1. 27 12月, 2019 40 次提交
    • S
      selftests: Fix test errors related to lib.mk khdr target · de9178c9
      Shuah Khan 提交于
      commit 211929fd upstream.
      
      Commit b2d35fa5 ("selftests: add headers_install to lib.mk") added
      khdr target to run headers_install target from the main Makefile. The
      logic uses KSFT_KHDR_INSTALL and top_srcdir as controls to initialize
      variables and include files to run headers_install from the top level
      Makefile. There are a few problems with this logic.
      
      1. Exposes top_srcdir to all tests
      2. Common logic impacts all tests
      3. Uses KSFT_KHDR_INSTALL, top_srcdir, and khdr in an adhoc way. Tests
         add "khdr" dependency in their Makefiles to TEST_PROGS_EXTENDED in
         some cases, and STATIC_LIBS in other cases. This makes this framework
         confusing to use.
      
      The common logic that runs for all tests even when KSFT_KHDR_INSTALL
      isn't defined by the test. top_srcdir is initialized to a default value
      when test doesn't initialize it. It works for all tests without a sub-dir
      structure and tests with sub-dir structure fail to build.
      
      e.g: make -C sparc64/drivers/ or make -C drivers/dma-buf
      
      ../../lib.mk:20: ../../../../scripts/subarch.include: No such file or directory
      make: *** No rule to make target '../../../../scripts/subarch.include'.  Stop.
      
      There is no reason to require all tests to define top_srcdir and there is
      no need to require tests to add khdr dependency using adhoc changes to
      TEST_* and other variables.
      
      Fix it with a consistent use of KSFT_KHDR_INSTALL and top_srcdir from tests
      that have the dependency on headers_install.
      
      Change common logic to include khdr target define and "all" target with
      dependency on khdr when KSFT_KHDR_INSTALL is defined.
      
      Only tests that have dependency on headers_install have to define just
      the KSFT_KHDR_INSTALL, and top_srcdir variables and there is no need to
      specify khdr dependency in the test Makefiles.
      
      Fixes: b2d35fa5 ("selftests: add headers_install to lib.mk")
      Cc: stable@vger.kernel.org
      Signed-off-by: NShuah Khan <shuah@kernel.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      de9178c9
    • I
      drm/fb-helper: Ignore the value of fb_var_screeninfo.pixclock · d5ffeab2
      Ivan Mironov 提交于
      commit 66a8d5bf upstream.
      
      Strict requirement of pixclock to be zero breaks support of SDL 1.2
      which contains hardcoded table of supported video modes with non-zero
      pixclock values[1].
      
      To better understand which pixclock values are considered valid and how
      driver should handle these values, I briefly examined few existing fbdev
      drivers and documentation in Documentation/fb/. And it looks like there
      are no strict rules on that and actual behaviour varies:
      
      	* some drivers treat (pixclock == 0) as "use defaults" (uvesafb.c);
      	* some treat (pixclock == 0) as invalid value which leads to
      	  -EINVAL (clps711x-fb.c);
      	* some pass converted pixclock value to hardware (uvesafb.c);
      	* some are trying to find nearest value from predefined table
                (vga16fb.c, video_gx.c).
      
      Given this, I believe that it should be safe to just ignore this value if
      changing is not supported. It seems that any portable fbdev application
      which was not written only for one specific device working under one
      specific kernel version should not rely on any particular behaviour of
      pixclock anyway.
      
      However, while enabling SDL1 applications to work out of the box when
      there is no /etc/fb.modes with valid settings, this change affects the
      video mode choosing logic in SDL. Depending on current screen
      resolution, contents of /etc/fb.modes and resolution requested by
      application, this may lead to user-visible difference (not always):
      image will be displayed in a right way, but it will be aligned to the
      left instead of center. There is no "right behaviour" here as well, as
      emulated fbdev, opposing to old fbdev drivers, simply ignores any
      requsts of video mode changes with resolutions smaller than current.
      
      The easiest way to reproduce this problem is to install sdl-sopwith[2],
      remove /etc/fb.modes file if it exists, and then try to run sopwith
      from console without X. At least in Fedora 29, sopwith may be simply
      installed from standard repositories.
      
      [1] SDL 1.2.15 source code, src/video/fbcon/SDL_fbvideo.c, vesa_timings
      [2] http://sdl-sopwith.sourceforge.net/Signed-off-by: NIvan Mironov <mironov.ivan@gmail.com>
      Cc: stable@vger.kernel.org
      Fixes: 79e53945 ("DRM: i915: add mode setting support")
      Fixes: 771fe6b9 ("drm/radeon: introduce kernel modesetting for radeon hardware")
      Fixes: 785b93ef ("drm/kms: move driver specific fb common code to helper functions (v2)")
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      Link: https://patchwork.freedesktop.org/patch/msgid/20190108072353.28078-3-mironov.ivan@gmail.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      d5ffeab2
    • J
      loop: drop caches if offset or block_size are changed · 5aa6c2bd
      Jaegeuk Kim 提交于
      commit 5db470e2 upstream.
      
      If we don't drop caches used in old offset or block_size, we can get old data
      from new offset/block_size, which gives unexpected data to user.
      
      For example, Martijn found a loopback bug in the below scenario.
      1) LOOP_SET_FD loads first two pages on loop file
      2) LOOP_SET_STATUS64 changes the offset on the loop file
      3) mount is failed due to the cached pages having wrong superblock
      
      Cc: Jens Axboe <axboe@kernel.dk>
      Cc: linux-block@vger.kernel.org
      Reported-by: NMartijn Coenen <maco@google.com>
      Reviewed-by: NBart Van Assche <bvanassche@acm.org>
      Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      5aa6c2bd
    • T
      loop: Fix double mutex_unlock(&loop_ctl_mutex) in loop_control_ioctl() · 10d99516
      Tetsuo Handa 提交于
      commit 628bd859 upstream.
      
      Commit 0a42e99b ("loop: Get rid of loop_index_mutex") forgot to
      remove mutex_unlock(&loop_ctl_mutex) from loop_control_ioctl() when
      replacing loop_index_mutex with loop_ctl_mutex.
      
      Fixes: 0a42e99b ("loop: Get rid of loop_index_mutex")
      Reported-by: Nsyzbot <syzbot+c0138741c2290fc5e63f@syzkaller.appspotmail.com>
      Reviewed-by: NMing Lei <ming.lei@redhat.com>
      Reviewed-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      10d99516
    • J
      loop: Get rid of 'nested' acquisition of loop_ctl_mutex · afa52890
      Jan Kara 提交于
      commit c28445fa upstream.
      
      The nested acquisition of loop_ctl_mutex (->lo_ctl_mutex back then) has
      been introduced by commit f028f3b2 "loop: fix circular locking in
      loop_clr_fd()" to fix lockdep complains about bd_mutex being acquired
      after lo_ctl_mutex during partition rereading. Now that these are
      properly fixed, let's stop fooling lockdep.
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      afa52890
    • J
      loop: Avoid circular locking dependency between loop_ctl_mutex and bd_mutex · f6a4402f
      Jan Kara 提交于
      commit 1dded9ac upstream.
      
      Code in loop_change_fd() drops reference to the old file (and also the
      new file in a failure case) under loop_ctl_mutex. Similarly to a
      situation in loop_set_fd() this can create a circular locking dependency
      if this was the last reference holding the file open. Delay dropping of
      the file reference until we have released loop_ctl_mutex.
      Reported-by: NTetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      f6a4402f
    • J
      loop: Fix deadlock when calling blkdev_reread_part() · 92344edf
      Jan Kara 提交于
      commit 0da03cab upstream.
      
