1. 20 Aug, 2016 20 commits
  2. 16 Aug, 2016 20 commits
    • Greg Kroah-Hartman's avatar
      Linux 3.14.76 · c0e754d6
      Greg Kroah-Hartman authored
      c0e754d6
    • Vegard Nossum's avatar
      ext4: fix reference counting bug on block allocation error · 1f5eff58
      Vegard Nossum authored
      commit 554a5ccc upstream.
      
      If we hit this error when mounted with errors=continue or
      errors=remount-ro:
      
          EXT4-fs error (device loop0): ext4_mb_mark_diskspace_used:2940: comm ext4.exe: Allocating blocks 5090-6081 which overlap fs metadata
      
      then ext4_mb_new_blocks() will call ext4_mb_release_context() and try to
      continue. However, ext4_mb_release_context() is the wrong thing to call
      here since we are still actually using the allocation context.
      
      Instead, just error out. We could retry the allocation, but there is a
      possibility of getting stuck in an infinite loop instead, so this seems
      safer.
      
      [ Fixed up so we don't return EAGAIN to userspace. --tytso ]
      
      Fixes: 8556e8f3 ("ext4: Don't allow new groups to be added during block allocation")
      Signed-off-by: default avatarVegard Nossum <vegard.nossum@oracle.com>
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      1f5eff58
    • Eric Dumazet's avatar
      tcp: make challenge acks less predictable · 860c5325
      Eric Dumazet authored
      [ Upstream commit 75ff39cc ]
      
      Yue Cao claims that current host rate limiting of challenge ACKS
      (RFC 5961) could leak enough information to allow a patient attacker
      to hijack TCP sessions. He will soon provide details in an academic
      paper.
      
      This patch increases the default limit from 100 to 1000, and adds
      some randomization so that the attacker can no longer hijack
      sessions without spending a considerable amount of probes.
      
      Based on initial analysis and patch from Linus.
      
      Note that we also have per socket rate limiting, so it is tempting
      to remove the host limit in the future.
      
      v2: randomize the count of challenge acks per second, not the period.
      
      Fixes: 282f23c6 ("tcp: implement RFC 5961 3.2")
      Reported-by: default avatarYue Cao <ycao009@ucr.edu>
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Suggested-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Cc: Yuchung Cheng <ycheng@google.com>
      Cc: Neal Cardwell <ncardwell@google.com>
      Acked-by: default avatarNeal Cardwell <ncardwell@google.com>
      Acked-by: default avatarYuchung Cheng <ycheng@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      860c5325
    • Soheil Hassas Yeganeh's avatar
      tcp: consider recv buf for the initial window scale · d92f45a0
      Soheil Hassas Yeganeh authored
      [ Upstream commit f626300a ]
      
      tcp_select_initial_window() intends to advertise a window
      scaling for the maximum possible window size. To do so,
      it considers the maximum of net.ipv4.tcp_rmem[2] and
      net.core.rmem_max as the only possible upper-bounds.
      However, users with CAP_NET_ADMIN can use SO_RCVBUFFORCE
      to set the socket's receive buffer size to values
      larger than net.ipv4.tcp_rmem[2] and net.core.rmem_max.
      Thus, SO_RCVBUFFORCE is effectively ignored by
      tcp_select_initial_window().
      
      To fix this, consider the maximum of net.ipv4.tcp_rmem[2],
      net.core.rmem_max and socket's initial buffer space.
      
      Fixes: b0573dea ("[NET]: Introduce SO_{SND,RCV}BUFFORCE socket options")
      Signed-off-by: default avatarSoheil Hassas Yeganeh <soheil@google.com>
      Suggested-by: default avatarNeal Cardwell <ncardwell@google.com>
      Acked-by: default avatarNeal Cardwell <ncardwell@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      d92f45a0
    • Vegard Nossum's avatar
      net/irda: fix NULL pointer dereference on memory allocation failure · 8e22cf22
      Vegard Nossum authored
      [ Upstream commit d3e6952c ]
      
