<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/ipc/mqueue.c, branch v5.3.11</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.3.11</id>
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<updated>2019-07-19T17:42:02Z</updated>
<entry>
<title>Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs</title>
<updated>2019-07-19T17:42:02Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-07-19T17:42:02Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=933a90bf4f3505f8ec83bda21a3c7d70d7c2b426'/>
<id>urn:sha1:933a90bf4f3505f8ec83bda21a3c7d70d7c2b426</id>
<content type='text'>
Pull vfs mount updates from Al Viro:
 "The first part of mount updates.

  Convert filesystems to use the new mount API"

* 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  mnt_init(): call shmem_init() unconditionally
  constify ksys_mount() string arguments
  don't bother with registering rootfs
  init_rootfs(): don't bother with init_ramfs_fs()
  vfs: Convert smackfs to use the new mount API
  vfs: Convert selinuxfs to use the new mount API
  vfs: Convert securityfs to use the new mount API
  vfs: Convert apparmorfs to use the new mount API
  vfs: Convert openpromfs to use the new mount API
  vfs: Convert xenfs to use the new mount API
  vfs: Convert gadgetfs to use the new mount API
  vfs: Convert oprofilefs to use the new mount API
  vfs: Convert ibmasmfs to use the new mount API
  vfs: Convert qib_fs/ipathfs to use the new mount API
  vfs: Convert efivarfs to use the new mount API
  vfs: Convert configfs to use the new mount API
  vfs: Convert binfmt_misc to use the new mount API
  convenience helper: get_tree_single()
  convenience helper get_tree_nodev()
  vfs: Kill sget_userns()
  ...
</content>
</entry>
<entry>
<title>ipc/mqueue.c: only perform resource calculation if user valid</title>
<updated>2019-07-17T02:23:24Z</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2019-07-16T23:30:21Z</published>
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<id>urn:sha1:a318f12ed8843cfac53198390c74a565c632f417</id>
<content type='text'>
Andreas Christoforou reported:

  UBSAN: Undefined behaviour in ipc/mqueue.c:414:49 signed integer overflow:
  9 * 2305843009213693951 cannot be represented in type 'long int'
  ...
  Call Trace:
    mqueue_evict_inode+0x8e7/0xa10 ipc/mqueue.c:414
    evict+0x472/0x8c0 fs/inode.c:558
    iput_final fs/inode.c:1547 [inline]
    iput+0x51d/0x8c0 fs/inode.c:1573
    mqueue_get_inode+0x8eb/0x1070 ipc/mqueue.c:320
    mqueue_create_attr+0x198/0x440 ipc/mqueue.c:459
    vfs_mkobj+0x39e/0x580 fs/namei.c:2892
    prepare_open ipc/mqueue.c:731 [inline]
    do_mq_open+0x6da/0x8e0 ipc/mqueue.c:771

Which could be triggered by:

        struct mq_attr attr = {
                .mq_flags = 0,
                .mq_maxmsg = 9,
                .mq_msgsize = 0x1fffffffffffffff,
                .mq_curmsgs = 0,
        };

        if (mq_open("/testing", 0x40, 3, &amp;attr) == (mqd_t) -1)
                perror("mq_open");

mqueue_get_inode() was correctly rejecting the giant mq_msgsize, and
preparing to return -EINVAL.  During the cleanup, it calls
mqueue_evict_inode() which performed resource usage tracking math for
updating "user", before checking if there was a valid "user" at all
(which would indicate that the calculations would be sane).  Instead,
delay this check to after seeing a valid "user".

The overflow was real, but the results went unused, so while the flaw is
harmless, it's noisy for kernel fuzzers, so just fix it by moving the
calculation under the non-NULL "user" where it actually gets used.

