user/sven/linux.git/include, branch v4.9.43

workqueue: implicit ordered attribute should be overridable

2017-08-11T15:49:37Z

commit 0a94efb5acbb6980d7c9ab604372d93cd507e4d8 upstream. 5c0338c68706 ("workqueue: restore WQ_UNBOUND/max_active==1 to be ordered") automatically enabled ordered attribute for unbound workqueues w/ max_active == 1. Because ordered workqueues reject max_active and some attribute changes, this implicit ordered mode broke cases where the user creates an unbound workqueue w/ max_active == 1 and later explicitly changes the related attributes. This patch distinguishes explicit and implicit ordered setting and overrides from attribute changes if implict. Signed-off-by: Tejun Heo Fixes: 5c0338c68706 ("workqueue: restore WQ_UNBOUND/max_active==1 to be ordered") Cc: Holger Hoffstätte Signed-off-by: Greg Kroah-Hartman

signal: protect SIGNAL_UNKILLABLE from unintentional clearing.

2017-08-11T15:49:36Z

[ Upstream commit 2d39b3cd34e6d323720d4c61bd714f5ae202c022 ] Since commit 00cd5c37afd5 ("ptrace: permit ptracing of /sbin/init") we can now trace init processes. init is initially protected with SIGNAL_UNKILLABLE which will prevent fatal signals such as SIGSTOP, but there are a number of paths during tracing where SIGNAL_UNKILLABLE can be implicitly cleared. This can result in init becoming stoppable/killable after tracing. For example, running: while true; do kill -STOP 1; done & strace -p 1 and then stopping strace and the kill loop will result in init being left in state TASK_STOPPED. Sending SIGCONT to init will resume it, but init will now respond to future SIGSTOP signals rather than ignoring them. Make sure that when setting SIGNAL_STOP_CONTINUED/SIGNAL_STOP_STOPPED that we don't clear SIGNAL_UNKILLABLE. Link: http://lkml.kernel.org/r/20170104122017.25047-1-jamie.iles@oracle.com Signed-off-by: Jamie Iles Acked-by: Oleg Nesterov Cc: Alexander Viro Cc: Ingo Molnar Cc: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

mm, slab: make sure that KMALLOC_MAX_SIZE will fit into MAX_ORDER

2017-08-11T15:49:36Z

[ Upstream commit bb1107f7c6052c863692a41f78c000db792334bf ] Andrey Konovalov has reported the following warning triggered by the syzkaller fuzzer. WARNING: CPU: 1 PID: 9935 at mm/page_alloc.c:3511 __alloc_pages_nodemask+0x159c/0x1e20 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 9935 Comm: syz-executor0 Not tainted 4.9.0-rc7+ #34 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __alloc_pages_slowpath mm/page_alloc.c:3511 __alloc_pages_nodemask+0x159c/0x1e20 mm/page_alloc.c:3781 alloc_pages_current+0x1c7/0x6b0 mm/mempolicy.c:2072 alloc_pages include/linux/gfp.h:469 kmalloc_order+0x1f/0x70 mm/slab_common.c:1015 kmalloc_order_trace+0x1f/0x160 mm/slab_common.c:1026 kmalloc_large include/linux/slab.h:422 __kmalloc+0x210/0x2d0 mm/slub.c:3723 kmalloc include/linux/slab.h:495 ep_write_iter+0x167/0xb50 drivers/usb/gadget/legacy/inode.c:664 new_sync_write fs/read_write.c:499 __vfs_write+0x483/0x760 fs/read_write.c:512 vfs_write+0x170/0x4e0 fs/read_write.c:560 SYSC_write fs/read_write.c:607 SyS_write+0xfb/0x230 fs/read_write.c:599 entry_SYSCALL_64_fastpath+0x1f/0xc2 The issue is caused by a lack of size check for the request size in ep_write_iter which should be fixed. It, however, points to another problem, that SLUB defines KMALLOC_MAX_SIZE too large because the its KMALLOC_SHIFT_MAX is (MAX_ORDER + PAGE_SHIFT) which means that the resulting page allocator request might be MAX_ORDER which is too large (see __alloc_pages_slowpath). The same applies to the SLOB allocator which allows even larger sizes. Make sure that they are capped properly and never request more than MAX_ORDER order. Link: http://lkml.kernel.org/r/20161220130659.16461-2-mhocko@kernel.org Signed-off-by: Michal Hocko Reported-by: Andrey Konovalov Acked-by: Christoph Lameter Cc: Alexei Starovoitov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

