email>
</author>
<published>2017-06-19T11:03:24+00:00</published>
<link rel='alternate' type='text/html' href='https://gitea.privatedns.org/xavi/android_kernel_m2note/commit/?id=005510a4492897b8459a7678191bd9ea39335bee'/>
<id>urn:sha1:005510a4492897b8459a7678191bd9ea39335bee</id>
<content type='text'>
commit 1be7107fbe18eed3e319a6c3e83c78254b693acb upstream.

Stack guard page is a useful feature to reduce a risk of stack smashing
into a different mapping. We have been using a single page gap which
is sufficient to prevent having stack adjacent to a different mapping.
But this seems to be insufficient in the light of the stack usage in
userspace. E.g. glibc uses as large as 64kB alloca() in many commonly
used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX]
which is 256kB or stack strings with MAX_ARG_STRLEN.

This will become especially dangerous for suid binaries and the default
no limit for the stack size limit because those applications can be
tricked to consume a large portion of the stack and a single glibc call
could jump over the guard page. These attacks are not theoretical,
unfortunatelly.

Make those attacks less probable by increasing the stack guard gap
to 1MB (on systems with 4k pages; but make it depend on the page size
because systems with larger base pages might cap stack allocations in
the PAGE_SIZE units) which should cover larger alloca() and VLA stack
allocations. It is obviously not a full fix because the problem is
somehow inherent, but it should reduce attack space a lot.

One could argue that the gap size should be configurable from userspace,
but that can be done later when somebody finds that the new 1MB is wrong
for some special case applications.  For now, add a kernel command line
option (stack_guard_gap) to specify the stack gap size (in page units).

Implementation wise, first delete all the old code for stack guard page:
because although we could get away with accounting one extra page in a
stack vma, accounting a larger gap can break userspace - case in point,
a program run with "ulimit -S -v 20000" failed when the 1MB gap was
counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK
and strict non-overcommit mode.

Instead of keeping gap inside the stack vma, maintain the stack guard
gap as a gap between vmas: using vm_start_gap() in place of vm_start
(or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few
places which need to respect the gap - mainly arch_get_unmapped_area(),
and and the vma tree's subtree_gap support for that.

Original-patch-by: Oleg Nesterov &lt;oleg@redhat.com&gt;
Original-patch-by: Michal Hocko &lt;mhocko@suse.com&gt;
Signed-off-by: Hugh Dickins &lt;hughd@google.com&gt;
[wt: backport to 4.11: adjust context]
[wt: backport to 4.9: adjust context ; kernel doc was not in admin-guide]
[wt: backport to 4.4: adjust context ; drop ppc hugetlb_radix changes]
[wt: backport to 3.18: adjust context ; no FOLL_POPULATE ;
     s390 uses generic arch_get_unmapped_area()]
[wt: backport to 3.16: adjust context]
[wt: backport to 3.10: adjust context ; code logic in PARISC's
     arch_get_unmapped_area() wasn't found ; code inserted into
     expand_upwards() and expand_downwards() runs under anon_vma lock;
     changes for gup.c:faultin_page go to memory.c:__get_user_pages();
     included Hugh Dickins' fixes]
Signed-off-by: Willy Tarreau &lt;w@1wt.eu&gt;
</content>
</entry>
<entry>
<title>uksm: remove Mtk aksm &amp; uksm (because its fugly)</title>
<updated>2017-07-04T10:11:29+00:00</updated>
<author>
<name>Mister Oyster</name>
<email>oysterized@gmail.com</email>
</author>
<published>2017-07-03T10:14:46+00:00</published>
<link rel='alternate' type='text/html' href='https://gitea.privatedns.org/xavi/android_kernel_m2note/commit/?id=af79a782f868c860793e76ed5ec1ae5bb4af4187'/>
<id>urn:sha1:af79a782f868c860793e76ed5ec1ae5bb4af4187</id>
<content type='text'>
Revert "KSM: mediatek: implement Adaptive KSM"
Revert "mm: uksm: fix maybe-uninitialized warning"
Revert "UKSM: Add Governors for Higher CPU usage (HighCPU) for more merging, and low cpu usage (Battery) for less battery drain"
Revert "uksm: use deferrable timer"
Revert "mm: limit UKSM sleep time instead of failing"
Revert "uksm: Fix warning"
Revert "uksm: clean up and remove some (no)inlines"
Revert "uksm: modify ema logic and tidy up"
Revert "uksm: enhancements and cleanups"
Revert "uksm: squashed fixups"
Revert "UKSM: cast variable as const"
Revert "UKSM: remove U64_MAX definition"
Revert "add uksm 0.1.2.3 for v3.10 .ge.46.patch"
</content>
</entry>
<entry>
<title>UPSTREAM: proc: actually make proc_fd_permission() thread-friendly</title>
<updated>2017-05-24T00:22:22+00:00</updated>
<author>
<name>Oleg Nesterov</name>
<email>oleg@redhat.com</email>
</author>
<published>2015-11-07T00:30:06+00:00</published>
<link rel='alternate' type='text/html' href='https://gitea.privatedns.org/xavi/android_kernel_m2note/commit/?id=c1a3cb6fad12aca8661ec649de9fec1ee5e6c104'/>
<id>urn:sha1:c1a3cb6fad12aca8661ec649de9fec1ee5e6c104</id>
<content type='text'>
(cherry pick from commit 54708d2858e79a2bdda10bf8a20c80eb96c20613)

