1. 15 Sep, 2017 40 commits
    • Linus Torvalds's avatar
      Sanitize 'move_pages()' permission checks · a9a659c9
      Linus Torvalds authored
      commit 197e7e52 upstream.
      
      The 'move_paghes()' system call was introduced long long ago with the
      same permission checks as for sending a signal (except using
      CAP_SYS_NICE instead of CAP_SYS_KILL for the overriding capability).
      
      That turns out to not be a great choice - while the system call really
      only moves physical page allocations around (and you need other
      capabilities to do a lot of it), you can check the return value to map
      out some the virtual address choices and defeat ASLR of a binary that
      still shares your uid.
      
      So change the access checks to the more common 'ptrace_may_access()'
      model instead.
      
      This tightens the access checks for the uid, and also effectively
      changes the CAP_SYS_NICE check to CAP_SYS_PTRACE, but it's unlikely that
      anybody really _uses_ this legacy system call any more (we hav ebetter
      NUMA placement models these days), so I expect nobody to notice.
      
      Famous last words.
      Reported-by: default avatarOtto Ebeling <otto.ebeling@iki.fi>
      Acked-by: default avatarEric W. Biederman <ebiederm@xmission.com>
      Cc: Willy Tarreau <w@1wt.eu>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      [bwh: Backported to 3.2: adjust context]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      a9a659c9
    • Sasha Levin's avatar
      mm: fix NULL ptr dereference in move_pages · 125a6696
      Sasha Levin authored
      commit 6e8b09ea upstream.
      
      Commit 3268c63e ("mm: fix move/migrate_pages() race on task struct") has
      added an odd construct where 'mm' is checked for being NULL, and if it is,
      it would get dereferenced anyways by mput()ing it.
      Signed-off-by: default avatarSasha Levin <levinsasha928@gmail.com>
      Cc: Dave Hansen <dave@linux.vnet.ibm.com>
      Cc: Mel Gorman <mel@csn.ul.ie>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Cc: Hugh Dickins <hughd@google.com>
      Acked-by: default avatarChristoph Lameter <cl@linux.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 avatarBen Hutchings <ben@decadent.org.uk>
      125a6696
    • Sasha Levin's avatar
      mm: fix NULL ptr dereference in migrate_pages · d4f17eb3
      Sasha Levin authored
      commit f2a9ef88 upstream.
      
      Commit 3268c63e ("mm: fix move/migrate_pages() race on task struct") has
      added an odd construct where 'mm' is checked for being NULL, and if it is,
      it would get dereferenced anyways by mput()ing it.
      
      This would lead to the following NULL ptr deref and BUG() when calling
      migrate_pages() with a pid that has no mm struct:
      
      [25904.193704] BUG: unable to handle kernel NULL pointer dereference at 0000000000000050
      [25904.194235] IP: [<ffffffff810b0de7>] mmput+0x27/0xf0
      [25904.194235] PGD 773e6067 PUD 77da0067 PMD 0
      [25904.194235] Oops: 0002 [#1] PREEMPT SMP
      [25904.194235] CPU 2
      [25904.194235] Pid: 31608, comm: trinity Tainted: G        W    3.4.0-rc2-next-20120412-sasha #69
      [25904.194235] RIP: 0010:[<ffffffff810b0de7>]  [<ffffffff810b0de7>] mmput+0x27/0xf0
      [25904.194235] RSP: 0018:ffff880077d49e08  EFLAGS: 00010202
      [25904.194235] RAX: 0000000000000286 RBX: 0000000000000000 RCX: 0000000000000000
      [25904.194235] RDX: ffff880075ef8000 RSI: 000000000000023d RDI: 0000000000000286
      [25904.194235] RBP: ffff880077d49e18 R08: 0000000000000001 R09: 0000000000000001
      [25904.194235] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
      [25904.194235] R13: 00000000ffffffea R14: ffff880034287740 R15: ffff8800218d3010
      [25904.194235] FS:  00007fc8b244c700(0000) GS:ffff880029800000(0000) knlGS:0000000000000000
      [25904.194235] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      [25904.194235] CR2: 0000000000000050 CR3: 00000000767c6000 CR4: 00000000000406e0
      [25904.194235] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
      [25904.194235] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
      [25904.194235] Process trinity (pid: 31608, threadinfo ffff880077d48000, task ffff880075ef8000)
      [25904.194235] Stack:
      [25904.194235]  ffff8800342876c0 0000000000000000 ffff880077d49f78 ffffffff811b8020
      [25904.194235]  ffffffff811b7d91 ffff880075ef8000 ffff88002256d200 0000000000000000
      [25904.194235]  00000000000003ff 0000000000000000 0000000000000000 0000000000000000
      [25904.194235] Call Trace:
      [25904.194235]  [<ffffffff811b8020>] sys_migrate_pages+0x340/0x3a0
      [25904.194235]  [<ffffffff811b7d91>] ? sys_migrate_pages+0xb1/0x3a0
      [25904.194235]  [<ffffffff8266cbb9>] system_call_fastpath+0x16/0x1b
      [25904.194235] Code: c9 c3 66 90 55 31 d2 48 89 e5 be 3d 02 00 00 48 83 ec 10 48 89 1c 24 4c 89 64 24 08 48 89 fb 48 c7 c7 cf 0e e1 82 e8 69 18 03 00 <f0> ff 4b 50 0f 94 c0 84 c0 0f 84 aa 00 00 00 48 89 df e8 72 f1
      [25904.194235] RIP  [<ffffffff810b0de7>] mmput+0x27/0xf0
      [25904.194235]  RSP <ffff880077d49e08>
      [25904.194235] CR2: 0000000000000050
      [25904.348999] ---[ end trace a307b3ed40206b4b ]---
      Signed-off-by: default avatarSasha Levin <levinsasha928@gmail.com>
      Cc: Dave Hansen <dave@linux.vnet.ibm.com>
      Cc: Mel Gorman <mel@csn.ul.ie>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Cc: Hugh Dickins <hughd@google.com>
      Cc: Christoph Lameter <cl@linux.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 avatarBen Hutchings <ben@decadent.org.uk>
      d4f17eb3
    • Christoph Lameter's avatar
      mm: fix move/migrate_pages() race on task struct · 5e7b05a3
      Christoph Lameter authored
      commit 3268c63e upstream.
      