wext: handle NULL extra data in iwe_stream_add_point better

2017-08-11T15:49:34Z

commit 93be2b74279c15c2844684b1a027fdc71dd5d9bf upstream. gcc-7 complains that wl3501_cs passes NULL into a function that then uses the argument as the input for memcpy: drivers/net/wireless/wl3501_cs.c: In function 'wl3501_get_scan': include/net/iw_handler.h:559:3: error: argument 2 null where non-null expected [-Werror=nonnull] memcpy(stream + point_len, extra, iwe->u.data.length); This works fine here because iwe->u.data.length is guaranteed to be 0 and the memcpy doesn't actually have an effect. Making the length check explicit avoids the warning and should have no other effect here. Also check the pointer itself, since otherwise we get warnings elsewhere in the code. Signed-off-by: Arnd Bergmann Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman

sctp: fix the check for _sctp_walk_params and _sctp_walk_errors

2017-08-11T15:49:33Z

[ Upstream commit 6b84202c946cd3da3a8daa92c682510e9ed80321 ] Commit b1f5bfc27a19 ("sctp: don't dereference ptr before leaving _sctp_walk_{params, errors}()") tried to fix the issue that it may overstep the chunk end for _sctp_walk_{params, errors} with 'chunk_end > offset(length) + sizeof(length)'. But it introduced a side effect: When processing INIT, it verifies the chunks with 'param.v == chunk_end' after iterating all params by sctp_walk_params(). With the check 'chunk_end > offset(length) + sizeof(length)', it would return when the last param is not yet accessed. Because the last param usually is fwdtsn supported param whose size is 4 and 'chunk_end == offset(length) + sizeof(length)' This is a badly issue even causing sctp couldn't process 4-shakes. Client would always get abort when connecting to server, due to the failure of INIT chunk verification on server. The patch is to use 'chunk_end <= offset(length) + sizeof(length)' instead of 'chunk_end < offset(length) + sizeof(length)' for both _sctp_walk_params and _sctp_walk_errors. Fixes: b1f5bfc27a19 ("sctp: don't dereference ptr before leaving _sctp_walk_{params, errors}()") Signed-off-by: Xin Long Acked-by: Neil Horman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sctp: don't dereference ptr before leaving _sctp_walk_{params, errors}()