      Calling blkdev_reread_part() under loop_ctl_mutex causes lockdep to
      complain about circular lock dependency between bdev->bd_mutex and
      lo->lo_ctl_mutex. The problem is that on loop device open or close
      lo_open() and lo_release() get called with bdev->bd_mutex held and they
      need to acquire loop_ctl_mutex. OTOH when loop_reread_partitions() is
      called with loop_ctl_mutex held, it will call blkdev_reread_part() which
      acquires bdev->bd_mutex. See syzbot report for details [1].
      
      Move call to blkdev_reread_part() in __loop_clr_fd() from under
      loop_ctl_mutex to finish fixing of the lockdep warning and the possible
      deadlock.
      
      [1] https://syzkaller.appspot.com/bug?id=bf154052f0eea4bc7712499e4569505907d1588Reported-by: Nsyzbot <syzbot+4684a000d5abdade83fac55b1e7d1f935ef1936e@syzkaller.appspotmail.com>
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      92344edf
    • J
      loop: Move loop_reread_partitions() out of loop_ctl_mutex · 2a7d0112
      Jan Kara 提交于
      commit 85b0a54a upstream.
      
      Calling loop_reread_partitions() under loop_ctl_mutex causes lockdep to
      complain about circular lock dependency between bdev->bd_mutex and
      lo->lo_ctl_mutex. The problem is that on loop device open or close
      lo_open() and lo_release() get called with bdev->bd_mutex held and they
      need to acquire loop_ctl_mutex. OTOH when loop_reread_partitions() is
      called with loop_ctl_mutex held, it will call blkdev_reread_part() which
      acquires bdev->bd_mutex. See syzbot report for details [1].
      
      Move all calls of loop_rescan_partitions() out of loop_ctl_mutex to
      avoid lockdep warning and fix deadlock possibility.
      
      [1] https://syzkaller.appspot.com/bug?id=bf154052f0eea4bc7712499e4569505907d1588Reported-by: Nsyzbot <syzbot+4684a000d5abdade83fac55b1e7d1f935ef1936e@syzkaller.appspotmail.com>
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      2a7d0112
    • J
      loop: Move special partition reread handling in loop_clr_fd() · 2797232d
      Jan Kara 提交于
      commit d57f3374 upstream.
      
      The call of __blkdev_reread_part() from loop_reread_partition() happens
      only when we need to invalidate partitions from loop_release(). Thus
      move a detection for this into loop_clr_fd() and simplify
      loop_reread_partition().
      
      This makes loop_reread_partition() safe to use without loop_ctl_mutex
      because we use only lo->lo_number and lo->lo_file_name in case of error
      for reporting purposes (thus possibly reporting outdate information is
      not a big deal) and we are safe from 'lo' going away under us by
      elevated lo->lo_refcnt.
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      2797232d
    • J
      loop: Push loop_ctl_mutex down to loop_change_fd() · d8521992
      Jan Kara 提交于
      commit c3710770 upstream.
      
      Push loop_ctl_mutex down to loop_change_fd(). We will need this to be
      able to call loop_reread_partitions() without loop_ctl_mutex.
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      d8521992
    • J
      loop: Push loop_ctl_mutex down to loop_set_fd() · 972c45f0
      Jan Kara 提交于
      commit 757ecf40 upstream.
      
      Push lo_ctl_mutex down to loop_set_fd(). We will need this to be able to
      call loop_reread_partitions() without lo_ctl_mutex.
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      972c45f0
    • J
      loop: Push loop_ctl_mutex down to loop_set_status() · cb26630f
      Jan Kara 提交于
      commit 550df5fd upstream.
      
      Push loop_ctl_mutex down to loop_set_status(). We will need this to be
      able to call loop_reread_partitions() without loop_ctl_mutex.
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      cb26630f
    • J
      loop: Push loop_ctl_mutex down to loop_get_status() · 4092e3c4
      Jan Kara 提交于
      commit 4a5ce9ba upstream.
      
      Push loop_ctl_mutex down to loop_get_status() to avoid the unusual
      convention that the function gets called with loop_ctl_mutex held and
      releases it.
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      4092e3c4
    • J
      loop: Push loop_ctl_mutex down into loop_clr_fd() · 2ec21106
      Jan Kara 提交于
      commit 7ccd0791 upstream.
      
      loop_clr_fd() has a weird locking convention that is expects
      loop_ctl_mutex held, releases it on success and keeps it on failure.
      Untangle the mess by moving locking of loop_ctl_mutex into
      loop_clr_fd().
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      2ec21106
    • J
      loop: Split setting of lo_state from loop_clr_fd · 04799b3a
      Jan Kara 提交于
      commit a2505b79 upstream.
      
      Move setting of lo_state to Lo_rundown out into the callers. That will
      allow us to unlock loop_ctl_mutex while the loop device is protected
      from other changes by its special state.
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      04799b3a
    • J
      loop: Push lo_ctl_mutex down into individual ioctls · 03305420
      Jan Kara 提交于
      commit a1316544 upstream.
      
      Push acquisition of lo_ctl_mutex down into individual ioctl handling
      branches. This is a preparatory step for pushing the lock down into
      individual ioctl handling functions so that they can release the lock as
      they need it. We also factor out some simple ioctl handlers that will
      not need any special handling to reduce unnecessary code duplication.
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      03305420
    • J
      loop: Get rid of loop_index_mutex · b756e0f4
      Jan Kara 提交于
      commit 0a42e99b upstream.
      
      Now that loop_ctl_mutex is global, just get rid of loop_index_mutex as
      there is no good reason to keep these two separate and it just
      complicates the locking.
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      b756e0f4
    • J
      loop: Fold __loop_release into loop_release · 9e6be9a9
      Jan Kara 提交于
      commit 967d1dc1 upstream.
      
      __loop_release() has a single call site. Fold it there. This is
      currently not a huge win but it will make following replacement of
      loop_index_mutex more obvious.
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      9e6be9a9
    • T
      block/loop: Use global lock for ioctl() operation. · c844e4fa
      Tetsuo Handa 提交于
      commit 310ca162 upstream.
      
      syzbot is reporting NULL pointer dereference [1] which is caused by
      race condition between ioctl(loop_fd, LOOP_CLR_FD, 0) versus
      ioctl(other_loop_fd, LOOP_SET_FD, loop_fd) due to traversing other
      loop devices at loop_validate_file() without holding corresponding
      lo->lo_ctl_mutex locks.
      
      Since ioctl() request on loop devices is not frequent operation, we don't
      need fine grained locking. Let's use global lock in order to allow safe
      traversal at loop_validate_file().
      
      Note that syzbot is also reporting circular locking dependency between
      bdev->bd_mutex and lo->lo_ctl_mutex [2] which is caused by calling
      blkdev_reread_part() with lock held. This patch does not address it.
      