      I ran into this:
      
          kasan: CONFIG_KASAN_INLINE enabled
          kasan: GPF could be caused by NULL-ptr deref or user memory access
          general protection fault: 0000 [#1] PREEMPT SMP KASAN
          CPU: 2 PID: 2012 Comm: trinity-c3 Not tainted 4.7.0-rc7+ #19
          Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
          task: ffff8800b745f2c0 ti: ffff880111740000 task.ti: ffff880111740000
          RIP: 0010:[<ffffffff82bbf066>]  [<ffffffff82bbf066>] irttp_connect_request+0x36/0x710
          RSP: 0018:ffff880111747bb8  EFLAGS: 00010286
          RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000069dd8358
          RDX: 0000000000000009 RSI: 0000000000000027 RDI: 0000000000000048
          RBP: ffff880111747c00 R08: 0000000000000000 R09: 0000000000000000
          R10: 0000000069dd8358 R11: 1ffffffff0759723 R12: 0000000000000000
          R13: ffff88011a7e4780 R14: 0000000000000027 R15: 0000000000000000
          FS:  00007fc738404700(0000) GS:ffff88011af00000(0000) knlGS:0000000000000000
          CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
          CR2: 00007fc737fdfb10 CR3: 0000000118087000 CR4: 00000000000006e0
          Stack:
           0000000000000200 ffff880111747bd8 ffffffff810ee611 ffff880119f1f220
           ffff880119f1f4f8 ffff880119f1f4f0 ffff88011a7e4780 ffff880119f1f232
           ffff880119f1f220 ffff880111747d58 ffffffff82bca542 0000000000000000
          Call Trace:
           [<ffffffff82bca542>] irda_connect+0x562/0x1190
           [<ffffffff825ae582>] SYSC_connect+0x202/0x2a0
           [<ffffffff825b4489>] SyS_connect+0x9/0x10
           [<ffffffff8100334c>] do_syscall_64+0x19c/0x410
           [<ffffffff83295ca5>] entry_SYSCALL64_slow_path+0x25/0x25
          Code: 41 89 ca 48 89 e5 41 57 41 56 41 55 41 54 41 89 d7 53 48 89 fb 48 83 c7 48 48 89 fa 41 89 f6 48 c1 ea 03 48 83 ec 20 4c 8b 65 10 <0f> b6 04 02 84 c0 74 08 84 c0 0f 8e 4c 04 00 00 80 7b 48 00 74
          RIP  [<ffffffff82bbf066>] irttp_connect_request+0x36/0x710
           RSP <ffff880111747bb8>
          ---[ end trace 4cda2588bc055b30 ]---
      
      The problem is that irda_open_tsap() can fail and leave self->tsap = NULL,
      and then irttp_connect_request() almost immediately dereferences it.
      
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarVegard Nossum <vegard.nossum@oracle.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      8e22cf22
    • Beniamino Galvani's avatar
      bonding: set carrier off for devices created through netlink · 77039f9b
      Beniamino Galvani authored
      [ Upstream commit 005db31d ]
      
      Commit e826eafa ("bonding: Call netif_carrier_off after
      register_netdevice") moved netif_carrier_off() from bond_init() to
      bond_create(), but the latter is called only for initial default
      devices and ones created through sysfs:
      
       $ modprobe bonding
       $ echo +bond1 > /sys/class/net/bonding_masters
       $ ip link add bond2 type bond
       $ grep "MII Status" /proc/net/bonding/*
       /proc/net/bonding/bond0:MII Status: down
       /proc/net/bonding/bond1:MII Status: down
       /proc/net/bonding/bond2:MII Status: up
      
      Ensure that carrier is initially off also for devices created through
      netlink.
      Signed-off-by: default avatarBeniamino Galvani <bgalvani@redhat.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      77039f9b
    • Vegard Nossum's avatar
      ext4: short-cut orphan cleanup on error · 7564e4b9
      Vegard Nossum authored
      commit c65d5c6c upstream.
      
      If we encounter a filesystem error during orphan cleanup, we should stop.
      Otherwise, we may end up in an infinite loop where the same inode is
      processed again and again.
      
          EXT4-fs (loop0): warning: checktime reached, running e2fsck is recommended
          EXT4-fs error (device loop0): ext4_mb_generate_buddy:758: group 2, block bitmap and bg descriptor inconsistent: 6117 vs 0 free clusters
          Aborting journal on device loop0-8.
          EXT4-fs (loop0): Remounting filesystem read-only
          EXT4-fs error (device loop0) in ext4_free_blocks:4895: Journal has aborted
          EXT4-fs error (device loop0) in ext4_do_update_inode:4893: Journal has aborted
          EXT4-fs error (device loop0) in ext4_do_update_inode:4893: Journal has aborted
          EXT4-fs error (device loop0) in ext4_ext_remove_space:3068: IO failure
          EXT4-fs error (device loop0) in ext4_ext_truncate:4667: Journal has aborted
          EXT4-fs error (device loop0) in ext4_orphan_del:2927: Journal has aborted
          EXT4-fs error (device loop0) in ext4_do_update_inode:4893: Journal has aborted
          EXT4-fs (loop0): Inode 16 (00000000618192a0): orphan list check failed!
          [...]
          EXT4-fs (loop0): Inode 16 (0000000061819748): orphan list check failed!
          [...]
          EXT4-fs (loop0): Inode 16 (0000000061819bf0): orphan list check failed!
          [...]
      