2017-08-11T15:49:33Z

[ Upstream commit b1f5bfc27a19f214006b9b4db7b9126df2dfdf5a ] If the length field of the iterator (|pos.p| or |err|) is past the end of the chunk, we shouldn't access it. This bug has been detected by KMSAN. For the following pair of system calls: socket(PF_INET6, SOCK_STREAM, 0x84 /* IPPROTO_??? */) = 3 sendto(3, "A", 1, MSG_OOB, {sa_family=AF_INET6, sin6_port=htons(0), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=0, sin6_scope_id=0}, 28) = 1 the tool has reported a use of uninitialized memory: ================================================================== BUG: KMSAN: use of uninitialized memory in sctp_rcv+0x17b8/0x43b0 CPU: 1 PID: 2940 Comm: probe Not tainted 4.11.0-rc5+ #2926 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 dump_stack+0x172/0x1c0 lib/dump_stack.c:52 kmsan_report+0x12a/0x180 mm/kmsan/kmsan.c:927 __msan_warning_32+0x61/0xb0 mm/kmsan/kmsan_instr.c:469 __sctp_rcv_init_lookup net/sctp/input.c:1074 __sctp_rcv_lookup_harder net/sctp/input.c:1233 __sctp_rcv_lookup net/sctp/input.c:1255 sctp_rcv+0x17b8/0x43b0 net/sctp/input.c:170 sctp6_rcv+0x32/0x70 net/sctp/ipv6.c:984 ip6_input_finish+0x82f/0x1ee0 net/ipv6/ip6_input.c:279 NF_HOOK ./include/linux/netfilter.h:257 ip6_input+0x239/0x290 net/ipv6/ip6_input.c:322 dst_input ./include/net/dst.h:492 ip6_rcv_finish net/ipv6/ip6_input.c:69 NF_HOOK ./include/linux/netfilter.h:257 ipv6_rcv+0x1dbd/0x22e0 net/ipv6/ip6_input.c:203 __netif_receive_skb_core+0x2f6f/0x3a20 net/core/dev.c:4208 __netif_receive_skb net/core/dev.c:4246 process_backlog+0x667/0xba0 net/core/dev.c:4866 napi_poll net/core/dev.c:5268 net_rx_action+0xc95/0x1590 net/core/dev.c:5333 __do_softirq+0x485/0x942 kernel/softirq.c:284 do_softirq_own_stack+0x1c/0x30 arch/x86/entry/entry_64.S:902 do_softirq kernel/softirq.c:328 __local_bh_enable_ip+0x25b/0x290 kernel/softirq.c:181 local_bh_enable+0x37/0x40 ./include/linux/bottom_half.h:31 rcu_read_unlock_bh ./include/linux/rcupdate.h:931 ip6_finish_output2+0x19b2/0x1cf0 net/ipv6/ip6_output.c:124 ip6_finish_output+0x764/0x970 net/ipv6/ip6_output.c:149 NF_HOOK_COND ./include/linux/netfilter.h:246 ip6_output+0x456/0x520 net/ipv6/ip6_output.c:163 dst_output ./include/net/dst.h:486 NF_HOOK ./include/linux/netfilter.h:257 ip6_xmit+0x1841/0x1c00 net/ipv6/ip6_output.c:261 sctp_v6_xmit+0x3b7/0x470 net/sctp/ipv6.c:225 sctp_packet_transmit+0x38cb/0x3a20 net/sctp/output.c:632 sctp_outq_flush+0xeb3/0x46e0 net/sctp/outqueue.c:885 sctp_outq_uncork+0xb2/0xd0 net/sctp/outqueue.c:750 sctp_side_effects net/sctp/sm_sideeffect.c:1773 sctp_do_sm+0x6962/0x6ec0 net/sctp/sm_sideeffect.c:1147 sctp_primitive_ASSOCIATE+0x12c/0x160 net/sctp/primitive.c:88 sctp_sendmsg+0x43e5/0x4f90 net/sctp/socket.c:1954 inet_sendmsg+0x498/0x670 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:633 sock_sendmsg net/socket.c:643 SYSC_sendto+0x608/0x710 net/socket.c:1696 SyS_sendto+0x8a/0xb0 net/socket.c:1664 do_syscall_64+0xe6/0x130 arch/x86/entry/common.c:285 entry_SYSCALL64_slow_path+0x25/0x25 arch/x86/entry/entry_64.S:246 RIP: 0033:0x401133 RSP: 002b:00007fff6d99cd38 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000004002b0 RCX: 0000000000401133 RDX: 0000000000000001 RSI: 0000000000494088 RDI: 0000000000000003 RBP: 00007fff6d99cd90 R08: 00007fff6d99cd50 R09: 000000000000001c R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000004063d0 R14: 0000000000406460 R15: 0000000000000000 origin: save_stack_trace+0x37/0x40 arch/x86/kernel/stacktrace.c:59 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:302 kmsan_internal_poison_shadow+0xb1/0x1a0 mm/kmsan/kmsan.c:198 kmsan_poison_shadow+0x6d/0xc0 mm/kmsan/kmsan.c:211 slab_alloc_node mm/slub.c:2743 __kmalloc_node_track_caller+0x200/0x360 mm/slub.c:4351 __kmalloc_reserve net/core/skbuff.c:138 __alloc_skb+0x26b/0x840 net/core/skbuff.c:231 alloc_skb ./include/linux/skbuff.h:933 sctp_packet_transmit+0x31e/0x3a20 net/sctp/output.c:570 sctp_outq_flush+0xeb3/0x46e0 net/sctp/outqueue.c:885 sctp_outq_uncork+0xb2/0xd0 net/sctp/outqueue.c:750 sctp_side_effects net/sctp/sm_sideeffect.c:1773 sctp_do_sm+0x6962/0x6ec0 net/sctp/sm_sideeffect.c:1147 sctp_primitive_ASSOCIATE+0x12c/0x160 net/sctp/primitive.c:88 sctp_sendmsg+0x43e5/0x4f90 net/sctp/socket.c:1954 inet_sendmsg+0x498/0x670 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:633 sock_sendmsg net/socket.c:643 SYSC_sendto+0x608/0x710 net/socket.c:1696 SyS_sendto+0x8a/0xb0 net/socket.c:1664 do_syscall_64+0xe6/0x130 arch/x86/entry/common.c:285 return_from_SYSCALL_64+0x0/0x6a arch/x86/entry/entry_64.S:246 ================================================================== Signed-off-by: Alexander Potapenko Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