      Migration functions perform the rcu_read_unlock too early.  As a result
      the task pointed to may change from under us.  This can result in an oops,
      as reported by Dave Hansen in https://lkml.org/lkml/2012/2/23/302.
      
      The following patch extend the period of the rcu_read_lock until after the
      permissions checks are done.  We also take a refcount so that the task
      reference is stable when calling security check functions and performing
      cpuset node validation (which takes a mutex).
      
      The refcount is dropped before actual page migration occurs so there is no
      change to the refcounts held during page migration.
      
      Also move the determination of the mm of the task struct to immediately
      before the do_migrate*() calls so that it is clear that we switch from
      handling the task during permission checks to the mm for the actual
      migration.  Since the determination is only done once and we then no
      longer use the task_struct we can be sure that we operate on a specific
      address space that will not change from under us.
      
      [akpm@linux-foundation.org: checkpatch fixes]
      Signed-off-by: default avatarChristoph Lameter <cl@linux.com>
      Cc: "Eric W. Biederman" <ebiederm@xmission.com>
      Reported-by: default avatarDave Hansen <dave@linux.vnet.ibm.com>
      Cc: Mel Gorman <mel@csn.ul.ie>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Cc: Hugh Dickins <hughd@google.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 avatarBen Hutchings <ben@decadent.org.uk>
      5e7b05a3
    • Jann Horn's avatar
      ptrace: use fsuid, fsgid, effective creds for fs access checks · 1c8d4225
      Jann Horn authored
      commit caaee623 upstream.
      
      By checking the effective credentials instead of the real UID / permitted
      capabilities, ensure that the calling process actually intended to use its
      credentials.
      
      To ensure that all ptrace checks use the correct caller credentials (e.g.
      in case out-of-tree code or newly added code omits the PTRACE_MODE_*CREDS
      flag), use two new flags and require one of them to be set.
      
      The problem was that when a privileged task had temporarily dropped its
      privileges, e.g.  by calling setreuid(0, user_uid), with the intent to
      perform following syscalls with the credentials of a user, it still passed
      ptrace access checks that the user would not be able to pass.
      
      While an attacker should not be able to convince the privileged task to
      perform a ptrace() syscall, this is a problem because the ptrace access
      check is reused for things in procfs.
      
      In particular, the following somewhat interesting procfs entries only rely
      on ptrace access checks:
      
       /proc/$pid/stat - uses the check for determining whether pointers
           should be visible, useful for bypassing ASLR
       /proc/$pid/maps - also useful for bypassing ASLR
       /proc/$pid/cwd - useful for gaining access to restricted
           directories that contain files with lax permissions, e.g. in
           this scenario:
           lrwxrwxrwx root root /proc/13020/cwd -> /root/foobar
           drwx------ root root /root
           drwxr-xr-x root root /root/foobar
           -rw-r--r-- root root /root/foobar/secret
      
      Therefore, on a system where a root-owned mode 6755 binary changes its
      effective credentials as described and then dumps a user-specified file,
      this could be used by an attacker to reveal the memory layout of root's
      processes or reveal the contents of files he is not allowed to access
      (through /proc/$pid/cwd).
      
      [akpm@linux-foundation.org: fix warning]
      Signed-off-by: default avatarJann Horn <jann@thejh.net>
      Acked-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Casey Schaufler <casey@schaufler-ca.com>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Morris <james.l.morris@oracle.com>
      Cc: "Serge E. Hallyn" <serge.hallyn@ubuntu.com>
      Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: "Eric W. Biederman" <ebiederm@xmission.com>
      Cc: Willy Tarreau <w@1wt.eu>
      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>
      [bwh: Backported to 3.2:
       - Drop changes to kcmp, procfs map_files, procfs has_pid_permissions()
       - Keep using uid_t, gid_t and == operator for IDs
       - Adjust context]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      1c8d4225
    • Roger Pau Monne's avatar
      xen: fix bio vec merging · 33bab922
      Roger Pau Monne authored
      commit 462cdace upstream.
      
      The current test for bio vec merging is not fully accurate and can be
      tricked into merging bios when certain grant combinations are used.
      The result of these malicious bio merges is a bio that extends past
      the memory page used by any of the originating bios.
      
      Take into account the following scenario, where a guest creates two
      grant references that point to the same mfn, ie: grant 1 -> mfn A,
      grant 2 -> mfn A.
      
      These references are then used in a PV block request, and mapped by
      the backend domain, thus obtaining two different pfns that point to
      the same mfn, pfn B -> mfn A, pfn C -> mfn A.
      
      If those grants happen to be used in two consecutive sectors of a disk
      IO operation becoming two different bios in the backend domain, the
      checks in xen_biovec_phys_mergeable will succeed, because bfn1 == bfn2
      (they both point to the same mfn). However due to the bio merging,
      the backend domain will end up with a bio that expands past mfn A into
      mfn A + 1.
      
      Fix this by making sure the check in xen_biovec_phys_mergeable takes
      into account the offset and the length of the bio, this basically
      replicates whats done in __BIOVEC_PHYS_MERGEABLE using mfns (bus
      addresses). While there also remove the usage of
      __BIOVEC_PHYS_MERGEABLE, since that's already checked by the callers
      of xen_biovec_phys_mergeable.
      Reported-by: default avatar"Jan H. Schönherr" <jschoenh@amazon.de>
      Signed-off-by: default avatarRoger Pau Monné <roger.pau@citrix.com>
      Reviewed-by: default avatarJuergen Gross <jgross@suse.com>
      Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      [bwh: Backported to 3.2:
       - s/bfn/mfn/g
       - Adjust context]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      33bab922
    • Vladis Dronov's avatar
      xfrm: policy: check policy direction value · 31f11713
      Vladis Dronov authored
      commit 7bab0963 upstream.
      
      The 'dir' parameter in xfrm_migrate() is a user-controlled byte which is used
      as an array index. This can lead to an out-of-bound access, kernel lockup and
      DoS. Add a check for the 'dir' value.
      
      This fixes CVE-2017-11600.
      