Link: http://lkml.kernel.org/r/201906072207.ECB65450@keescook
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Reported-by: Andreas Christoforou &lt;andreaschristofo@gmail.com&gt;
Acked-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Davidlohr Bueso &lt;dave@stgolabs.net&gt;
Cc: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>mqueue: set -&gt;user_ns before -&gt;get_tree()</title>
<updated>2019-05-25T22:00:00Z</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2019-05-12T21:46:05Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=709a643da8b8c5fc823e1870d8227ca0eeb51311'/>
<id>urn:sha1:709a643da8b8c5fc823e1870d8227ca0eeb51311</id>
<content type='text'>
... so that we could lift the capability checks into -&gt;get_tree()
caller

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
</entry>
<entry>
<title>ipc/mqueue: optimize msg_get()</title>
<updated>2019-05-15T02:52:52Z</updated>
<author>
<name>Davidlohr Bueso</name>
<email>dave@stgolabs.net</email>
</author>
<published>2019-05-14T22:46:26Z</published>
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<id>urn:sha1:a5091fda4e3c202aeb1728a86d0fcd20fd0f4f5e</id>
<content type='text'>
Our msg priorities became an rbtree as of d6629859b36d ("ipc/mqueue:
improve performance of send/recv").  However, consuming a msg in
msg_get() remains logarithmic (still being better than the case before
of course).  By applying well known techniques to cache pointers we can
have the node with the highest priority in O(1), which is specially nice
for the rt cases.  Furthermore, some callers can call msg_get() in a
loop.

A new msg_tree_erase() helper is also added to encapsulate the tree
removal and node_cache game.  Passes ltp mq testcases.

Link: http://lkml.kernel.org/r/20190321190216.1719-2-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso &lt;dbueso@suse.de&gt;
Cc: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>ipc/mqueue: remove redundant wq task assignment</title>
<updated>2019-05-15T02:52:52Z</updated>
<author>
<name>Davidlohr Bueso</name>
<email>dave@stgolabs.net</email>
</author>
<published>2019-05-14T22:46:23Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=0ecb58210bd9de14df62a614be07428ef10f9469'/>
<id>urn:sha1:0ecb58210bd9de14df62a614be07428ef10f9469</id>
<content type='text'>
We already store the current task fo the new waiter before calling
wq_sleep() in both send and recv paths.  Trivially remove the redundant
assignment.

Link: http://lkml.kernel.org/r/20190321190216.1719-1-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso &lt;dbueso@suse.de&gt;
Cc: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>ipc: prevent lockup on alloc_msg and free_msg</title>
<updated>2019-05-15T02:52:52Z</updated>
<author>
<name>Li Rongqing</name>
<email>lirongqing@baidu.com</email>
</author>
<published>2019-05-14T22:46:20Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=d6a2946a88f524a47cc9b79279667137899db807'/>
<id>urn:sha1:d6a2946a88f524a47cc9b79279667137899db807</id>
<content type='text'>
msgctl10 of ltp triggers the following lockup When CONFIG_KASAN is
enabled on large memory SMP systems, the pages initialization can take a
long time, if msgctl10 requests a huge block memory, and it will block
rcu scheduler, so release cpu actively.

After adding schedule() in free_msg, free_msg can not be called when
holding spinlock, so adding msg to a tmp list, and free it out of
spinlock

  rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
  rcu:     Tasks blocked on level-1 rcu_node (CPUs 16-31): P32505
  rcu:     Tasks blocked on level-1 rcu_node (CPUs 48-63): P34978
  rcu:     (detected by 11, t=35024 jiffies, g=44237529, q=16542267)
  msgctl10        R  running task    21608 32505   2794 0x00000082
  Call Trace:
   preempt_schedule_irq+0x4c/0xb0
   retint_kernel+0x1b/0x2d
  RIP: 0010:__is_insn_slot_addr+0xfb/0x250
  Code: 82 1d 00 48 8b 9b 90 00 00 00 4c 89 f7 49 c1 ee 03 e8 59 83 1d 00 48 b8 00 00 00 00 00 fc ff df 4c 39 eb 48 89 9d 58 ff ff ff &lt;41&gt; c6 04 06 f8 74 66 4c 8d 75 98 4c 89 f1 48 c1 e9 03 48 01 c8 48
  RSP: 0018:ffff88bce041f758 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
  RAX: dffffc0000000000 RBX: ffffffff8471bc50 RCX: ffffffff828a2a57
  RDX: dffffc0000000000 RSI: dffffc0000000000 RDI: ffff88bce041f780
  RBP: ffff88bce041f828 R08: ffffed15f3f4c5b3 R09: ffffed15f3f4c5b3
  R10: 0000000000000001 R11: ffffed15f3f4c5b2 R12: 000000318aee9b73
  R13: ffffffff8471bc50 R14: 1ffff1179c083ef0 R15: 1ffff1179c083eec
   kernel_text_address+0xc1/0x100
   __kernel_text_address+0xe/0x30
   unwind_get_return_address+0x2f/0x50
   __save_stack_trace+0x92/0x100
   create_object+0x380/0x650
   __kmalloc+0x14c/0x2b0
   load_msg+0x38/0x1a0
   do_msgsnd+0x19e/0xcf0
   do_syscall_64+0x117/0x400
   entry_SYSCALL_64_after_hwframe+0x49/0xbe

  rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
  rcu:     Tasks blocked on level-1 rcu_node (CPUs 0-15): P32170
  rcu:     (detected by 14, t=35016 jiffies, g=44237525, q=12423063)
  msgctl10        R  running task    21608 32170  32155 0x00000082
  Call Trace:
   preempt_schedule_irq+0x4c/0xb0
   retint_kernel+0x1b/0x2d
  RIP: 0010:lock_acquire+0x4d/0x340
  Code: 48 81 ec c0 00 00 00 45 89 c6 4d 89 cf 48 8d 6c 24 20 48 89 3c 24 48 8d bb e4 0c 00 00 89 74 24 0c 48 c7 44 24 20 b3 8a b5 41 &lt;48&gt; c1 ed 03 48 c7 44 24 28 b4 25 18 84 48 c7 44 24 30 d0 54 7a 82
  RSP: 0018:ffff88af83417738 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
  RAX: dffffc0000000000 RBX: ffff88bd335f3080 RCX: 0000000000000002
  RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88bd335f3d64
  RBP: ffff88af83417758 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000001 R11: ffffed13f3f745b2 R12: 0000000000000000
  R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000000
   is_bpf_text_address+0x32/0xe0
   kernel_text_address+0xec/0x100
   __kernel_text_address+0xe/0x30
   unwind_get_return_address+0x2f/0x50
   __save_stack_trace+0x92/0x100
   save_stack+0x32/0xb0
   __kasan_slab_free+0x130/0x180
   kfree+0xfa/0x2d0
   free_msg+0x24/0x50
   do_msgrcv+0x508/0xe60
   do_syscall_64+0x117/0x400
   entry_SYSCALL_64_after_hwframe+0x49/0xbe

Davidlohr said:
 "So after releasing the lock, the msg rbtree/list is empty and new
  calls will not see those in the newly populated tmp_msg list, and
  therefore they cannot access the delayed msg freeing pointers, which
  is good. Also the fact that the node_cache is now freed before the
  actual messages seems to be harmless as this is wanted for
  msg_insert() avoiding GFP_ATOMIC allocations, and after releasing the
  info-&gt;lock the thing is freed anyway so it should not change things"

Link: http://lkml.kernel.org/r/1552029161-4957-1-git-send-email-lirongqing@baidu.com
Signed-off-by: Li RongQing &lt;lirongqing@baidu.com&gt;
Signed-off-by: Zhang Yu &lt;zhangyu31@baidu.com&gt;
Reviewed-by: Davidlohr Bueso &lt;dbueso@suse.de&gt;
Cc: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>mqueue: switch to -&gt;free_inode()</title>
<updated>2019-05-02T02:43:26Z</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2019-04-16T02:30:30Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=015d7956183b3943a1e101fa9911e1b5333bdc4b'/>
<id>urn:sha1:015d7956183b3943a1e101fa9911e1b5333bdc4b</id>
<content type='text'>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
</entry>
<entry>
<title>Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs</title>
<updated>2019-03-12T21:08:19Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-03-12T21:08:19Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=7b47a9e7c8f672b6fb0b77fca11a63a8a77f5a91'/>
<id>urn:sha1:7b47a9e7c8f672b6fb0b77fca11a63a8a77f5a91</id>
<content type='text'>
Pull vfs mount infrastructure updates from Al Viro:
 "The rest of core infrastructure; no new syscalls in that pile, but the
  old parts are switched to new infrastructure. At that point
  conversions of individual filesystems can happen independently; some
  are done here (afs, cgroup, procfs, etc.), there's also a large series
  outside of that pile dealing with NFS (quite a bit of option-parsing
  stuff is getting used there - it's one of the most convoluted
  filesystems in terms of mount-related logics), but NFS bits are the
  next cycle fodder.