iscsi-target: Fix initial login PDU asynchronous socket close OOPs

2017-08-11T15:49:31Z

commit 25cdda95fda78d22d44157da15aa7ea34be3c804 upstream. This patch fixes a OOPs originally introduced by: commit bb048357dad6d604520c91586334c9c230366a14 Author: Nicholas Bellinger Date: Thu Sep 5 14:54:04 2013 -0700 iscsi-target: Add sk->sk_state_change to cleanup after TCP failure which would trigger a NULL pointer dereference when a TCP connection was closed asynchronously via iscsi_target_sk_state_change(), but only when the initial PDU processing in iscsi_target_do_login() from iscsi_np process context was blocked waiting for backend I/O to complete. To address this issue, this patch makes the following changes. First, it introduces some common helper functions used for checking socket closing state, checking login_flags, and atomically checking socket closing state + setting login_flags. Second, it introduces a LOGIN_FLAGS_INITIAL_PDU bit to know when a TCP connection has dropped via iscsi_target_sk_state_change(), but the initial PDU processing within iscsi_target_do_login() in iscsi_np context is still running. For this case, it sets LOGIN_FLAGS_CLOSED, but doesn't invoke schedule_delayed_work(). The original NULL pointer dereference case reported by MNC is now handled by iscsi_target_do_login() doing a iscsi_target_sk_check_close() before transitioning to FFP to determine when the socket has already closed, or iscsi_target_start_negotiation() if the login needs to exchange more PDUs (eg: iscsi_target_do_login returned 0) but the socket has closed. For both of these cases, the cleanup up of remaining connection resources will occur in iscsi_target_start_negotiation() from iscsi_np process context once the failure is detected. Finally, to handle to case where iscsi_target_sk_state_change() is called after the initial PDU procesing is complete, it now invokes conn->login_work -> iscsi_target_do_login_rx() to perform cleanup once existing iscsi_target_sk_check_close() checks detect connection failure. For this case, the cleanup of remaining connection resources will occur in iscsi_target_do_login_rx() from delayed workqueue process context once the failure is detected. Reported-by: Mike Christie Reviewed-by: Mike Christie Tested-by: Mike Christie Cc: Mike Christie Reported-by: Hannes Reinecke Cc: Hannes Reinecke Cc: Sagi Grimberg Cc: Varun Prakash Signed-off-by: Nicholas Bellinger Signed-off-by: Greg Kroah-Hartman

cpuset: fix a deadlock due to incomplete patching of cpusets_enabled()

2017-08-11T15:49:29Z

commit 89affbf5d9ebb15c6460596822e8857ea2f9e735 upstream. In codepaths that use the begin/retry interface for reading mems_allowed_seq with irqs disabled, there exists a race condition that stalls the patch process after only modifying a subset of the static_branch call sites. This problem manifested itself as a deadlock in the slub allocator, inside get_any_partial. The loop reads mems_allowed_seq value (via read_mems_allowed_begin), performs the defrag operation, and then verifies the consistency of mem_allowed via the read_mems_allowed_retry and the cookie returned by xxx_begin. The issue here is that both begin and retry first check if cpusets are enabled via cpusets_enabled() static branch. This branch can be rewritted dynamically (via cpuset_inc) if a new cpuset is created. The x86 jump label code fully synchronizes across all CPUs for every entry it rewrites. If it rewrites only one of the callsites (specifically the one in read_mems_allowed_retry) and then waits for the smp_call_function(do_sync_core) to complete while a CPU is inside the begin/retry section with IRQs off and the mems_allowed value is changed, we can hang. This is because begin() will always return 0 (since it wasn't patched yet) while retry() will test the 0 against the actual value of the seq counter. The fix is to use two different static keys: one for begin (pre_enable_key) and one for retry (enable_key). In cpuset_inc(), we first bump the pre_enable key to ensure that cpuset_mems_allowed_begin() always return a valid seqcount if are enabling cpusets. Similarly, when disabling cpusets via cpuset_dec(), we first ensure that callers of cpuset_mems_allowed_retry() will start ignoring the seqcount value before we let cpuset_mems_allowed_begin() return 0. The relevant stack traces of the two stuck threads: CPU: 1 PID: 1415 Comm: mkdir Tainted: G L 4.9.36-00104-g540c51286237 #4 Hardware name: Default string Default string/Hardware, BIOS 4.29.1-20170526215256 05/26/2017 task: ffff8817f9c28000 task.stack: ffffc9000ffa4000 RIP: smp_call_function_many+0x1f9/0x260 Call Trace: smp_call_function+0x3b/0x70 on_each_cpu+0x2f/0x90 text_poke_bp+0x87/0xd0 arch_jump_label_transform+0x93/0x100 __jump_label_update+0x77/0x90 jump_label_update+0xaa/0xc0 static_key_slow_inc+0x9e/0xb0 cpuset_css_online+0x70/0x2e0 online_css+0x2c/0xa0 cgroup_apply_control_enable+0x27f/0x3d0 cgroup_mkdir+0x2b7/0x420 kernfs_iop_mkdir+0x5a/0x80 vfs_mkdir+0xf6/0x1a0 SyS_mkdir+0xb7/0xe0 entry_SYSCALL_64_fastpath+0x18/0xad ... CPU: 2 PID: 1 Comm: init Tainted: G L 4.9.36-00104-g540c51286237 #4 Hardware name: Default string Default string/Hardware, BIOS 4.29.1-20170526215256 05/26/2017 task: ffff8818087c0000 task.stack: ffffc90000030000 RIP: int3+0x39/0x70 Call Trace: <#DB> ? ___slab_alloc+0x28b/0x5a0 ? copy_process.part.40+0xf7/0x1de0 __slab_alloc.isra.80+0x54/0x90 copy_process.part.40+0xf7/0x1de0 copy_process.part.40+0xf7/0x1de0 kmem_cache_alloc_node+0x8a/0x280 copy_process.part.40+0xf7/0x1de0 _do_fork+0xe7/0x6c0 _raw_spin_unlock_irq+0x2d/0x60 trace_hardirqs_on_caller+0x136/0x1d0 entry_SYSCALL_64_fastpath+0x5/0xad do_syscall_64+0x27/0x350 SyS_clone+0x19/0x20 do_syscall_64+0x60/0x350 entry_SYSCALL64_slow_path+0x25/0x25 Link: http://lkml.kernel.org/r/20170731040113.14197-1-dmitriyz@waymo.com Fixes: 46e700abc44c ("mm, page_alloc: remove unnecessary taking of a seqlock when cpusets are disabled") Signed-off-by: Dima Zavin Reported-by: Cliff Spradlin Acked-by: Vlastimil Babka Cc: Peter Zijlstra Cc: Christopher Lameter Cc: Li Zefan Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Cc: Mel Gorman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