      See-also: c9eb13a9 ("ext4: fix hang when processing corrupted orphaned inode list")
      Cc: Jan Kara <jack@suse.cz>
      Signed-off-by: default avatarVegard Nossum <vegard.nossum@oracle.com>
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      7564e4b9
    • Vegard Nossum's avatar
      ext4: don't call ext4_should_journal_data() on the journal inode · e02a6ea5
      Vegard Nossum authored
      commit 6a7fd522 upstream.
      
      If ext4_fill_super() fails early, it's possible for ext4_evict_inode()
      to call ext4_should_journal_data() before superblock options and flags
      are fully set up.  In that case, the iput() on the journal inode can
      end up causing a BUG().
      
      Work around this problem by reordering the tests so we only call
      ext4_should_journal_data() after we know it's not the journal inode.
      
      Fixes: 2d859db3 ("ext4: fix data corruption in inodes with journalled data")
      Fixes: 2b405bfa ("ext4: fix data=journal fast mount/umount hang")
      Cc: Jan Kara <jack@suse.cz>
      Signed-off-by: default avatarVegard Nossum <vegard.nossum@oracle.com>
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      Reviewed-by: default avatarJan Kara <jack@suse.cz>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      e02a6ea5
    • Jan Kara's avatar
      ext4: fix deadlock during page writeback · 6e853b16
      Jan Kara authored
      commit 646caa9c upstream.
      
      Commit 06bd3c36 (ext4: fix data exposure after a crash) uncovered a
      deadlock in ext4_writepages() which was previously much harder to hit.
      After this commit xfstest generic/130 reproduces the deadlock on small
      filesystems.
      
      The problem happens when ext4_do_update_inode() sets LARGE_FILE feature
      and marks current inode handle as synchronous. That subsequently results
      in ext4_journal_stop() called from ext4_writepages() to block waiting for
      transaction commit while still holding page locks, reference to io_end,
      and some prepared bio in mpd structure each of which can possibly block
      transaction commit from completing and thus results in deadlock.
      
      Fix the problem by releasing page locks, io_end reference, and
      submitting prepared bio before calling ext4_journal_stop().
      
      [ Changed to defer the call to ext4_journal_stop() only if the handle
        is synchronous.  --tytso ]
      Reported-and-tested-by: default avatarEryu Guan <eguan@redhat.com>
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      Signed-off-by: default avatarJan Kara <jack@suse.cz>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      6e853b16
    • Vegard Nossum's avatar
      ext4: check for extents that wrap around · be6acbd7
      Vegard Nossum authored
      commit f70749ca upstream.
      
      An extent with lblock = 4294967295 and len = 1 will pass the
      ext4_valid_extent() test:
      
      	ext4_lblk_t last = lblock + len - 1;
      
      	if (len == 0 || lblock > last)
      		return 0;
      
      since last = 4294967295 + 1 - 1 = 4294967295. This would later trigger
      the BUG_ON(es->es_lblk + es->es_len < es->es_lblk) in ext4_es_end().
      
      We can simplify it by removing the - 1 altogether and changing the test
      to use lblock + len <= lblock, since now if len = 0, then lblock + 0 ==
      lblock and it fails, and if len > 0 then lblock + len > lblock in order
      to pass (i.e. it doesn't overflow).
      
      Fixes: 5946d089 ("ext4: check for overlapping extents in ext4_valid_extent_entries()")
      Fixes: 2f974865 ("ext4: check for zero length extent explicitly")
      Cc: Eryu Guan <guaneryu@gmail.com>
      Signed-off-by: default avatarPhil Turnbull <phil.turnbull@oracle.com>
      Signed-off-by: default avatarVegard Nossum <vegard.nossum@oracle.com>
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      be6acbd7
    • Herbert Xu's avatar
      crypto: scatterwalk - Fix test in scatterwalk_done · 29c8e059
      Herbert Xu authored
      commit 5f070e81 upstream.
      