      [1] https://syzkaller.appspot.com/bug?id=f3cfe26e785d85f9ee259f385515291d21bd80a3
      [2] https://syzkaller.appspot.com/bug?id=bf154052f0eea4bc7712499e4569505907d15889Signed-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
      Reported-by: Nsyzbot <syzbot+bf89c128e05dd6c62523@syzkaller.appspotmail.com>
      Reviewed-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      c844e4fa
    • T
      block/loop: Don't grab "struct file" for vfs_getattr() operation. · b9b9108d
      Tetsuo Handa 提交于
      commit b1ab5fa3 upstream.
      
      vfs_getattr() needs "struct path" rather than "struct file".
      Let's use path_get()/path_put() rather than get_file()/fput().
      Signed-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
      Reviewed-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      b9b9108d
    • Y
      tipc: fix uninit-value in tipc_nl_compat_doit · 7503e117
      Ying Xue 提交于
      commit 2753ca5d upstream.
      
      BUG: KMSAN: uninit-value in tipc_nl_compat_doit+0x404/0xa10 net/tipc/netlink_compat.c:335
      CPU: 0 PID: 4514 Comm: syz-executor485 Not tainted 4.16.0+ #87
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
      Call Trace:
       __dump_stack lib/dump_stack.c:17 [inline]
       dump_stack+0x185/0x1d0 lib/dump_stack.c:53
       kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
       __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683
       tipc_nl_compat_doit+0x404/0xa10 net/tipc/netlink_compat.c:335
       tipc_nl_compat_recv+0x164b/0x2700 net/tipc/netlink_compat.c:1153
       genl_family_rcv_msg net/netlink/genetlink.c:599 [inline]
       genl_rcv_msg+0x1686/0x1810 net/netlink/genetlink.c:624
       netlink_rcv_skb+0x378/0x600 net/netlink/af_netlink.c:2447
       genl_rcv+0x63/0x80 net/netlink/genetlink.c:635
       netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline]
       netlink_unicast+0x166b/0x1740 net/netlink/af_netlink.c:1337
       netlink_sendmsg+0x1048/0x1310 net/netlink/af_netlink.c:1900
       sock_sendmsg_nosec net/socket.c:630 [inline]
       sock_sendmsg net/socket.c:640 [inline]
       ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046
       __sys_sendmsg net/socket.c:2080 [inline]
       SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091
       SyS_sendmsg+0x54/0x80 net/socket.c:2087
       do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
       entry_SYSCALL_64_after_hwframe+0x3d/0xa2
      RIP: 0033:0x43fda9
      RSP: 002b:00007ffd0c184ba8 EFLAGS: 00000213 ORIG_RAX: 000000000000002e
      RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fda9
      RDX: 0000000000000000 RSI: 0000000020023000 RDI: 0000000000000003
      RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
      R10: 00000000004002c8 R11: 0000000000000213 R12: 00000000004016d0
      R13: 0000000000401760 R14: 0000000000000000 R15: 0000000000000000
      
      Uninit was created at:
       kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
       kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188
       kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314
       kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321
       slab_post_alloc_hook mm/slab.h:445 [inline]
       slab_alloc_node mm/slub.c:2737 [inline]
       __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369
       __kmalloc_reserve net/core/skbuff.c:138 [inline]
       __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206
       alloc_skb include/linux/skbuff.h:984 [inline]
       netlink_alloc_large_skb net/netlink/af_netlink.c:1183 [inline]
       netlink_sendmsg+0x9a6/0x1310 net/netlink/af_netlink.c:1875
       sock_sendmsg_nosec net/socket.c:630 [inline]
       sock_sendmsg net/socket.c:640 [inline]
       ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046
       __sys_sendmsg net/socket.c:2080 [inline]
       SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091
       SyS_sendmsg+0x54/0x80 net/socket.c:2087
       do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
       entry_SYSCALL_64_after_hwframe+0x3d/0xa2
      
      In tipc_nl_compat_recv(), when the len variable returned by
      nlmsg_attrlen() is 0, the message is still treated as a valid one,
      which is obviously unresonable. When len is zero, it means the
      message not only doesn't contain any valid TLV payload, but also
      TLV header is not included. Under this stituation, tlv_type field
      in TLV header is still accessed in tipc_nl_compat_dumpit() or
      tipc_nl_compat_doit(), but the field space is obviously illegal.
      Of course, it is not initialized.
      
      Reported-by: syzbot+bca0dc46634781f08b38@syzkaller.appspotmail.com
      Reported-by: syzbot+6bdb590321a7ae40c1a6@syzkaller.appspotmail.com
      Signed-off-by: NYing Xue <ying.xue@windriver.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      7503e117
    • Y
      tipc: fix uninit-value in tipc_nl_compat_name_table_dump · 6b6e4d25
      Ying Xue 提交于
      commit 974cb0e3 upstream.
      
      syzbot reported:
      
      BUG: KMSAN: uninit-value in __arch_swab32 arch/x86/include/uapi/asm/swab.h:10 [inline]
      BUG: KMSAN: uninit-value in __fswab32 include/uapi/linux/swab.h:59 [inline]
      BUG: KMSAN: uninit-value in tipc_nl_compat_name_table_dump+0x4a8/0xba0 net/tipc/netlink_compat.c:826
      CPU: 0 PID: 6290 Comm: syz-executor848 Not tainted 4.19.0-rc8+ #70
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
      Call Trace:
       __dump_stack lib/dump_stack.c:77 [inline]
       dump_stack+0x306/0x460 lib/dump_stack.c:113
       kmsan_report+0x1a2/0x2e0 mm/kmsan/kmsan.c:917
       __msan_warning+0x7c/0xe0 mm/kmsan/kmsan_instr.c:500
       __arch_swab32 arch/x86/include/uapi/asm/swab.h:10 [inline]
       __fswab32 include/uapi/linux/swab.h:59 [inline]
       tipc_nl_compat_name_table_dump+0x4a8/0xba0 net/tipc/netlink_compat.c:826
       __tipc_nl_compat_dumpit+0x59e/0xdb0 net/tipc/netlink_compat.c:205
       tipc_nl_compat_dumpit+0x63a/0x820 net/tipc/netlink_compat.c:270
       tipc_nl_compat_handle net/tipc/netlink_compat.c:1151 [inline]
       tipc_nl_compat_recv+0x1402/0x2760 net/tipc/netlink_compat.c:1210
       genl_family_rcv_msg net/netlink/genetlink.c:601 [inline]
       genl_rcv_msg+0x185c/0x1a20 net/netlink/genetlink.c:626
       netlink_rcv_skb+0x394/0x640 net/netlink/af_netlink.c:2454
       genl_rcv+0x63/0x80 net/netlink/genetlink.c:637
       netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
       netlink_unicast+0x166d/0x1720 net/netlink/af_netlink.c:1343
       netlink_sendmsg+0x1391/0x1420 net/netlink/af_netlink.c:1908
       sock_sendmsg_nosec net/socket.c:621 [inline]
       sock_sendmsg net/socket.c:631 [inline]
       ___sys_sendmsg+0xe47/0x1200 net/socket.c:2116
       __sys_sendmsg net/socket.c:2154 [inline]
       __do_sys_sendmsg net/socket.c:2163 [inline]
       __se_sys_sendmsg+0x307/0x460 net/socket.c:2161
       __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
       do_syscall_64+0xbe/0x100 arch/x86/entry/common.c:291
       entry_SYSCALL_64_after_hwframe+0x63/0xe7
      RIP: 0033:0x440179
      Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
      RSP: 002b:00007ffecec49318 EFLAGS: 00000213 ORIG_RAX: 000000000000002e
      RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440179
      RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003
      RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8
      R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401a00
      R13: 0000000000401a90 R14: 0000000000000000 R15: 0000000000000000
      