mm, mprotect: flush TLB if potentially racing with a parallel reclaim leaving stale TLB entries

2017-08-11T15:49:29Z

commit 3ea277194daaeaa84ce75180ec7c7a2075027a68 upstream. Nadav Amit identified a theoritical race between page reclaim and mprotect due to TLB flushes being batched outside of the PTL being held. He described the race as follows: CPU0 CPU1 ---- ---- user accesses memory using RW PTE [PTE now cached in TLB] try_to_unmap_one() ==> ptep_get_and_clear() ==> set_tlb_ubc_flush_pending() mprotect(addr, PROT_READ) ==> change_pte_range() ==> [ PTE non-present - no flush ] user writes using cached RW PTE ... try_to_unmap_flush() The same type of race exists for reads when protecting for PROT_NONE and also exists for operations that can leave an old TLB entry behind such as munmap, mremap and madvise. For some operations like mprotect, it's not necessarily a data integrity issue but it is a correctness issue as there is a window where an mprotect that limits access still allows access. For munmap, it's potentially a data integrity issue although the race is massive as an munmap, mmap and return to userspace must all complete between the window when reclaim drops the PTL and flushes the TLB. However, it's theoritically possible so handle this issue by flushing the mm if reclaim is potentially currently batching TLB flushes. Other instances where a flush is required for a present pte should be ok as either the page lock is held preventing parallel reclaim or a page reference count is elevated preventing a parallel free leading to corruption. In the case of page_mkclean there isn't an obvious path that userspace could take advantage of without using the operations that are guarded by this patch. Other users such as gup as a race with reclaim looks just at PTEs. huge page variants should be ok as they don't race with reclaim. mincore only looks at PTEs. userfault also should be ok as if a parallel reclaim takes place, it will either fault the page back in or read some of the data before the flush occurs triggering a fault. Note that a variant of this patch was acked by Andy Lutomirski but this was for the x86 parts on top of his PCID work which didn't make the 4.13 merge window as expected. His ack is dropped from this version and there will be a follow-on patch on top of PCID that will include his ack. [akpm@linux-foundation.org: tweak comments] [akpm@linux-foundation.org: fix spello] Link: http://lkml.kernel.org/r/20170717155523.emckq2esjro6hf3z@suse.de Reported-by: Nadav Amit Signed-off-by: Mel Gorman Cc: Andy Lutomirski Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

device property: Make dev_fwnode() public

2017-08-11T15:49:29Z

commit e44bb0cbdc88686c21e2175a990b40bf6db5d005 upstream. The function to obtain a fwnode related to a struct device is useful for drivers that use the fwnode property API: it allows not being aware of the underlying firmware implementation. Signed-off-by: Sakari Ailus Reviewed-by: Mika Westerberg Signed-off-by: Rafael J. Wysocki Cc: Chris Metcalf Signed-off-by: Greg Kroah-Hartman