  It got seriously simplified since the last cycle; documentation is
  probably the weakest bit at the moment - I considered dropping the
  commit introducing Documentation/filesystems/mount_api.txt (cutting
  the size increase by quarter ;-), but decided that it would be better
  to fix it up after -rc1 instead.

  That pile allows to do followup work in independent branches, which
  should make life much easier for the next cycle. fs/super.c size
  increase is unpleasant; there's a followup series that allows to
  shrink it considerably, but I decided to leave that until the next
  cycle"

* 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (41 commits)
  afs: Use fs_context to pass parameters over automount
  afs: Add fs_context support
  vfs: Add some logging to the core users of the fs_context log
  vfs: Implement logging through fs_context
  vfs: Provide documentation for new mount API
  vfs: Remove kern_mount_data()
  hugetlbfs: Convert to fs_context
  cpuset: Use fs_context
  kernfs, sysfs, cgroup, intel_rdt: Support fs_context
  cgroup: store a reference to cgroup_ns into cgroup_fs_context
  cgroup1_get_tree(): separate "get cgroup_root to use" into a separate helper
  cgroup_do_mount(): massage calling conventions
  cgroup: stash cgroup_root reference into cgroup_fs_context
  cgroup2: switch to option-by-option parsing
  cgroup1: switch to option-by-option parsing
  cgroup: take options parsing into -&gt;parse_monolithic()
  cgroup: fold cgroup1_mount() into cgroup1_get_tree()
  cgroup: start switching to fs_context
  ipc: Convert mqueue fs to fs_context
  proc: Add fs_context support to procfs
  ...
</content>
</entry>
<entry>
<title>ipc: Convert mqueue fs to fs_context</title>
<updated>2019-02-28T08:29:29Z</updated>
<author>
<name>David Howells</name>
<email>dhowells@redhat.com</email>
</author>
<published>2018-11-01T23:07:25Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=935c6912b198f60a812b7dada21027b5aac7c461'/>
<id>urn:sha1:935c6912b198f60a812b7dada21027b5aac7c461</id>
<content type='text'>
Convert the mqueue filesystem to use the filesystem context stuff.

Notes:

 (1) The relevant ipc namespace is selected in when the context is
     initialised (and it defaults to the current task's ipc namespace).
     The caller can override this before calling vfs_get_tree().

 (2) Rather than simply calling kern_mount_data(), mq_init_ns() and
     mq_internal_mount() create a context, adjust it and then do the rest
     of the mount procedure.

 (3) The lazy mqueue mounting on creation of a new namespace is retained
     from a previous patch, but the avoidance of sget() if no superblock
     yet exists is reverted and the superblock is again keyed on the
     namespace pointer.

     Yes, there was a performance gain in not searching the superblock
     hash, but it's only paid once per ipc namespace - and only if someone
     uses mqueue within that namespace, so I'm not sure it's worth it,
     especially as calling sget() allows avoidance of recursion.

Signed-off-by: David Howells &lt;dhowells@redhat.com&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
</entry>
<entry>
<title>y2038: syscalls: rename y2038 compat syscalls</title>
<updated>2019-02-06T23:13:27Z</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2019-01-06T23:33:08Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=8dabe7245bbc134f2cfcc12cde75c019dab924cc'/>
<id>urn:sha1:8dabe7245bbc134f2cfcc12cde75c019dab924cc</id>
<content type='text'>
A lot of system calls that pass a time_t somewhere have an implementation
using a COMPAT_SYSCALL_DEFINEx() on 64-bit architectures, and have
been reworked so that this implementation can now be used on 32-bit
architectures as well.

The missing step is to redefine them using the regular SYSCALL_DEFINEx()
to get them out of the compat namespace and make it possible to build them
on 32-bit architectures.

Any system call that ends in 'time' gets a '32' suffix on its name for
that version, while the others get a '_time32' suffix, to distinguish
them from the normal version, which takes a 64-bit time argument in the
future.

In this step, only 64-bit architectures are changed, doing this rename
first lets us avoid touching the 32-bit architectures twice.

Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
</content>
</entry>
</feed>