      References: https://bugzilla.redhat.com/show_bug.cgi?id=1474928
      Fixes: 80c9abaa ("[XFRM]: Extension for dynamic update of endpoint address(es)")
      Reported-by: default avatar"bo Zhang" <zhangbo5891001@gmail.com>
      Signed-off-by: default avatarVladis Dronov <vdronov@redhat.com>
      Signed-off-by: default avatarSteffen Klassert <steffen.klassert@secunet.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      31f11713
    • Wei Wang's avatar
      tcp: initialize rcv_mss to TCP_MIN_MSS instead of 0 · 16a0303d
      Wei Wang authored
      commit 499350a5 upstream.
      
      When tcp_disconnect() is called, inet_csk_delack_init() sets
      icsk->icsk_ack.rcv_mss to 0.
      This could potentially cause tcp_recvmsg() => tcp_cleanup_rbuf() =>
      __tcp_select_window() call path to have division by 0 issue.
      So this patch initializes rcv_mss to TCP_MIN_MSS instead of 0.
      Reported-by: default avatarAndrey Konovalov  <andreyknvl@google.com>
      Signed-off-by: default avatarWei Wang <weiwan@google.com>
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Signed-off-by: default avatarNeal Cardwell <ncardwell@google.com>
      Signed-off-by: default avatarYuchung Cheng <ycheng@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      16a0303d
    • Sabrina Dubroca's avatar
      tracing/kprobes: Allow to create probe with a module name starting with a digit · 7903b0f9
      Sabrina Dubroca authored
      commit 9e52b325 upstream.
      
      Always try to parse an address, since kstrtoul() will safely fail when
      given a symbol as input. If that fails (which will be the case for a
      symbol), try to parse a symbol instead.
      
      This allows creating a probe such as:
      
          p:probe/vlan_gro_receive 8021q:vlan_gro_receive+0
      
      Which is necessary for this command to work:
      
          perf probe -m 8021q -a vlan_gro_receive
      
      Link: http://lkml.kernel.org/r/fd72d666f45b114e2c5b9cf7e27b91de1ec966f1.1498122881.git.sd@queasysnail.net
      
      Fixes: 413d37d1 ("tracing: Add kprobe-based event tracer")
      Acked-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
      Signed-off-by: default avatarSabrina Dubroca <sd@queasysnail.net>
      Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      [bwh: Backported to 3.2: preserve the check that an addresses isn't used for
       a kretprobe]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      7903b0f9
    • Paul Burton's avatar
      MIPS: Fix IRQ tracing & lockdep when rescheduling · 392bd6b1
      Paul Burton authored
      commit d8550860 upstream.
      
      When the scheduler sets TIF_NEED_RESCHED & we call into the scheduler
      from arch/mips/kernel/entry.S we disable interrupts. This is true
      regardless of whether we reach work_resched from syscall_exit_work,
      resume_userspace or by looping after calling schedule(). Although we
      disable interrupts in these paths we don't call trace_hardirqs_off()
      before calling into C code which may acquire locks, and we therefore
      leave lockdep with an inconsistent view of whether interrupts are
      disabled or not when CONFIG_PROVE_LOCKING & CONFIG_DEBUG_LOCKDEP are
      both enabled.
      
      Without tracing this interrupt state lockdep will print warnings such
      as the following once a task returns from a syscall via
      syscall_exit_partial with TIF_NEED_RESCHED set:
      
      [   49.927678] ------------[ cut here ]------------
      [   49.934445] WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:3687 check_flags.part.41+0x1dc/0x1e8
      [   49.946031] DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled)
      [   49.946355] CPU: 0 PID: 1 Comm: init Not tainted 4.10.0-00439-gc9fd5d362289-dirty #197
      [   49.963505] Stack : 0000000000000000 ffffffff81bb5d6a 0000000000000006 ffffffff801ce9c4
      [   49.974431]         0000000000000000 0000000000000000 0000000000000000 000000000000004a
      [   49.985300]         ffffffff80b7e487 ffffffff80a24498 a8000000ff160000 ffffffff80ede8b8
      [   49.996194]         0000000000000001 0000000000000000 0000000000000000 0000000077c8030c
      [   50.007063]         000000007fd8a510 ffffffff801cd45c 0000000000000000 a8000000ff127c88
      [   50.017945]         0000000000000000 ffffffff801cf928 0000000000000001 ffffffff80a24498
      [   50.028827]         0000000000000000 0000000000000001 0000000000000000 0000000000000000
      [   50.039688]         0000000000000000 a8000000ff127bd0 0000000000000000 ffffffff805509bc
      [   50.050575]         00000000140084e0 0000000000000000 0000000000000000 0000000000040a00
      [   50.061448]         0000000000000000 ffffffff8010e1b0 0000000000000000 ffffffff805509bc
      [   50.072327]         ...
      [   50.076087] Call Trace:
      [   50.079869] [<ffffffff8010e1b0>] show_stack+0x80/0xa8
      [   50.086577] [<ffffffff805509bc>] dump_stack+0x10c/0x190
      [   50.093498] [<ffffffff8015dde0>] __warn+0xf0/0x108
      [   50.099889] [<ffffffff8015de34>] warn_slowpath_fmt+0x3c/0x48
      [   50.107241] [<ffffffff801c15b4>] check_flags.part.41+0x1dc/0x1e8
      [   50.114961] [<ffffffff801c239c>] lock_is_held_type+0x8c/0xb0
      [   50.122291] [<ffffffff809461b8>] __schedule+0x8c0/0x10f8
      [   50.129221] [<ffffffff80946a60>] schedule+0x30/0x98
      [   50.135659] [<ffffffff80106278>] work_resched+0x8/0x34
      [   50.142397] ---[ end trace 0cb4f6ef5b99fe21 ]---
      [   50.148405] possible reason: unannotated irqs-off.
      [   50.154600] irq event stamp: 400463
      [   50.159566] hardirqs last  enabled at (400463): [<ffffffff8094edc8>] _raw_spin_unlock_irqrestore+0x40/0xa8
      [   50.171981] hardirqs last disabled at (400462): [<ffffffff8094eb98>] _raw_spin_lock_irqsave+0x30/0xb0
      [   50.183897] softirqs last  enabled at (400450): [<ffffffff8016580c>] __do_softirq+0x4ac/0x6a8
      [   50.195015] softirqs last disabled at (400425): [<ffffffff80165e78>] irq_exit+0x110/0x128
      
      Fix this by using the TRACE_IRQS_OFF macro to call trace_hardirqs_off()
      when CONFIG_TRACE_IRQFLAGS is enabled. This is done before invoking
      schedule() following the work_resched label because:
      
       1) Interrupts are disabled regardless of the path we take to reach
          work_resched() & schedule().
      