      Uninit was created at:
       kmsan_save_stack_with_flags mm/kmsan/kmsan.c:255 [inline]
       kmsan_internal_poison_shadow+0xc8/0x1d0 mm/kmsan/kmsan.c:180
       kmsan_kmalloc+0xa4/0x120 mm/kmsan/kmsan_hooks.c:104
       kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan_hooks.c:113
       slab_post_alloc_hook mm/slab.h:446 [inline]
       slab_alloc_node mm/slub.c:2727 [inline]
       __kmalloc_node_track_caller+0xb43/0x1400 mm/slub.c:4360
       __kmalloc_reserve net/core/skbuff.c:138 [inline]
       __alloc_skb+0x422/0xe90 net/core/skbuff.c:206
       alloc_skb include/linux/skbuff.h:996 [inline]
       netlink_alloc_large_skb net/netlink/af_netlink.c:1189 [inline]
       netlink_sendmsg+0xcaf/0x1420 net/netlink/af_netlink.c:1883
       sock_sendmsg_nosec net/socket.c:621 [inline]
       sock_sendmsg net/socket.c:631 [inline]
       ___sys_sendmsg+0xe47/0x1200 net/socket.c:2116
       __sys_sendmsg net/socket.c:2154 [inline]
       __do_sys_sendmsg net/socket.c:2163 [inline]
       __se_sys_sendmsg+0x307/0x460 net/socket.c:2161
       __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
       do_syscall_64+0xbe/0x100 arch/x86/entry/common.c:291
       entry_SYSCALL_64_after_hwframe+0x63/0xe7
      
      We cannot take for granted the thing that the length of data contained
      in TLV is longer than the size of struct tipc_name_table_query in
      tipc_nl_compat_name_table_dump().
      
      Reported-by: syzbot+06e771a754829716a327@syzkaller.appspotmail.com
      Signed-off-by: NYing Xue <ying.xue@windriver.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      6b6e4d25
    • Y
      tipc: fix uninit-value in tipc_nl_compat_link_set · a5e54bc8
      Ying Xue 提交于
      commit edf5ff04 upstream.
      
      syzbot reports following splat:
      
      BUG: KMSAN: uninit-value in strlen+0x3b/0xa0 lib/string.c:486
      CPU: 1 PID: 9306 Comm: syz-executor172 Not tainted 4.20.0-rc7+ #2
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
      Google 01/01/2011
      Call Trace:
        __dump_stack lib/dump_stack.c:77 [inline]
        dump_stack+0x173/0x1d0 lib/dump_stack.c:113
        kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:613
        __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:313
        strlen+0x3b/0xa0 lib/string.c:486
        nla_put_string include/net/netlink.h:1154 [inline]
        __tipc_nl_compat_link_set net/tipc/netlink_compat.c:708 [inline]
        tipc_nl_compat_link_set+0x929/0x1220 net/tipc/netlink_compat.c:744
        __tipc_nl_compat_doit net/tipc/netlink_compat.c:311 [inline]
        tipc_nl_compat_doit+0x3aa/0xaf0 net/tipc/netlink_compat.c:344
        tipc_nl_compat_handle net/tipc/netlink_compat.c:1107 [inline]
        tipc_nl_compat_recv+0x14d7/0x2760 net/tipc/netlink_compat.c:1210
        genl_family_rcv_msg net/netlink/genetlink.c:601 [inline]
        genl_rcv_msg+0x185f/0x1a60 net/netlink/genetlink.c:626
        netlink_rcv_skb+0x444/0x640 net/netlink/af_netlink.c:2477
        genl_rcv+0x63/0x80 net/netlink/genetlink.c:637
        netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
        netlink_unicast+0xf40/0x1020 net/netlink/af_netlink.c:1336
        netlink_sendmsg+0x127f/0x1300 net/netlink/af_netlink.c:1917
        sock_sendmsg_nosec net/socket.c:621 [inline]
        sock_sendmsg net/socket.c:631 [inline]
        ___sys_sendmsg+0xdb9/0x11b0 net/socket.c:2116
        __sys_sendmsg net/socket.c:2154 [inline]
        __do_sys_sendmsg net/socket.c:2163 [inline]
        __se_sys_sendmsg+0x305/0x460 net/socket.c:2161
        __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
        do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
        entry_SYSCALL_64_after_hwframe+0x63/0xe7
      
      The uninitialised access happened in
          nla_put_string(skb, TIPC_NLA_LINK_NAME, lc->name)
      
      This is because lc->name string is not validated before it's used.
      
      Reported-by: syzbot+d78b8a29241a195aefb8@syzkaller.appspotmail.com
      Signed-off-by: NYing Xue <ying.xue@windriver.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      a5e54bc8
    • Y
      tipc: fix uninit-value in tipc_nl_compat_bearer_enable · a60a86f2
      Ying Xue 提交于
      commit 0762216c upstream.
      
      syzbot reported:
      
      BUG: KMSAN: uninit-value in strlen+0x3b/0xa0 lib/string.c:484
      CPU: 1 PID: 6371 Comm: syz-executor652 Not tainted 4.19.0-rc8+ #70
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
      Call Trace:
       __dump_stack lib/dump_stack.c:77 [inline]
       dump_stack+0x306/0x460 lib/dump_stack.c:113
       kmsan_report+0x1a2/0x2e0 mm/kmsan/kmsan.c:917
       __msan_warning+0x7c/0xe0 mm/kmsan/kmsan_instr.c:500
       strlen+0x3b/0xa0 lib/string.c:484
       nla_put_string include/net/netlink.h:1011 [inline]
       tipc_nl_compat_bearer_enable+0x238/0x7b0 net/tipc/netlink_compat.c:389
       __tipc_nl_compat_doit net/tipc/netlink_compat.c:311 [inline]
       tipc_nl_compat_doit+0x39f/0xae0 net/tipc/netlink_compat.c:344
       tipc_nl_compat_recv+0x147c/0x2760 net/tipc/netlink_compat.c:1107
       genl_family_rcv_msg net/netlink/genetlink.c:601 [inline]
       genl_rcv_msg+0x185c/0x1a20 net/netlink/genetlink.c:626
       netlink_rcv_skb+0x394/0x640 net/netlink/af_netlink.c:2454
       genl_rcv+0x63/0x80 net/netlink/genetlink.c:637
       netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
       netlink_unicast+0x166d/0x1720 net/netlink/af_netlink.c:1343
       netlink_sendmsg+0x1391/0x1420 net/netlink/af_netlink.c:1908
       sock_sendmsg_nosec net/socket.c:621 [inline]
       sock_sendmsg net/socket.c:631 [inline]
       ___sys_sendmsg+0xe47/0x1200 net/socket.c:2116
       __sys_sendmsg net/socket.c:2154 [inline]
       __do_sys_sendmsg net/socket.c:2163 [inline]
       __se_sys_sendmsg+0x307/0x460 net/socket.c:2161
       __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
       do_syscall_64+0xbe/0x100 arch/x86/entry/common.c:291
       entry_SYSCALL_64_after_hwframe+0x63/0xe7
      RIP: 0033:0x440179
      Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
      RSP: 002b:00007fffef7beee8 EFLAGS: 00000213 ORIG_RAX: 000000000000002e
      RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440179
      RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003
      RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8
      R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401a00
      R13: 0000000000401a90 R14: 0000000000000000 R15: 0000000000000000
      