The commit 96d0df79f264 ("proc: make proc_fd_permission() thread-friendly")
fixed the access to /proc/self/fd from sub-threads, but introduced another
problem: a sub-thread can't access /proc/&lt;tid&gt;/fd/ or /proc/thread-self/fd
if generic_permission() fails.

Change proc_fd_permission() to check same_thread_group(pid_task(), current).

Fixes: 96d0df79f264 ("proc: make proc_fd_permission() thread-friendly")
Reported-by: "Jin, Yihua" &lt;yihua.jin@intel.com&gt;
Signed-off-by: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Bug: 26016905
Change-Id: I1894c78d0b13f0bde8cde84bd142ba67590dc0f1
</content>
</entry>
<entry>
<title>UPSTREAM: proc: make proc_fd_permission() thread-friendly</title>
<updated>2017-05-24T00:22:21+00:00</updated>
<author>
<name>Oleg Nesterov</name>
<email>oleg@redhat.com</email>
</author>
<published>2013-09-11T21:24:37+00:00</published>
<link rel='alternate' type='text/html' href='https://gitea.privatedns.org/xavi/android_kernel_m2note/commit/?id=46dd3cad9b928734e459d5e7c625ab8727b4a39d'/>
<id>urn:sha1:46dd3cad9b928734e459d5e7c625ab8727b4a39d</id>
<content type='text'>
(cherry pick from commit 96d0df79f2644fc823f26c06491e182d87a90c2a)

proc_fd_permission() says "process can still access /proc/self/fd after it
has executed a setuid()", but the "task_pid() = proc_pid() check only
helps if the task is group leader, /proc/self points to
/proc/&lt;leader-pid&gt;.

Change this check to use task_tgid() so that the whole thread group can
access its /proc/self/fd or /proc/&lt;tid-of-sub-thread&gt;/fd.

Notes:
	- CLONE_THREAD does not require CLONE_FILES so task-&gt;files
	  can differ, but I don't think this can lead to any security
	  problem. And this matches same_thread_group() in
	  __ptrace_may_access().

	- /proc/self should probably point to /proc/&lt;thread-tid&gt;, but
	  it is too late to change the rules. Perhaps it makes sense
	  to add /proc/thread though.

Test-case:

	void *tfunc(void *arg)
	{
		assert(opendir("/proc/self/fd"));
		return NULL;
	}

	int main(void)
	{
		pthread_t t;
		pthread_create(&amp;t, NULL, tfunc, NULL);
		pthread_join(t, NULL);
		return 0;
	}

fails if, say, this executable is not readable and suid_dumpable = 0.

Signed-off-by: Oleg Nesterov &lt;oleg@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Bug: 26016905
Change-Id: Ifdd6403a8fccd073122e89d3547c13ccc08f0dce
Signed-off-by: Joe Maples &lt;joe@frap129.org&gt;

Conflicts:
	fs/proc/fd.c
</content>
</entry>
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