       2) Performing the tracing here avoids the need to do it in paths which
          disable interrupts but don't call out to C code before hitting a
          path which uses the RESTORE_SOME macro that will call
          trace_hardirqs_on() or trace_hardirqs_off() as appropriate.
      
      We call trace_hardirqs_on() using the TRACE_IRQS_ON macro before calling
      syscall_trace_leave() for similar reasons, ensuring that lockdep has a
      consistent view of state after we re-enable interrupts.
      Signed-off-by: default avatarPaul Burton <paul.burton@imgtec.com>
      Fixes: 1da177e4 ("Linux-2.6.12-rc2")
      Cc: linux-mips@linux-mips.org
      Patchwork: https://patchwork.linux-mips.org/patch/15385/Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
      [bwh: Backported to 3.2: adjust context]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      392bd6b1
    • Eric Dumazet's avatar
      net: prevent sign extension in dev_get_stats() · fef03f90
      Eric Dumazet authored
      commit 6f64ec74 upstream.
      
      Similar to the fix provided by Dominik Heidler in commit
      9b3dc0a1 ("l2tp: cast l2tp traffic counter to unsigned")
      we need to take care of 32bit kernels in dev_get_stats().
      
      When using atomic_long_read(), we add a 'long' to u64 and
      might misinterpret high order bit, unless we cast to unsigned.
      
      Fixes: caf586e5 ("net: add a core netdev->rx_dropped counter")
      Fixes: 015f0688 ("net: net: add a core netdev->tx_dropped counter")
      Fixes: 6e7333d3 ("net: add rx_nohandler stat counter")
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Cc: Jarod Wilson <jarod@redhat.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      [bwh: Backported to 3.2: only rx_dropped is updated here]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      fef03f90
    • Ilya Matveychikov's avatar
      lib/cmdline.c: fix get_options() overflow while parsing ranges · a9868e6e
      Ilya Matveychikov authored
      commit a91e0f68 upstream.
      
      When using get_options() it's possible to specify a range of numbers,
      like 1-100500.  The problem is that it doesn't track array size while
      calling internally to get_range() which iterates over the range and
      fills the memory with numbers.
      
      Link: http://lkml.kernel.org/r/2613C75C-B04D-4BFF-82A6-12F97BA0F620@gmail.comSigned-off-by: default avatarIlya V. Matveychikov <matvejchikov@gmail.com>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      a9868e6e
    • NeilBrown's avatar
      autofs: sanity check status reported with AUTOFS_DEV_IOCTL_FAIL · c5a12b60
      NeilBrown authored
      commit 9fa4eb8e upstream.
      
      If a positive status is passed with the AUTOFS_DEV_IOCTL_FAIL ioctl,
      autofs4_d_automount() will return
      
         ERR_PTR(status)
      
      with that status to follow_automount(), which will then dereference an
      invalid pointer.
      
      So treat a positive status the same as zero, and map to ENOENT.
      
      See comment in systemd src/core/automount.c::automount_send_ready().
      
      Link: http://lkml.kernel.org/r/871sqwczx5.fsf@notabene.neil.brown.nameSigned-off-by: default avatarNeilBrown <neilb@suse.com>
      Cc: Ian Kent <raven@themaw.net>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      c5a12b60
    • Nicholas Piggin's avatar
      powerpc/64: Initialise thread_info for emergency stacks · 7c9465d1
      Nicholas Piggin authored
      commit 34f19ff1 upstream.
      
      Emergency stacks have their thread_info mostly uninitialised, which in
      particular means garbage preempt_count values.
      
      Emergency stack code runs with interrupts disabled entirely, and is
      used very rarely, so this has been unnoticed so far. It was found by a
      proposed new powerpc watchdog that takes a soft-NMI directly from the
      masked_interrupt handler and using the emergency stack. That crashed
      at BUG_ON(in_nmi()) in nmi_enter(). preempt_count()s were found to be
      garbage.
      
      To fix this, zero the entire THREAD_SIZE allocation, and initialize
      the thread_info.
      Reported-by: default avatarAbdul Haleem <abdhalee@linux.vnet.ibm.com>
      Signed-off-by: default avatarNicholas Piggin <npiggin@gmail.com>
      [mpe: Move it all into setup_64.c, use a function not a macro. Fix
            crashes on Cell by setting preempt_count to 0 not HARDIRQ_OFFSET]
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      [bwh: Backported to 3.2:
       - There's only one emergency stack
       - No need to call klp_init_thread_info()
       - Add the ti variable in emergency_stack_init()]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      7c9465d1
    • WANG Cong's avatar
      ipv6: avoid unregistering inet6_dev for loopback · 852ea2ac
      WANG Cong authored
      commit 60abc0be upstream.
      
      The per netns loopback_dev->ip6_ptr is unregistered and set to
      NULL when its mtu is set to smaller than IPV6_MIN_MTU, this
      leads to that we could set rt->rt6i_idev NULL after a
      rt6_uncached_list_flush_dev() and then crash after another
      call.
      
      In this case we should just bring its inet6_dev down, rather
      than unregistering it, at least prior to commit 176c39af
      ("netns: fix addrconf_ifdown kernel panic") we always
      override the case for loopback.
      
      Thanks a lot to Andrey for finding a reliable reproducer.
      
      Fixes: 176c39af ("netns: fix addrconf_ifdown kernel panic")
      Reported-by: default avatarAndrey Konovalov <andreyknvl@google.com>
      Cc: Andrey Konovalov <andreyknvl@google.com>
      Cc: Daniel Lezcano <dlezcano@fr.ibm.com>
      Cc: David Ahern <dsahern@gmail.com>
      Signed-off-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
      Acked-by: default avatarDavid Ahern <dsahern@gmail.com>
      Tested-by: default avatarAndrey Konovalov <andreyknvl@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      [bwh: Backported to 3.2: the NETDEV_CHANGEMTU case used to fall-through to the
       NETDEV_DOWN case here, so replace that with a separate call to addrconf_ifdown()]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      852ea2ac
    • Serhey Popovych's avatar
      rtnetlink: add IFLA_GROUP to ifla_policy · f2a34840
      Serhey Popovych authored
      commit db833d40 upstream.
      