      Uninit was created at:
       kmsan_save_stack_with_flags mm/kmsan/kmsan.c:255 [inline]
       kmsan_internal_poison_shadow+0xc8/0x1d0 mm/kmsan/kmsan.c:180
       kmsan_kmalloc+0xa4/0x120 mm/kmsan/kmsan_hooks.c:104
       kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan_hooks.c:113
       slab_post_alloc_hook mm/slab.h:446 [inline]
       slab_alloc_node mm/slub.c:2727 [inline]
       __kmalloc_node_track_caller+0xb43/0x1400 mm/slub.c:4360
       __kmalloc_reserve net/core/skbuff.c:138 [inline]
       __alloc_skb+0x422/0xe90 net/core/skbuff.c:206
       alloc_skb include/linux/skbuff.h:996 [inline]
       netlink_alloc_large_skb net/netlink/af_netlink.c:1189 [inline]
       netlink_sendmsg+0xcaf/0x1420 net/netlink/af_netlink.c:1883
       sock_sendmsg_nosec net/socket.c:621 [inline]
       sock_sendmsg net/socket.c:631 [inline]
       ___sys_sendmsg+0xe47/0x1200 net/socket.c:2116
       __sys_sendmsg net/socket.c:2154 [inline]
       __do_sys_sendmsg net/socket.c:2163 [inline]
       __se_sys_sendmsg+0x307/0x460 net/socket.c:2161
       __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
       do_syscall_64+0xbe/0x100 arch/x86/entry/common.c:291
       entry_SYSCALL_64_after_hwframe+0x63/0xe7
      
      The root cause is that we don't validate whether bear name is a valid
      string in tipc_nl_compat_bearer_enable().
      
      Meanwhile, we also fix the same issue in the following functions:
      tipc_nl_compat_bearer_disable()
      tipc_nl_compat_link_stat_dump()
      tipc_nl_compat_media_set()
      tipc_nl_compat_bearer_set()
      
      Reported-by: syzbot+b33d5cae0efd35dbfe77@syzkaller.appspotmail.com
      Signed-off-by: NYing Xue <ying.xue@windriver.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      a60a86f2
    • Y
      tipc: fix uninit-value in tipc_nl_compat_link_reset_stats · e2cecb3b
      Ying Xue 提交于
      commit 8b66fee7 upstream.
      
      syzbot reports following splat:
      
      BUG: KMSAN: uninit-value in strlen+0x3b/0xa0 lib/string.c:486
      CPU: 1 PID: 11057 Comm: syz-executor0 Not tainted 4.20.0-rc7+ #2
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
      Call Trace:
       __dump_stack lib/dump_stack.c:77 [inline]
       dump_stack+0x173/0x1d0 lib/dump_stack.c:113
       kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:613
       __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:295
       strlen+0x3b/0xa0 lib/string.c:486
       nla_put_string include/net/netlink.h:1154 [inline]
       tipc_nl_compat_link_reset_stats+0x1f0/0x360 net/tipc/netlink_compat.c:760
       __tipc_nl_compat_doit net/tipc/netlink_compat.c:311 [inline]
       tipc_nl_compat_doit+0x3aa/0xaf0 net/tipc/netlink_compat.c:344
       tipc_nl_compat_handle net/tipc/netlink_compat.c:1107 [inline]
       tipc_nl_compat_recv+0x14d7/0x2760 net/tipc/netlink_compat.c:1210
       genl_family_rcv_msg net/netlink/genetlink.c:601 [inline]
       genl_rcv_msg+0x185f/0x1a60 net/netlink/genetlink.c:626
       netlink_rcv_skb+0x444/0x640 net/netlink/af_netlink.c:2477
       genl_rcv+0x63/0x80 net/netlink/genetlink.c:637
       netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
       netlink_unicast+0xf40/0x1020 net/netlink/af_netlink.c:1336
       netlink_sendmsg+0x127f/0x1300 net/netlink/af_netlink.c:1917
       sock_sendmsg_nosec net/socket.c:621 [inline]
       sock_sendmsg net/socket.c:631 [inline]
       ___sys_sendmsg+0xdb9/0x11b0 net/socket.c:2116
       __sys_sendmsg net/socket.c:2154 [inline]
       __do_sys_sendmsg net/socket.c:2163 [inline]
       __se_sys_sendmsg+0x305/0x460 net/socket.c:2161
       __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
       do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
       entry_SYSCALL_64_after_hwframe+0x63/0xe7
      RIP: 0033:0x457ec9
      Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 <48> 3d 01 f0 ff ff 0f 83 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
      RSP: 002b:00007f2557338c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
      RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9
      RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000003
      RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
      R10: 0000000000000000 R11: 0000000000000246 R12: 00007f25573396d4
      R13: 00000000004cb478 R14: 00000000004d86c8 R15: 00000000ffffffff
      
      Uninit was created at:
       kmsan_save_stack_with_flags mm/kmsan/kmsan.c:204 [inline]
       kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:158
       kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176
       kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:185
       slab_post_alloc_hook mm/slab.h:446 [inline]
       slab_alloc_node mm/slub.c:2759 [inline]
       __kmalloc_node_track_caller+0xe18/0x1030 mm/slub.c:4383
       __kmalloc_reserve net/core/skbuff.c:137 [inline]
       __alloc_skb+0x309/0xa20 net/core/skbuff.c:205
       alloc_skb include/linux/skbuff.h:998 [inline]
       netlink_alloc_large_skb net/netlink/af_netlink.c:1182 [inline]
       netlink_sendmsg+0xb82/0x1300 net/netlink/af_netlink.c:1892
       sock_sendmsg_nosec net/socket.c:621 [inline]
       sock_sendmsg net/socket.c:631 [inline]
       ___sys_sendmsg+0xdb9/0x11b0 net/socket.c:2116
       __sys_sendmsg net/socket.c:2154 [inline]
       __do_sys_sendmsg net/socket.c:2163 [inline]
       __se_sys_sendmsg+0x305/0x460 net/socket.c:2161
       __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
       do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
       entry_SYSCALL_64_after_hwframe+0x63/0xe7
      
      The uninitialised access happened in tipc_nl_compat_link_reset_stats:
          nla_put_string(skb, TIPC_NLA_LINK_NAME, name)
      
      This is because name string is not validated before it's used.
      
      Reported-by: syzbot+e01d94b5a4c266be6e4c@syzkaller.appspotmail.com
      Signed-off-by: NYing Xue <ying.xue@windriver.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      e2cecb3b
    • Y
      tipc: fix uninit-value in in tipc_conn_rcv_sub · f2ac24ff
      Ying Xue 提交于
      commit a88289f4 upstream.
      
      syzbot reported:
      
      BUG: KMSAN: uninit-value in tipc_conn_rcv_sub+0x184/0x950 net/tipc/topsrv.c:373
      CPU: 0 PID: 66 Comm: kworker/u4:4 Not tainted 4.17.0-rc3+ #88
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
      Workqueue: tipc_rcv tipc_conn_recv_work
      Call Trace:
       __dump_stack lib/dump_stack.c:77 [inline]
       dump_stack+0x185/0x1d0 lib/dump_stack.c:113
       kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
       __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683
       tipc_conn_rcv_sub+0x184/0x950 net/tipc/topsrv.c:373
       tipc_conn_rcv_from_sock net/tipc/topsrv.c:409 [inline]
       tipc_conn_recv_work+0x3cd/0x560 net/tipc/topsrv.c:424
       process_one_work+0x12c6/0x1f60 kernel/workqueue.c:2145
       worker_thread+0x113c/0x24f0 kernel/workqueue.c:2279
       kthread+0x539/0x720 kernel/kthread.c:239
       ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:412
      
      Local variable description: ----s.i@tipc_conn_recv_work
      Variable was created at:
       tipc_conn_recv_work+0x65/0x560 net/tipc/topsrv.c:419
       process_one_work+0x12c6/0x1f60 kernel/workqueue.c:2145
      
      In tipc_conn_rcv_from_sock(), it always supposes the length of message
      received from sock_recvmsg() is not smaller than the size of struct
      tipc_subscr. However, this assumption is false. Especially when the
      length of received message is shorter than struct tipc_subscr size,
      we will end up touching uninitialized fields in tipc_conn_rcv_sub().
      
