- 15 Sep, 2017 40 commits
-
-
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: Sasha 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: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Christoph Lameter <cl@linux.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Reported-by: 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> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Jann Horn <jann@thejh.net> Acked-by: Kees 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: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg 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: Ben Hutchings <ben@decadent.org.uk>
-
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: "Jan H. Schönherr" <jschoenh@amazon.de> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [bwh: Backported to 3.2: - s/bfn/mfn/g - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: "bo Zhang" <zhangbo5891001@gmail.com> Signed-off-by: Vladis Dronov <vdronov@redhat.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: Steven 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: Ben Hutchings <ben@decadent.org.uk>
-
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: Paul 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: Ralf Baechle <ralf@linux-mips.org> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Eric Dumazet <edumazet@google.com> Cc: Jarod Wilson <jarod@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.2: only rx_dropped is updated here] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Ilya V. Matveychikov <matvejchikov@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: NeilBrown <neilb@suse.com> Cc: Ian Kent <raven@themaw.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Abdul Haleem <abdhalee@linux.vnet.ibm.com> Signed-off-by: Nicholas 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: Michael 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: Ben Hutchings <ben@decadent.org.uk>
-
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: Andrey 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: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: David Ahern <dsahern@gmail.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: David 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: Ben Hutchings <ben@decadent.org.uk>
-
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: Serhey Popovych <serhe.popovych@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
Alex Deucher authored
commit acfd6ee4 upstream. Fixes resume from suspend. bug: https://bugzilla.kernel.org/show_bug.cgi?id=196121Reported-by: Przemek <soprwa@gmail.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Daniel Drake <drake@endlessm.com> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Thomas 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: "Eric W. Biederman" <ebiederm@xmission.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Yu Zhao <yuzhao@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [bwh: Backported to 3.2: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> [bwh: Backported to 3.2: include <linux/ftrace.h>, which apparently gets included indirectly upstream] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Paul Moore <paul@paul-moore.com> Signed-off-by: James Morris <james.l.morris@oracle.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Corentin Labbe <clabbe.montjoie@gmail.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Bryant G. Ly <bryantly@linux.vnet.ibm.com> Tested-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Al Viro <viro@zeniv.linux.org.uk> [bwh: Backported to 3.2: - No functions need to be renamed - Adjust filenames, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
Al Viro authored
commit 6b0d144f upstream. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
Al Viro authored
commit 414cf718 upstream. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <james.l.morris@oracle.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Marcin Nowakowski <marcin.nowakowski@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16296/Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Moguofang <moguofang@huawei.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Guofang Mo <moguofang@huawei.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [bwh: Backported to 3.2: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: SeongJae 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: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: SeongJae 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: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
SeongJae Park authored
commit 26ddb872 upstream. This commit fixes wrong code snippets for trace_begin() and trace_end() function example definition. Signed-off-by: SeongJae 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: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: SeongJae 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: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: SeongJae 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: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: SeongJae Park <sj38.park@gmail.com> Acked-by: Masami 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: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
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: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Sinclair Yeh <syeh@vmware.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
Max Filippov authored
commit d220b942 upstream. ethoc_reset enables device interrupts, ethoc_interrupt may schedule a NAPI poll before NAPI is enabled in the ethoc_open, which results in device being unable to send or receive anything until it's closed and reopened. In case the device is flooded with ingress packets it may be unable to recover at all. Move napi_enable above ethoc_reset in the ethoc_open to fix that. Fixes: a1702857 ("net: Add support for the OpenCores 10/100 Mbps Ethernet MAC.") Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Reviewed-by: Tobias Klauser <tklauser@distanz.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-
Christophe JAILLET authored
commit 5ebb6dd3 upstream. We should ensure that 'plane_no' is '< vb->num_planes' as done in 'vb2_plane_cookie' just a few lines below. Fixes: e23ccc0a ("[media] v4l: add videobuf2 Video for Linux 2 driver framework") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> [bwh: Backported to 3.2: adjust filename, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-