      Network interface groups support added while ago, however
      there is no IFLA_GROUP attribute description in policy
      and netlink message size calculations until now.
      
      Add IFLA_GROUP attribute to the policy.
      
      Fixes: cbda10fa ("net_device: add support for network device groups")
      Signed-off-by: default avatarSerhey Popovych <serhe.popovych@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      [bwh: Backported to 3.2: adjust context]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      f2a34840
    • Alex Deucher's avatar
      f7c27642
    • Daniel Drake's avatar
      Input: i8042 - add Fujitsu Lifebook AH544 to notimeout list · 9ddfcdbe
      Daniel Drake authored
      commit 817ae460 upstream.
      
      Without this quirk, the touchpad is not responsive on this product, with
      the following message repeated in the logs:
      
       psmouse serio1: bad data from KBC - timeout
      
      Add it to the notimeout list alongside other similar Fujitsu laptops.
      Signed-off-by: default avatarDaniel Drake <drake@endlessm.com>
      Signed-off-by: default avatarDmitry Torokhov <dmitry.torokhov@gmail.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      9ddfcdbe
    • Eric W. Biederman's avatar
      signal: Only reschedule timers on signals timers have sent · ee1527b6
      Eric W. Biederman authored
      commit 57db7e4a upstream.
      
      Thomas Gleixner  wrote:
      > The CRIU support added a 'feature' which allows a user space task to send
      > arbitrary (kernel) signals to itself. The changelog says:
      >
      >   The kernel prevents sending of siginfo with positive si_code, because
      >   these codes are reserved for kernel.  I think we can allow a task to
      >   send such a siginfo to itself.  This operation should not be dangerous.
      >
      > Quite contrary to that claim, it turns out that it is outright dangerous
      > for signals with info->si_code == SI_TIMER. The following code sequence in
      > a user space task allows to crash the kernel:
      >
      >    id = timer_create(CLOCK_XXX, ..... signo = SIGX);
      >    timer_set(id, ....);
      >    info->si_signo = SIGX;
      >    info->si_code = SI_TIMER:
      >    info->_sifields._timer._tid = id;
      >    info->_sifields._timer._sys_private = 2;
      >    rt_[tg]sigqueueinfo(..., SIGX, info);
      >    sigemptyset(&sigset);
      >    sigaddset(&sigset, SIGX);
      >    rt_sigtimedwait(sigset, info);
      >
      > For timers based on CLOCK_PROCESS_CPUTIME_ID, CLOCK_THREAD_CPUTIME_ID this
      > results in a kernel crash because sigwait() dequeues the signal and the
      > dequeue code observes:
      >
      >   info->si_code == SI_TIMER && info->_sifields._timer._sys_private != 0
      >
      > which triggers the following callchain:
      >
      >  do_schedule_next_timer() -> posix_cpu_timer_schedule() -> arm_timer()
      >
      > arm_timer() executes a list_add() on the timer, which is already armed via
      > the timer_set() syscall. That's a double list add which corrupts the posix
      > cpu timer list. As a consequence the kernel crashes on the next operation
      > touching the posix cpu timer list.
      >
      > Posix clocks which are internally implemented based on hrtimers are not
      > affected by this because hrtimer_start() can handle already armed timers
      > nicely, but it's a reliable way to trigger the WARN_ON() in
      > hrtimer_forward(), which complains about calling that function on an
      > already armed timer.
      
      This problem has existed since the posix timer code was merged into
      2.5.63. A few releases earlier in 2.5.60 ptrace gained the ability to
      inject not just a signal (which linux has supported since 1.0) but the
      full siginfo of a signal.
      
      The core problem is that the code will reschedule in response to
      signals getting dequeued not just for signals the timers sent but
      for other signals that happen to a si_code of SI_TIMER.
      
      Avoid this confusion by testing to see if the queued signal was
      preallocated as all timer signals are preallocated, and so far
      only the timer code preallocates signals.
      
      Move the check for if a timer needs to be rescheduled up into
      collect_signal where the preallocation check must be performed,
      and pass the result back to dequeue_signal where the code reschedules
      timers.   This makes it clear why the code cares about preallocated
      timers.
      Reported-by: default avatarThomas Gleixner <tglx@linutronix.de>
      History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
      Reference: 66dd34ad ("signal: allow to send any siginfo to itself")
      Reference: 1669ce53 ("Add PTRACE_GETSIGINFO and PTRACE_SETSIGINFO")
      Fixes: db8b50ba ("[PATCH] POSIX clocks & timers")
      Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
      [bwh: Backported to 3.2: adjust context]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      ee1527b6
    • Yu Zhao's avatar
      swap: cond_resched in swap_cgroup_prepare() · 34b2d2c4
      Yu Zhao authored
      commit ef707629 upstream.
      
      I saw need_resched() warnings when swapping on large swapfile (TBs)
      because continuously allocating many pages in swap_cgroup_prepare() took
      too long.
      
      We already cond_resched when freeing page in swap_cgroup_swapoff().  Do
      the same for the page allocation.
      
      Link: http://lkml.kernel.org/r/20170604200109.17606-1-yuzhao@google.comSigned-off-by: default avatarYu Zhao <yuzhao@google.com>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Acked-by: default avatarVladimir Davydov <vdavydov.dev@gmail.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      [bwh: Backported to 3.2: adjust filename]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      34b2d2c4
    • Naveen N. Rao's avatar
      powerpc/kprobes: Pause function_graph tracing during jprobes handling · 80f9b59c
      Naveen N. Rao authored
      commit a9f8553e upstream.
      
      This fixes a crash when function_graph and jprobes are used together.
      This is essentially commit 237d28db ("ftrace/jprobes/x86: Fix
      conflict between jprobes and function graph tracing"), but for powerpc.
      
      Jprobes breaks function_graph tracing since the jprobe hook needs to use
      jprobe_return(), which never returns back to the hook, but instead to
      the original jprobe'd function. The solution is to momentarily pause
      function_graph tracing before invoking the jprobe hook and re-enable it
      when returning back to the original jprobe'd function.
      