      Reported-by: syzbot+8951a3065ee7fd6d6e23@syzkaller.appspotmail.com
      Reported-by: syzbot+75e6e042c5bbf691fc82@syzkaller.appspotmail.com
      Signed-off-by: NYing Xue <ying.xue@windriver.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      f2ac24ff
    • X
      sctp: allocate sctp_sockaddr_entry with kzalloc · 2906591a
      Xin Long 提交于
      commit 400b8b9a upstream.
      
      The similar issue as fixed in Commit 4a2eb0c3 ("sctp: initialize
      sin6_flowinfo for ipv6 addrs in sctp_inet6addr_event") also exists
      in sctp_inetaddr_event, as Alexander noticed.
      
      To fix it, allocate sctp_sockaddr_entry with kzalloc for both sctp
      ipv4 and ipv6 addresses, as does in sctp_v4/6_copy_addrlist().
      Reported-by: NAlexander Potapenko <glider@google.com>
      Signed-off-by: NXin Long <lucien.xin@gmail.com>
      Reported-by: syzbot+ae0c70c0c2d40c51bb92@syzkaller.appspotmail.com
      Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
      Acked-by: NNeil Horman <nhorman@tuxdriver.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      2906591a
    • J
      blockdev: Fix livelocks on loop device · d09d64b8
      Jan Kara 提交于
      commit 04906b2f542c23626b0ef6219b808406f8dddbe9 upstream.
      
      bd_set_size() updates also block device's block size. This is somewhat
      unexpected from its name and at this point, only blkdev_open() uses this
      functionality. Furthermore, this can result in changing block size under
      a filesystem mounted on a loop device which leads to livelocks inside
      __getblk_gfp() like:
      
      Sending NMI from CPU 0 to CPUs 1:
      NMI backtrace for cpu 1
      CPU: 1 PID: 10863 Comm: syz-executor0 Not tainted 4.18.0-rc5+ #151
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google
      01/01/2011
      RIP: 0010:__sanitizer_cov_trace_pc+0x3f/0x50 kernel/kcov.c:106
      ...
      Call Trace:
       init_page_buffers+0x3e2/0x530 fs/buffer.c:904
       grow_dev_page fs/buffer.c:947 [inline]
       grow_buffers fs/buffer.c:1009 [inline]
       __getblk_slow fs/buffer.c:1036 [inline]
       __getblk_gfp+0x906/0xb10 fs/buffer.c:1313
       __bread_gfp+0x2d/0x310 fs/buffer.c:1347
       sb_bread include/linux/buffer_head.h:307 [inline]
       fat12_ent_bread+0x14e/0x3d0 fs/fat/fatent.c:75
       fat_ent_read_block fs/fat/fatent.c:441 [inline]
       fat_alloc_clusters+0x8ce/0x16e0 fs/fat/fatent.c:489
       fat_add_cluster+0x7a/0x150 fs/fat/inode.c:101
       __fat_get_block fs/fat/inode.c:148 [inline]
      ...
      
      Trivial reproducer for the problem looks like:
      
      truncate -s 1G /tmp/image
      losetup /dev/loop0 /tmp/image
      mkfs.ext4 -b 1024 /dev/loop0
      mount -t ext4 /dev/loop0 /mnt
      losetup -c /dev/loop0
      l /mnt
      
      Fix the problem by moving initialization of a block device block size
      into a separate function and call it when needed.
      
      Thanks to Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> for help with
      debugging the problem.
      
      Reported-by: syzbot+9933e4476f365f5d5a1b@syzkaller.appspotmail.com
      Signed-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      d09d64b8
    • S
      selinux: fix GPF on invalid policy · 9b7c338d
      Stephen Smalley 提交于
      commit 5b0e7310a2a33c06edc7eb81ffc521af9b2c5610 upstream.
      
      levdatum->level can be NULL if we encounter an error while loading
      the policy during sens_read prior to initializing it.  Make sure
      sens_destroy handles that case correctly.
      
      Reported-by: syzbot+6664500f0f18f07a5c0e@syzkaller.appspotmail.com
      Signed-off-by: NStephen Smalley <sds@tycho.nsa.gov>
      Signed-off-by: NPaul Moore <paul@paul-moore.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      9b7c338d
    • Y
      block: use rcu_work instead of call_rcu to avoid sleep in softirq · 9b3edcb6
      Yufen Yu 提交于
      commit 94a2c3a3 upstream.
      
      We recently got a stack by syzkaller like this:
      
      BUG: sleeping function called from invalid context at mm/slab.h:361
      in_atomic(): 1, irqs_disabled(): 0, pid: 6644, name: blkid
      INFO: lockdep is turned off.
      CPU: 1 PID: 6644 Comm: blkid Not tainted 4.4.163-514.55.6.9.x86_64+ #76
      Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
       0000000000000000 5ba6a6b879e50c00 ffff8801f6b07b10 ffffffff81cb2194
       0000000041b58ab3 ffffffff833c7745 ffffffff81cb2080 5ba6a6b879e50c00
       0000000000000000 0000000000000001 0000000000000004 0000000000000000
      Call Trace:
       <IRQ>  [<ffffffff81cb2194>] __dump_stack lib/dump_stack.c:15 [inline]
       <IRQ>  [<ffffffff81cb2194>] dump_stack+0x114/0x1a0 lib/dump_stack.c:51
       [<ffffffff8129a981>] ___might_sleep+0x291/0x490 kernel/sched/core.c:7675
       [<ffffffff8129ac33>] __might_sleep+0xb3/0x270 kernel/sched/core.c:7637
       [<ffffffff81794c13>] slab_pre_alloc_hook mm/slab.h:361 [inline]
       [<ffffffff81794c13>] slab_alloc_node mm/slub.c:2610 [inline]
       [<ffffffff81794c13>] slab_alloc mm/slub.c:2692 [inline]
       [<ffffffff81794c13>] kmem_cache_alloc_trace+0x2c3/0x5c0 mm/slub.c:2709
       [<ffffffff81cbe9a7>] kmalloc include/linux/slab.h:479 [inline]
       [<ffffffff81cbe9a7>] kzalloc include/linux/slab.h:623 [inline]
       [<ffffffff81cbe9a7>] kobject_uevent_env+0x2c7/0x1150 lib/kobject_uevent.c:227
       [<ffffffff81cbf84f>] kobject_uevent+0x1f/0x30 lib/kobject_uevent.c:374
       [<ffffffff81cbb5b9>] kobject_cleanup lib/kobject.c:633 [inline]
       [<ffffffff81cbb5b9>] kobject_release+0x229/0x440 lib/kobject.c:675
       [<ffffffff81cbb0a2>] kref_sub include/linux/kref.h:73 [inline]
       [<ffffffff81cbb0a2>] kref_put include/linux/kref.h:98 [inline]
       [<ffffffff81cbb0a2>] kobject_put+0x72/0xd0 lib/kobject.c:692
       [<ffffffff8216f095>] put_device+0x25/0x30 drivers/base/core.c:1237
       [<ffffffff81c4cc34>] delete_partition_rcu_cb+0x1d4/0x2f0 block/partition-generic.c:232
       [<ffffffff813c08bc>] __rcu_reclaim kernel/rcu/rcu.h:118 [inline]
       [<ffffffff813c08bc>] rcu_do_batch kernel/rcu/tree.c:2705 [inline]
       [<ffffffff813c08bc>] invoke_rcu_callbacks kernel/rcu/tree.c:2973 [inline]
       [<ffffffff813c08bc>] __rcu_process_callbacks kernel/rcu/tree.c:2940 [inline]
       [<ffffffff813c08bc>] rcu_process_callbacks+0x59c/0x1c70 kernel/rcu/tree.c:2957
       [<ffffffff8120f509>] __do_softirq+0x299/0xe20 kernel/softirq.c:273
       [<ffffffff81210496>] invoke_softirq kernel/softirq.c:350 [inline]
       [<ffffffff81210496>] irq_exit+0x216/0x2c0 kernel/softirq.c:391
       [<ffffffff82c2cd7b>] exiting_irq arch/x86/include/asm/apic.h:652 [inline]
       [<ffffffff82c2cd7b>] smp_apic_timer_interrupt+0x8b/0xc0 arch/x86/kernel/apic/apic.c:926
       [<ffffffff82c2bc25>] apic_timer_interrupt+0xa5/0xb0 arch/x86/entry/entry_64.S:746
       <EOI>  [<ffffffff814cbf40>] ? audit_kill_trees+0x180/0x180
       [<ffffffff8187d2f7>] fd_install+0x57/0x80 fs/file.c:626
       [<ffffffff8180989e>] do_sys_open+0x45e/0x550 fs/open.c:1043
       [<ffffffff818099c2>] SYSC_open fs/open.c:1055 [inline]
       [<ffffffff818099c2>] SyS_open+0x32/0x40 fs/open.c:1050
       [<ffffffff82c299e1>] entry_SYSCALL_64_fastpath+0x1e/0x9a
      