      When there is more data to be processed, the current test in
      scatterwalk_done may prevent us from calling pagedone even when
      we should.
      
      In particular, if we're on an SG entry spanning multiple pages
      where the last page is not a full page, we will incorrectly skip
      calling pagedone on the second last page.
      
      This patch fixes this by adding a separate test for whether we've
      reached the end of a page.
      Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      29c8e059
    • Herbert Xu's avatar
      crypto: gcm - Filter out async ghash if necessary · 427810f9
      Herbert Xu authored
      commit b30bdfa8 upstream.
      
      As it is if you ask for a sync gcm you may actually end up with
      an async one because it does not filter out async implementations
      of ghash.
      
      This patch fixes this by adding the necessary filter when looking
      for ghash.
      Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      427810f9
    • Wei Fang's avatar
      fuse: fix wrong assignment of ->flags in fuse_send_init() · 4269a332
      Wei Fang authored
      commit 9446385f upstream.
      
      FUSE_HAS_IOCTL_DIR should be assigned to ->flags, it may be a typo.
      Signed-off-by: default avatarWei Fang <fangwei1@huawei.com>
      Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
      Fixes: 69fe05c9 ("fuse: add missing INIT flags")
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      4269a332
    • Fabian Frederick's avatar
      sysv, ipc: fix security-layer leaking · cf0483ab
      Fabian Frederick authored
      commit 9b24fef9 upstream.
      
      Commit 53dad6d3 ("ipc: fix race with LSMs") updated ipc_rcu_putref()
      to receive rcu freeing function but used generic ipc_rcu_free() instead
      of msg_rcu_free() which does security cleaning.
      
      Running LTP msgsnd06 with kmemleak gives the following:
      
        cat /sys/kernel/debug/kmemleak
      
        unreferenced object 0xffff88003c0a11f8 (size 8):
          comm "msgsnd06", pid 1645, jiffies 4294672526 (age 6.549s)
          hex dump (first 8 bytes):
            1b 00 00 00 01 00 00 00                          ........
          backtrace:
            kmemleak_alloc+0x23/0x40
            kmem_cache_alloc_trace+0xe1/0x180
            selinux_msg_queue_alloc_security+0x3f/0xd0
            security_msg_queue_alloc+0x2e/0x40
            newque+0x4e/0x150
            ipcget+0x159/0x1b0
            SyS_msgget+0x39/0x40
            entry_SYSCALL_64_fastpath+0x13/0x8f
      
      Manfred Spraul suggested to fix sem.c as well and Davidlohr Bueso to
      only use ipc_rcu_free in case of security allocation failure in newary()
      
      Fixes: 53dad6d3 ("ipc: fix race with LSMs")
      Link: http://lkml.kernel.org/r/1470083552-22966-1-git-send-email-fabf@skynet.beSigned-off-by: default avatarFabian Frederick <fabf@skynet.be>
      Cc: Davidlohr Bueso <dbueso@suse.de>
      Cc: Manfred Spraul <manfred@colorfullife.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      cf0483ab
    • Vegard Nossum's avatar
      block: fix use-after-free in seq file · 8cb3a415
      Vegard Nossum authored
      commit 77da1605 upstream.
      
      I got a KASAN report of use-after-free:
      
          ==================================================================
          BUG: KASAN: use-after-free in klist_iter_exit+0x61/0x70 at addr ffff8800b6581508
          Read of size 8 by task trinity-c1/315
          =============================================================================
          BUG kmalloc-32 (Not tainted): kasan: bad access detected
          -----------------------------------------------------------------------------
      
          Disabling lock debugging due to kernel taint
          INFO: Allocated in disk_seqf_start+0x66/0x110 age=144 cpu=1 pid=315
                  ___slab_alloc+0x4f1/0x520
                  __slab_alloc.isra.58+0x56/0x80
                  kmem_cache_alloc_trace+0x260/0x2a0
                  disk_seqf_start+0x66/0x110
                  traverse+0x176/0x860
                  seq_read+0x7e3/0x11a0
                  proc_reg_read+0xbc/0x180
                  do_loop_readv_writev+0x134/0x210
                  do_readv_writev+0x565/0x660
                  vfs_readv+0x67/0xa0
                  do_preadv+0x126/0x170
                  SyS_preadv+0xc/0x10
                  do_syscall_64+0x1a1/0x460
                  return_from_SYSCALL_64+0x0/0x6a
          INFO: Freed in disk_seqf_stop+0x42/0x50 age=160 cpu=1 pid=315
                  __slab_free+0x17a/0x2c0
                  kfree+0x20a/0x220
                  disk_seqf_stop+0x42/0x50
                  traverse+0x3b5/0x860
                  seq_read+0x7e3/0x11a0
                  proc_reg_read+0xbc/0x180
                  do_loop_readv_writev+0x134/0x210
                  do_readv_writev+0x565/0x660
                  vfs_readv+0x67/0xa0
                  do_preadv+0x126/0x170
                  SyS_preadv+0xc/0x10
                  do_syscall_64+0x1a1/0x460
                  return_from_SYSCALL_64+0x0/0x6a
      