      Fixes: 6794c782 ("powerpc64: port of the function graph tracer")
      Signed-off-by: default avatarNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
      Acked-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
      Acked-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      [bwh: Backported to 3.2: include <linux/ftrace.h>, which apparently gets
       included indirectly upstream]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      80f9b59c
    • Dan Carpenter's avatar
      xfrm: NULL dereference on allocation failure · c8ae7519
      Dan Carpenter authored
      commit e747f643 upstream.
      
      The default error code in pfkey_msg2xfrm_state() is -ENOBUFS.  We
      added a new call to security_xfrm_state_alloc() which sets "err" to zero
      so there several places where we can return ERR_PTR(0) if kmalloc()
      fails.  The caller is expecting error pointers so it leads to a NULL
      dereference.
      
      Fixes: df71837d ("[LSM-IPSec]: Security association restriction.")
      Signed-off-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
      Signed-off-by: default avatarSteffen Klassert <steffen.klassert@secunet.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      c8ae7519
    • Dan Carpenter's avatar
      xfrm: Oops on error in pfkey_msg2xfrm_state() · f6f29764
      Dan Carpenter authored
      commit 1e3d0c2c upstream.
      
      There are some missing error codes here so we accidentally return NULL
      instead of an error pointer.  It results in a NULL pointer dereference.
      
      Fixes: df71837d ("[LSM-IPSec]: Security association restriction.")
      Signed-off-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
      Signed-off-by: default avatarSteffen Klassert <steffen.klassert@secunet.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      f6f29764
    • Paul Moore's avatar
      selinux: fix double free in selinux_parse_opts_str() · 96769d9b
      Paul Moore authored
      commit 023f108d upstream.
      
      This patch is based on a discussion generated by an earlier patch
      from Tetsuo Handa:
      
      * https://marc.info/?t=149035659300001&r=1&w=2
      
      The double free problem involves the mnt_opts field of the
      security_mnt_opts struct, selinux_parse_opts_str() frees the memory
      on error, but doesn't set the field to NULL so if the caller later
      attempts to call security_free_mnt_opts() we trigger the problem.
      
      In order to play it safe we change selinux_parse_opts_str() to call
      security_free_mnt_opts() on error instead of free'ing the memory
      directly.  This should ensure that everything is handled correctly,
      regardless of what the caller may do.
      
      Fixes: e0007529 ("LSM/SELinux: Interfaces to allow FS to control mount options")
      Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
      Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: default avatarPaul Moore <paul@paul-moore.com>
      Signed-off-by: default avatarJames Morris <james.l.morris@oracle.com>
      [bwh: Backported to 3.2: adjust context]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      96769d9b
    • Corentin Labbe's avatar
      usb: xhci: ASMedia ASM1042A chipset need shorts TX quirk · 466621f4
      Corentin Labbe authored
      commit d2f48f05 upstream.
      
      When plugging an USB webcam I see the following message:
      [106385.615559] xhci_hcd 0000:04:00.0: WARN Successful completion on short TX: needs XHCI_TRUST_TX_LENGTH quirk?
      [106390.583860] handle_tx_event: 913 callbacks suppressed
      
      With this patch applied, I get no more printing of this message.
      Signed-off-by: default avatarCorentin Labbe <clabbe.montjoie@gmail.com>
      Signed-off-by: default avatarMathias Nyman <mathias.nyman@linux.intel.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      [bwh: Backported to 3.2: adjust context]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      466621f4
    • Nicholas Bellinger's avatar
      configfs: Fix race between create_link and configfs_rmdir · 967342f4
      Nicholas Bellinger authored
      commit ba80aa90 upstream.
      
      This patch closes a long standing race in configfs between
      the creation of a new symlink in create_link(), while the
      symlink target's config_item is being concurrently removed
      via configfs_rmdir().
      
      This can happen because the symlink target's reference
      is obtained by config_item_get() in create_link() before
      the CONFIGFS_USET_DROPPING bit set by configfs_detach_prep()
      during configfs_rmdir() shutdown is actually checked..
      
      This originally manifested itself on ppc64 on v4.8.y under
      heavy load using ibmvscsi target ports with Novalink API:
      
      [ 7877.289863] rpadlpar_io: slot U8247.22L.212A91A-V1-C8 added
      [ 7879.893760] ------------[ cut here ]------------
      [ 7879.893768] WARNING: CPU: 15 PID: 17585 at ./include/linux/kref.h:46 config_item_get+0x7c/0x90 [configfs]
      [ 7879.893811] CPU: 15 PID: 17585 Comm: targetcli Tainted: G           O 4.8.17-customv2.22 #12
      [ 7879.893812] task: c00000018a0d3400 task.stack: c0000001f3b40000
      [ 7879.893813] NIP: d000000002c664ec LR: d000000002c60980 CTR: c000000000b70870
      [ 7879.893814] REGS: c0000001f3b43810 TRAP: 0700   Tainted: G O     (4.8.17-customv2.22)
      [ 7879.893815] MSR: 8000000000029033 <SF,EE,ME,IR,DR,RI,LE>  CR: 28222242  XER: 00000000
      [ 7879.893820] CFAR: d000000002c664bc SOFTE: 1
                      GPR00: d000000002c60980 c0000001f3b43a90 d000000002c70908 c0000000fbc06820
                      GPR04: c0000001ef1bd900 0000000000000004 0000000000000001 0000000000000000
                      GPR08: 0000000000000000 0000000000000001 d000000002c69560 d000000002c66d80
                      GPR12: c000000000b70870 c00000000e798700 c0000001f3b43ca0 c0000001d4949d40
                      GPR16: c00000014637e1c0 0000000000000000 0000000000000000 c0000000f2392940
                      GPR20: c0000001f3b43b98 0000000000000041 0000000000600000 0000000000000000
                      GPR24: fffffffffffff000 0000000000000000 d000000002c60be0 c0000001f1dac490
                      GPR28: 0000000000000004 0000000000000000 c0000001ef1bd900 c0000000f2392940
      [ 7879.893839] NIP [d000000002c664ec] config_item_get+0x7c/0x90 [configfs]
      [ 7879.893841] LR [d000000002c60980] check_perm+0x80/0x2e0 [configfs]
      [ 7879.893842] Call Trace:
      [ 7879.893844] [c0000001f3b43ac0] [d000000002c60980] check_perm+0x80/0x2e0 [configfs]
      [ 7879.893847] [c0000001f3b43b10] [c000000000329770] do_dentry_open+0x2c0/0x460
      [ 7879.893849] [c0000001f3b43b70] [c000000000344480] path_openat+0x210/0x1490
      [ 7879.893851] [c0000001f3b43c80] [c00000000034708c] do_filp_open+0xfc/0x170
      [ 7879.893853] [c0000001f3b43db0] [c00000000032b5bc] do_sys_open+0x1cc/0x390
      [ 7879.893856] [c0000001f3b43e30] [c000000000009584] system_call+0x38/0xec
      [ 7879.893856] Instruction dump:
      [ 7879.893858] 409d0014 38210030 e8010010 7c0803a6 4e800020 3d220000 e94981e0 892a0000
      [ 7879.893861] 2f890000 409effe0 39200001 992a0000 <0fe00000> 4bffffd0 60000000 60000000
      [ 7879.893866] ---[ end trace 14078f0b3b5ad0aa ]---
      