      In softirq context, we call rcu callback function delete_partition_rcu_cb(),
      which may allocate memory by kzalloc with GFP_KERNEL flag. If the
      allocation cannot be satisfied, it may sleep. However, That is not allowed
      in softirq contex.
      
      Although we found this problem on linux 4.4, the latest kernel version
      seems to have this problem as well. And it is very similar to the
      previous one:
      	https://lkml.org/lkml/2018/7/9/391
      
      Fix it by using RCU workqueue, which allows sleep.
      Reviewed-by: NPaul E. McKenney <paulmck@linux.ibm.com>
      Signed-off-by: NYufen Yu <yuyufen@huawei.com>
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      9b3edcb6
    • S
      netfilter: ebtables: account ebt_table_info to kmemcg · 857b3a71
      Shakeel Butt 提交于
      commit e2c8d550 upstream.
      
      The [ip,ip6,arp]_tables use x_tables_info internally and the underlying
      memory is already accounted to kmemcg. Do the same for ebtables. The
      syzbot, by using setsockopt(EBT_SO_SET_ENTRIES), was able to OOM the
      whole system from a restricted memcg, a potential DoS.
      
      By accounting the ebt_table_info, the memory used for ebt_table_info can
      be contained within the memcg of the allocating process. However the
      lifetime of ebt_table_info is independent of the allocating process and
      is tied to the network namespace. So, the oom-killer will not be able to
      relieve the memory pressure due to ebt_table_info memory. The memory for
      ebt_table_info is allocated through vmalloc. Currently vmalloc does not
      handle the oom-killed allocating process correctly and one large
      allocation can bypass memcg limit enforcement. So, with this patch,
      at least the small allocations will be contained. For large allocations,
      we need to fix vmalloc.
      
      Reported-by: syzbot+7713f3aa67be76b1552c@syzkaller.appspotmail.com
      Signed-off-by: NShakeel Butt <shakeelb@google.com>
      Reviewed-by: NKirill Tkhai <ktkhai@virtuozzo.com>
      Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      857b3a71
    • J
      sunrpc: handle ENOMEM in rpcb_getport_async · 1ef931f8
      J. Bruce Fields 提交于
      commit 81c88b18 upstream.
      
      If we ignore the error we'll hit a null dereference a little later.
      
      Reported-by: syzbot+4b98281f2401ab849f4b@syzkaller.appspotmail.com
      Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
      Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      1ef931f8
    • H
      media: vb2: vb2_mmap: move lock up · 6d96b4be
      Hans Verkuil 提交于
      commit cd26d1c4 upstream.
      
      If a filehandle is dup()ped, then it is possible to close it from one fd
      and call mmap from the other. This creates a race condition in vb2_mmap
      where it is using queue data that __vb2_queue_free (called from close())
      is in the process of releasing.
      
      By moving up the mutex_lock(mmap_lock) in vb2_mmap this race is avoided
      since __vb2_queue_free is called with the same mutex locked. So vb2_mmap
      now reads consistent buffer data.
      Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
      Reported-by: syzbot+be93025dd45dccd8923c@syzkaller.appspotmail.com
      Signed-off-by: NHans Verkuil <hansverk@cisco.com>
      Signed-off-by: NMauro Carvalho Chehab <mchehab+samsung@kernel.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      6d96b4be
    • J
      LSM: Check for NULL cred-security on free · f71d4b76
      James Morris 提交于
      commit a5795fd3 upstream.
      
      From: Casey Schaufler <casey@schaufler-ca.com>
      
      Check that the cred security blob has been set before trying
      to clean it up. There is a case during credential initialization
      that could result in this.
      Signed-off-by: NCasey Schaufler <casey@schaufler-ca.com>
      Acked-by: NJohn Johansen <john.johansen@canonical.com>
      Signed-off-by: NJames Morris <james.morris@microsoft.com>
      Reported-by: syzbot+69ca07954461f189e808@syzkaller.appspotmail.com
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      f71d4b76
    • E
      ipv6: make icmp6_send() robust against null skb->dev · 690eac27
      Eric Dumazet 提交于
      commit 8d933670 upstream.
      
      syzbot was able to crash one host with the following stack trace :
      
      kasan: GPF could be caused by NULL-ptr deref or user memory access
      general protection fault: 0000 [#1] PREEMPT SMP KASAN
      CPU: 0 PID: 8625 Comm: syz-executor4 Not tainted 4.20.0+ #8
      RIP: 0010:dev_net include/linux/netdevice.h:2169 [inline]
      RIP: 0010:icmp6_send+0x116/0x2d30 net/ipv6/icmp.c:426
       icmpv6_send
       smack_socket_sock_rcv_skb
       security_sock_rcv_skb
       sk_filter_trim_cap
       __sk_receive_skb
       dccp_v6_do_rcv
       release_sock
      
      This is because a RX packet found socket owned by user and
      was stored into socket backlog. Before leaving RCU protected section,
      skb->dev was cleared in __sk_receive_skb(). When socket backlog
      was finally handled at release_sock() time, skb was fed to
      smack_socket_sock_rcv_skb() then icmp6_send()
      
      We could fix the bug in smack_socket_sock_rcv_skb(), or simply
      make icmp6_send() more robust against such possibility.
      
      In the future we might provide to icmp6_send() the net pointer
      instead of infering it.
      