          CPU: 1 PID: 315 Comm: trinity-c1 Tainted: G    B           4.7.0+ #62
          Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
           ffffea0002d96000 ffff880119b9f918 ffffffff81d6ce81 ffff88011a804480
           ffff8800b6581500 ffff880119b9f948 ffffffff8146c7bd ffff88011a804480
           ffffea0002d96000 ffff8800b6581500 fffffffffffffff4 ffff880119b9f970
          Call Trace:
           [<ffffffff81d6ce81>] dump_stack+0x65/0x84
           [<ffffffff8146c7bd>] print_trailer+0x10d/0x1a0
           [<ffffffff814704ff>] object_err+0x2f/0x40
           [<ffffffff814754d1>] kasan_report_error+0x221/0x520
           [<ffffffff8147590e>] __asan_report_load8_noabort+0x3e/0x40
           [<ffffffff83888161>] klist_iter_exit+0x61/0x70
           [<ffffffff82404389>] class_dev_iter_exit+0x9/0x10
           [<ffffffff81d2e8ea>] disk_seqf_stop+0x3a/0x50
           [<ffffffff8151f812>] seq_read+0x4b2/0x11a0
           [<ffffffff815f8fdc>] proc_reg_read+0xbc/0x180
           [<ffffffff814b24e4>] do_loop_readv_writev+0x134/0x210
           [<ffffffff814b4c45>] do_readv_writev+0x565/0x660
           [<ffffffff814b8a17>] vfs_readv+0x67/0xa0
           [<ffffffff814b8de6>] do_preadv+0x126/0x170
           [<ffffffff814b92ec>] SyS_preadv+0xc/0x10
      
      This problem can occur in the following situation:
      
      open()
       - pread()
          - .seq_start()
             - iter = kmalloc() // succeeds
             - seqf->private = iter
          - .seq_stop()
             - kfree(seqf->private)
       - pread()
          - .seq_start()
             - iter = kmalloc() // fails
          - .seq_stop()
             - class_dev_iter_exit(seqf->private) // boom! old pointer
      
      As the comment in disk_seqf_stop() says, stop is called even if start
      failed, so we need to reinitialise the private pointer to NULL when seq
      iteration stops.
      
      An alternative would be to set the private pointer to NULL when the
      kmalloc() in disk_seqf_start() fails.
      Signed-off-by: default avatarVegard Nossum <vegard.nossum@oracle.com>
      Acked-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      8cb3a415
    • Jason Gunthorpe's avatar
      IB/security: Restrict use of the write() interface · c96c87e1
      Jason Gunthorpe authored
      commit e6bd18f5 upstream.
      
      The drivers/infiniband stack uses write() as a replacement for
      bi-directional ioctl().  This is not safe. There are ways to
      trigger write calls that result in the return structure that
      is normally written to user space being shunted off to user
      specified kernel memory instead.
      
      For the immediate repair, detect and deny suspicious accesses to
      the write API.
      
      For long term, update the user space libraries and the kernel API
      to something that doesn't present the same security vulnerabilities
      (likely a structured ioctl() interface).
      
      The impacted uAPI interfaces are generally only available if
      hardware from drivers/infiniband is installed in the system.
      Reported-by: default avatarJann Horn <jann@thejh.net>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarJason Gunthorpe <jgunthorpe@obsidianresearch.com>
      [ Expanded check to all known write() entry points ]
      Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
      [ Expanded to include removed ipath driver, and dropped non-existent
        hfi1 driver ]
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      c96c87e1
    • James Bottomley's avatar
      scsi_lib: correctly retry failed zero length REQ_TYPE_FS commands · 4b3aa865
      James Bottomley authored
      commit a621bac3 upstream.
      