      To close this race, go ahead and obtain the symlink's target
      config_item reference only after the existing CONFIGFS_USET_DROPPING
      check succeeds.
      
      This way, if configfs_rmdir() wins create_link() will return -ENONET,
      and if create_link() wins configfs_rmdir() will return -EBUSY.
      Reported-by: default avatarBryant G. Ly <bryantly@linux.vnet.ibm.com>
      Tested-by: default avatarBryant G. Ly <bryantly@linux.vnet.ibm.com>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      967342f4
    • Wanpeng Li's avatar
      KVM: async_pf: avoid async pf injection when in guest mode · 86009969
      Wanpeng Li authored
      commit 9bc1f09f upstream.
      
       INFO: task gnome-terminal-:1734 blocked for more than 120 seconds.
             Not tainted 4.12.0-rc4+ #8
       "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
       gnome-terminal- D    0  1734   1015 0x00000000
       Call Trace:
        __schedule+0x3cd/0xb30
        schedule+0x40/0x90
        kvm_async_pf_task_wait+0x1cc/0x270
        ? __vfs_read+0x37/0x150
        ? prepare_to_swait+0x22/0x70
        do_async_page_fault+0x77/0xb0
        ? do_async_page_fault+0x77/0xb0
        async_page_fault+0x28/0x30
      
      This is triggered by running both win7 and win2016 on L1 KVM simultaneously,
      and then gives stress to memory on L1, I can observed this hang on L1 when
      at least ~70% swap area is occupied on L0.
      
      This is due to async pf was injected to L2 which should be injected to L1,
      L2 guest starts receiving pagefault w/ bogus %cr2(apf token from the host
      actually), and L1 guest starts accumulating tasks stuck in D state in
      kvm_async_pf_task_wait() since missing PAGE_READY async_pfs.
      
      This patch fixes the hang by doing async pf when executing L1 guest.
      
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Radim Krčmář <rkrcmar@redhat.com>
      Signed-off-by: default avatarWanpeng Li <wanpeng.li@hotmail.com>
      Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
      [bwh: Backported to 3.2: adjust context]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      86009969
    • Al Viro's avatar
      excessive checks in ufs_write_failed() and ufs_evict_inode() · 91e39600
      Al Viro authored
      commit babef37d upstream.
      
      As it is, short copy in write() to append-only file will fail
      to truncate the excessive allocated blocks.  As the matter of
      fact, all checks in ufs_truncate_blocks() are either redundant
      or wrong for that caller.  As for the only other caller
      (ufs_evict_inode()), we only need the file type checks there.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      [bwh: Backported to 3.2:
       - No functions need to be renamed
       - Adjust filenames, context]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      91e39600
    • Al Viro's avatar
      ufs: set correct ->s_maxsize · 981b7268
      Al Viro authored
      commit 6b0d144f upstream.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      [bwh: Backported to 3.2: adjust context]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      981b7268
    • Al Viro's avatar
      fix ufs_isblockset() · afb0675c
      Al Viro authored
      commit 414cf718 upstream.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      afb0675c
    • Eric Biggers's avatar
      KEYS: fix dereferencing NULL payload with nonzero length · 134a3099
      Eric Biggers authored
      commit 5649645d upstream.
      
      sys_add_key() and the KEYCTL_UPDATE operation of sys_keyctl() allowed a
      NULL payload with nonzero length to be passed to the key type's
      ->preparse(), ->instantiate(), and/or ->update() methods.  Various key
      types including asymmetric, cifs.idmap, cifs.spnego, and pkcs7_test did
      not handle this case, allowing an unprivileged user to trivially cause a
      NULL pointer dereference (kernel oops) if one of these key types was
      present.  Fix it by doing the copy_from_user() when 'plen' is nonzero
      rather than when '_payload' is non-NULL, causing the syscall to fail
      with EFAULT as expected when an invalid buffer is specified.
      Signed-off-by: default avatarEric Biggers <ebiggers@google.com>
      Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
      Signed-off-by: default avatarJames Morris <james.l.morris@oracle.com>
      [bwh: Backported to 3.2: adjust context]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      134a3099
    • Marcin Nowakowski's avatar
      MIPS: kprobes: flush_insn_slot should flush only if probe initialised · 84ffad01
      Marcin Nowakowski authored
      commit 698b8510 upstream.
      
      When ftrace is used with kprobes, it is possible for a kprobe to contain
      an invalid location (ie. only initialised to 0 and not to a specific
      location in the code). Trying to perform a cache flush on such location
      leads to a crash r4k_flush_icache_range().
      
      Fixes: c1bf207d ("MIPS: kprobe: Add support.")
      Signed-off-by: default avatarMarcin Nowakowski <marcin.nowakowski@imgtec.com>
      Cc: linux-mips@linux-mips.org
      Patchwork: https://patchwork.linux-mips.org/patch/16296/Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      84ffad01
    • Wanpeng Li's avatar
      KVM: cpuid: Fix read/write out-of-bounds vulnerability in cpuid emulation · a988c8de
      Wanpeng Li authored
      commit a3641631 upstream.
      