      Fixes: d66a8acb ("Smack: Inform peer that IPv6 traffic has been blocked")
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Cc: Piotr Sawicki <p.sawicki2@partner.samsung.com>
      Cc: Casey Schaufler <casey@schaufler-ca.com>
      Reported-by: Nsyzbot <syzkaller@googlegroups.com>
      Acked-by: NCasey Schaufler <casey@schaufler-ca.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      690eac27
    • W
      bpf: in __bpf_redirect_no_mac pull mac only if present · 09a68088
      Willem de Bruijn 提交于
      commit e7c87bd6 upstream.
      
      Syzkaller was able to construct a packet of negative length by
      redirecting from bpf_prog_test_run_skb with BPF_PROG_TYPE_LWT_XMIT:
      
          BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:345 [inline]
          BUG: KASAN: slab-out-of-bounds in skb_copy_from_linear_data include/linux/skbuff.h:3421 [inline]
          BUG: KASAN: slab-out-of-bounds in __pskb_copy_fclone+0x2dd/0xeb0 net/core/skbuff.c:1395
          Read of size 4294967282 at addr ffff8801d798009c by task syz-executor2/12942
      
          kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412
          check_memory_region_inline mm/kasan/kasan.c:260 [inline]
          check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
          memcpy+0x23/0x50 mm/kasan/kasan.c:302
          memcpy include/linux/string.h:345 [inline]
          skb_copy_from_linear_data include/linux/skbuff.h:3421 [inline]
          __pskb_copy_fclone+0x2dd/0xeb0 net/core/skbuff.c:1395
          __pskb_copy include/linux/skbuff.h:1053 [inline]
          pskb_copy include/linux/skbuff.h:2904 [inline]
          skb_realloc_headroom+0xe7/0x120 net/core/skbuff.c:1539
          ipip6_tunnel_xmit net/ipv6/sit.c:965 [inline]
          sit_tunnel_xmit+0xe1b/0x30d0 net/ipv6/sit.c:1029
          __netdev_start_xmit include/linux/netdevice.h:4325 [inline]
          netdev_start_xmit include/linux/netdevice.h:4334 [inline]
          xmit_one net/core/dev.c:3219 [inline]
          dev_hard_start_xmit+0x295/0xc90 net/core/dev.c:3235
          __dev_queue_xmit+0x2f0d/0x3950 net/core/dev.c:3805
          dev_queue_xmit+0x17/0x20 net/core/dev.c:3838
          __bpf_tx_skb net/core/filter.c:2016 [inline]
          __bpf_redirect_common net/core/filter.c:2054 [inline]
          __bpf_redirect+0x5cf/0xb20 net/core/filter.c:2061
          ____bpf_clone_redirect net/core/filter.c:2094 [inline]
          bpf_clone_redirect+0x2f6/0x490 net/core/filter.c:2066
          bpf_prog_41f2bcae09cd4ac3+0xb25/0x1000
      
      The generated test constructs a packet with mac header, network
      header, skb->data pointing to network header and skb->len 0.
      
      Redirecting to a sit0 through __bpf_redirect_no_mac pulls the
      mac length, even though skb->data already is at skb->network_header.
      bpf_prog_test_run_skb has already pulled it as LWT_XMIT !is_l2.
      
      Update the offset calculation to pull only if skb->data differs
      from skb->network_header, which is not true in this case.
      
      The test itself can be run only from commit 1cf1cae9 ("bpf:
      introduce BPF_PROG_TEST_RUN command"), but the same type of packets
      with skb at network header could already be built from lwt xmit hooks,
      so this fix is more relevant to that commit.
      
      Also set the mac header on redirect from LWT_XMIT, as even after this
      change to __bpf_redirect_no_mac that field is expected to be set, but
      is not yet in ip_finish_output2.
      
      Fixes: 3a0af8fd ("bpf: BPF for lightweight tunnel infrastructure")
      Reported-by: Nsyzbot <syzkaller@googlegroups.com>
      Signed-off-by: NWillem de Bruijn <willemb@google.com>
      Acked-by: NMartin KaFai Lau <kafai@fb.com>
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      09a68088
    • H
      media: vivid: set min width/height to a value > 0 · 841b7150
      Hans Verkuil 提交于
      commit 9729d6d2 upstream.
      
      The capture DV timings capabilities allowed for a minimum width and
      height of 0. So passing a timings struct with 0 values is allowed
      and will later cause a division by zero.
      
      Ensure that the width and height must be >= 16 to avoid this.
      Signed-off-by: NHans Verkuil <hverkuil-cisco@xs4all.nl>
      Reported-by: syzbot+57c3d83d71187054d56f@syzkaller.appspotmail.com
      Signed-off-by: NMauro Carvalho Chehab <mchehab+samsung@kernel.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      841b7150
    • H
      media: vivid: fix error handling of kthread_run · 3e544789
      Hans Verkuil 提交于
      commit 701f49bc upstream.
      
      kthread_run returns an error pointer, but elsewhere in the code
      dev->kthread_vid_cap/out is checked against NULL.
      
      If kthread_run returns an error, then set the pointer to NULL.
      
      I chose this method over changing all kthread_vid_cap/out tests
      elsewhere since this is more robust.
      Signed-off-by: NHans Verkuil <hverkuil-cisco@xs4all.nl>
      Reported-by: syzbot+53d5b2df0d9744411e2e@syzkaller.appspotmail.com
      Signed-off-by: NMauro Carvalho Chehab <mchehab+samsung@kernel.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      3e544789
    • V
      omap2fb: Fix stack memory disclosure · 5510f2d2
      Vlad Tsyrklevich 提交于
      commit a01421e4 upstream.
      
      Using [1] for static analysis I found that the OMAPFB_QUERY_PLANE,
      OMAPFB_GET_COLOR_KEY, OMAPFB_GET_DISPLAY_INFO, and OMAPFB_GET_VRAM_INFO
      cases could all leak uninitialized stack memory--either due to
      uninitialized padding or 'reserved' fields.
      
      Fix them by clearing the shared union used to store copied out data.
      
      [1] https://github.com/vlad902/kernel-uninitialized-memory-checkerSigned-off-by: NVlad Tsyrklevich <vlad@tsyrklevich.net>
      Reviewed-by: NKees Cook <keescook@chromium.org>
      Fixes: b39a982d ("OMAP: DSS2: omapfb driver")
      Cc: security@kernel.org
      [b.zolnierkie: prefix patch subject with "omap2fb: "]
      Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      5510f2d2
    • F
      fix int_sqrt64() for very large numbers · a6df0d7e
      Florian La Roche 提交于
      commit fbfaf851 upstream.
      
      If an input number x for int_sqrt64() has the highest bit set, then
      fls64(x) is 64.  (1UL << 64) is an overflow and breaks the algorithm.
      
      Subtracting 1 is a better guess for the initial value of m anyway and
      that's what also done in int_sqrt() implicitly [*].
      
      [*] Note how int_sqrt() uses __fls() with two underscores, which already
          returns the proper raw bit number.
      
          In contrast, int_sqrt64() used fls64(), and that returns bit numbers
          illogically starting at 1, because of error handling for the "no
          bits set" case. Will points out that he bug probably is due to a
          copy-and-paste error from the regular int_sqrt() case.
      Signed-off-by: NFlorian La Roche <Florian.LaRoche@googlemail.com>
      Acked-by: NWill Deacon <will.deacon@arm.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
      a6df0d7e