      When SCSI was written, all commands coming from the filesystem
      (REQ_TYPE_FS commands) had data.  This meant that our signal for needing
      to complete the command was the number of bytes completed being equal to
      the number of bytes in the request.  Unfortunately, with the advent of
      flush barriers, we can now get zero length REQ_TYPE_FS commands, which
      confuse this logic because they satisfy the condition every time.  This
      means they never get retried even for retryable conditions, like UNIT
      ATTENTION because we complete them early assuming they're done.  Fix
      this by special casing the early completion condition to recognise zero
      length commands with errors and let them drop through to the retry code.
      Reported-by: default avatarSebastian Parschauer <s.parschauer@gmx.de>
      Signed-off-by: default avatarJames E.J. Bottomley <jejb@linux.vnet.ibm.com>
      Tested-by: default avatarJack Wang <jinpu.wang@profitbricks.com>
      Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
      [ jwang: backport from upstream 4.7 to fix scsi resize issue ]
      Signed-off-by: default avatarJack Wang <jinpu.wang@profitbricks.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      4b3aa865
    • Christoph Hellwig's avatar
      scsi: remove scsi_end_request · 0e97a8f3
      Christoph Hellwig authored
      commit bc85dc50 upstream.
      
      By folding scsi_end_request into its only caller we can significantly clean
      up the completion logic.  We can use simple goto labels now to only have
      a single place to finish or requeue command there instead of the previous
      convoluted logic.
      Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      Reviewed-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      Reviewed-by: default avatarMike Christie <michaelc@cs.wisc.edu>
      Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
      [jwang: backport to 3.12]
      Signed-off-by: default avatarJack Wang <jinpu.wang@profitbricks.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      0e97a8f3
    • Theodore Ts'o's avatar
      random: strengthen input validation for RNDADDTOENTCNT · 25bc549d
      Theodore Ts'o authored
      commit 86a574de upstream.
      
      Don't allow RNDADDTOENTCNT or RNDADDENTROPY to accept a negative
      entropy value.  It doesn't make any sense to subtract from the entropy
      counter, and it can trigger a warning:
      
      random: negative entropy/overflow: pool input count -40000
      ------------[ cut here ]------------
      WARNING: CPU: 3 PID: 6828 at drivers/char/random.c:670[<      none
       >] credit_entropy_bits+0x21e/0xad0 drivers/char/random.c:670
      Modules linked in:
      CPU: 3 PID: 6828 Comm: a.out Not tainted 4.7.0-rc4+ #4
      Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
       ffffffff880b58e0 ffff88005dd9fcb0 ffffffff82cc838f ffffffff87158b40
       fffffbfff1016b1c 0000000000000000 0000000000000000 ffffffff87158b40
       ffffffff83283dae 0000000000000009 ffff88005dd9fcf8 ffffffff8136d27f
      Call Trace:
       [<     inline     >] __dump_stack lib/dump_stack.c:15
       [<ffffffff82cc838f>] dump_stack+0x12e/0x18f lib/dump_stack.c:51
       [<ffffffff8136d27f>] __warn+0x19f/0x1e0 kernel/panic.c:516
       [<ffffffff8136d48c>] warn_slowpath_null+0x2c/0x40 kernel/panic.c:551
       [<ffffffff83283dae>] credit_entropy_bits+0x21e/0xad0 drivers/char/random.c:670
       [<     inline     >] credit_entropy_bits_safe drivers/char/random.c:734
       [<ffffffff8328785d>] random_ioctl+0x21d/0x250 drivers/char/random.c:1546
       [<     inline     >] vfs_ioctl fs/ioctl.c:43
       [<ffffffff8185316c>] do_vfs_ioctl+0x18c/0xff0 fs/ioctl.c:674
       [<     inline     >] SYSC_ioctl fs/ioctl.c:689
       [<ffffffff8185405f>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:680
       [<ffffffff86a995c0>] entry_SYSCALL_64_fastpath+0x23/0xc1
      arch/x86/entry/entry_64.S:207
      ---[ end trace 5d4902b2ba842f1f ]---
      
      This was triggered using the test program:
      
      // autogenerated by syzkaller (http://github.com/google/syzkaller)
      
      int main() {
              int fd = open("/dev/random", O_RDWR);
              int val = -5000;
              ioctl(fd, RNDADDTOENTCNT, &val);
              return 0;
      }
      
      It's harmless in that (a) only root can trigger it, and (b) after
      complaining the code never does let the entropy count go negative, but
      it's better to simply not allow this userspace from passing in a
      negative entropy value altogether.
      
      Google-Bug-Id: #29575089
      Reported-By: default avatarDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      25bc549d
    • John Johansen's avatar