      If "i" is the last element in the vcpu->arch.cpuid_entries[] array, it
      potentially can be exploited the vulnerability. this will out-of-bounds
      read and write.  Luckily, the effect is small:
      
      	/* when no next entry is found, the current entry[i] is reselected */
      	for (j = i + 1; ; j = (j + 1) % nent) {
      		struct kvm_cpuid_entry2 *ej = &vcpu->arch.cpuid_entries[j];
      		if (ej->function == e->function) {
      
      It reads ej->maxphyaddr, which is user controlled.  However...
      
      			ej->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT;
      
      After cpuid_entries there is
      
      	int maxphyaddr;
      	struct x86_emulate_ctxt emulate_ctxt;  /* 16-byte aligned */
      
      So we have:
      
      - cpuid_entries at offset 1B50 (6992)
      - maxphyaddr at offset 27D0 (6992 + 3200 = 10192)
      - padding at 27D4...27DF
      - emulate_ctxt at 27E0
      
      And it writes in the padding.  Pfew, writing the ops field of emulate_ctxt
      would have been much worse.
      
      This patch fixes it by modding the index to avoid the out-of-bounds
      access. Worst case, i == j and ej->function == e->function,
      the loop can bail out.
      Reported-by: default avatarMoguofang <moguofang@huawei.com>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Radim Krčmář <rkrcmar@redhat.com>
      Cc: Guofang Mo <moguofang@huawei.com>
      Signed-off-by: default avatarWanpeng Li <wanpeng.li@hotmail.com>
      Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
      [bwh: Backported to 3.2: adjust filename]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      a988c8de
    • SeongJae Park's avatar
      perf script python: Remove dups in documentation examples · 021572e1
      SeongJae Park authored
      commit 14fc42fa upstream.
      
      Few shell command examples in perf-script-python.txt has few nitpicks
      include:
      
      - tools/perf/scripts/python directory listing command is unnecessarily
        repeated.
      - few examples contain additional information in command prompt
        unnecessarily and inconsistently.
      
      This commit fixes them to enhance readability of the document.
      Signed-off-by: default avatarSeongJae Park <sj38.park@gmail.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Tom Zanussi <tzanussi@gmail.com>
      Fixes: cff68e58 ("perf/scripts: Add perf-trace-python Documentation")
      Link: http://lkml.kernel.org/r/20170530111827.21732-4-sj38.park@gmail.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      021572e1
    • SeongJae Park's avatar
      perf script python: Updated trace_unhandled() signature · 88cf6777
      SeongJae Park authored
      commit 1bf8d5a4 upstream.
      
      Default function signature of trace_unhandled() got changed to include a
      field dict, but its documentation, perf-script-python.txt has not been
      updated.  Fix it.
      Signed-off-by: default avatarSeongJae Park <sj38.park@gmail.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Pierre Tardy <tardyp@gmail.com>
      Fixes: c0251485 ("perf scripts python: Give field dict to unhandled callback")
      Link: http://lkml.kernel.org/r/20170530111827.21732-6-sj38.park@gmail.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      88cf6777
    • SeongJae Park's avatar
      perf script python: Fix wrong code snippets in documentation · 592e51df
      SeongJae Park authored
      commit 26ddb872 upstream.
      
      This commit fixes wrong code snippets for trace_begin() and trace_end()
      function example definition.
      Signed-off-by: default avatarSeongJae Park <sj38.park@gmail.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Tom Zanussi <tzanussi@gmail.com>
      Fixes: cff68e58 ("perf/scripts: Add perf-trace-python Documentation")
      Link: http://lkml.kernel.org/r/20170530111827.21732-5-sj38.park@gmail.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      592e51df
    • SeongJae Park's avatar
      perf script: Fix documentation errors · 40e960d8
      SeongJae Park authored
      commit 34d4453d upstream.
      
      This commit fixes two errors in documents for perf-script-python and
      perf-script-perl as below:
      
      - /sys/kernel/debug/tracing events -> /sys/kernel/debug/tracing/events/
      - trace_handled -> trace_unhandled
      Signed-off-by: default avatarSeongJae Park <sj38.park@gmail.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Tom Zanussi <tzanussi@gmail.com>
      Fixes: cff68e58 ("perf/scripts: Add perf-trace-python Documentation")
      Link: http://lkml.kernel.org/r/20170530111827.21732-3-sj38.park@gmail.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      40e960d8
    • SeongJae Park's avatar
      perf script: Fix outdated comment for perf-trace-python · 809590c9
      SeongJae Park authored
      commit c76132dc upstream.
      
      Script generated by the '--gen-script' option contains an outdated
      comment. It mentions a 'perf-trace-python' document while it has been
      renamed to 'perf-script-python'. Fix it.
      Signed-off-by: default avatarSeongJae Park <sj38.park@gmail.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Fixes: 133dc4c3 ("perf: Rename 'perf trace' to 'perf script'")
      Link: http://lkml.kernel.org/r/20170530111827.21732-2-sj38.park@gmail.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      809590c9
    • SeongJae Park's avatar
      perf probe: Fix examples section of documentation · 66b7ca92
      SeongJae Park authored
      commit d89269a8 upstream.
      
      An example in perf-probe documentation for pattern of function name
      based probe addition is not providing example command for that case.
      
      This commit fixes the example to give appropriate example command.
      Signed-off-by: default avatarSeongJae Park <sj38.park@gmail.com>
      Acked-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Taeung Song <treeze.taeung@gmail.com>
      Fixes: ee391de8 ("perf probe: Update perf probe document")
      Link: http://lkml.kernel.org/r/20170507103642.30560-1-sj38.park@gmail.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      66b7ca92
    • Dan Carpenter's avatar
      drm/vmwgfx: Handle vmalloc() failure in vmw_local_fifo_reserve() · 64bf98d1
      Dan Carpenter authored
      commit f0c62e98 upstream.
      
      If vmalloc() fails then we need to a bit of cleanup before returning.
      
      Fixes: fb1d9738 ("drm/vmwgfx: Add DRM driver for VMware Virtual GPU")
      Signed-off-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
      Reviewed-by: default avatarSinclair Yeh <syeh@vmware.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      64bf98d1