user/sven/linux.git, branch v4.19.63

Linux 4.19.63

2019-07-31T05:27:12Z

access: avoid the RCU grace period for the temporary subjective credentials

2019-07-31T05:27:11Z

commit d7852fbd0f0423937fa287a598bfde188bb68c22 upstream. It turns out that 'access()' (and 'faccessat()') can cause a lot of RCU work because it installs a temporary credential that gets allocated and freed for each system call. The allocation and freeing overhead is mostly benign, but because credentials can be accessed under the RCU read lock, the freeing involves a RCU grace period. Which is not a huge deal normally, but if you have a lot of access() calls, this causes a fair amount of seconday damage: instead of having a nice alloc/free patterns that hits in hot per-CPU slab caches, you have all those delayed free's, and on big machines with hundreds of cores, the RCU overhead can end up being enormous. But it turns out that all of this is entirely unnecessary. Exactly because access() only installs the credential as the thread-local subjective credential, the temporary cred pointer doesn't actually need to be RCU free'd at all. Once we're done using it, we can just free it synchronously and avoid all the RCU overhead. So add a 'non_rcu' flag to 'struct cred', which can be set by users that know they only use it in non-RCU context (there are other potential users for this). We can make it a union with the rcu freeing list head that we need for the RCU case, so this doesn't need any extra storage. Note that this also makes 'get_current_cred()' clear the new non_rcu flag, in case we have filesystems that take a long-term reference to the cred and then expect the RCU delayed freeing afterwards. It's not entirely clear that this is required, but it makes for clear semantics: the subjective cred remains non-RCU as long as you only access it synchronously using the thread-local accessors, but you _can_ use it as a generic cred if you want to. It is possible that we should just remove the whole RCU markings for ->cred entirely. Only ->real_cred is really supposed to be accessed through RCU, and the long-term cred copies that nfs uses might want to explicitly re-enable RCU freeing if required, rather than have get_current_cred() do it implicitly. But this is a "minimal semantic changes" change for the immediate problem. Acked-by: Peter Zijlstra (Intel) Acked-by: Eric Dumazet Acked-by: Paul E. McKenney Cc: Oleg Nesterov Cc: Jan Glauber Cc: Jiri Kosina Cc: Jayachandran Chandrasekharan Nair Cc: Greg KH Cc: Kees Cook Cc: David Howells Cc: Miklos Szeredi Cc: Al Viro Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

libnvdimm/bus: Stop holding nvdimm_bus_list_mutex over __nd_ioctl()

2019-07-31T05:27:11Z

commit b70d31d054ee3a6fc1034b9d7fc0ae1e481aa018 upstream. In preparation for fixing a deadlock between wait_for_bus_probe_idle() and the nvdimm_bus_list_mutex arrange for __nd_ioctl() without nvdimm_bus_list_mutex held. This also unifies the 'dimm' and 'bus' level ioctls into a common nd_ioctl() preamble implementation. Marked for -stable as it is a pre-requisite for a follow-on fix. Cc: Fixes: bf9bccc14c05 ("libnvdimm: pmem label sets and namespace instantiation") Cc: Vishal Verma Tested-by: Jane Chu Link: https://lore.kernel.org/r/156341209518.292348.7183897251740665198.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman

powerpc/tm: Fix oops on sigreturn on systems without TM

2019-07-31T05:27:11Z

commit f16d80b75a096c52354c6e0a574993f3b0dfbdfe upstream. On systems like P9 powernv where we have no TM (or P8 booted with ppc_tm=off), userspace can construct a signal context which still has the MSR TS bits set. The kernel tries to restore this context which results in the following crash: Unexpected TM Bad Thing exception at c0000000000022fc (msr 0x8000000102a03031) tm_scratch=800000020280f033 Oops: Unrecoverable exception, sig: 6 [#1] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries Modules linked in: CPU: 0 PID: 1636 Comm: sigfuz Not tainted 5.2.0-11043-g0a8ad0ffa4 #69 NIP: c0000000000022fc LR: 00007fffb2d67e48 CTR: 0000000000000000 REGS: c00000003fffbd70 TRAP: 0700 Not tainted (5.2.0-11045-g7142b497d8) MSR: 8000000102a03031 CR: 42004242 XER: 00000000 CFAR: c0000000000022e0 IRQMASK: 0 GPR00: 0000000000000072 00007fffb2b6e560 00007fffb2d87f00 0000000000000669 GPR04: 00007fffb2b6e728 0000000000000000 0000000000000000 00007fffb2b6f2a8 GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR12: 0000000000000000 00007fffb2b76900 0000000000000000 0000000000000000 GPR16: 00007fffb2370000 00007fffb2d84390 00007fffea3a15ac 000001000a250420 GPR20: 00007fffb2b6f260 0000000010001770 0000000000000000 0000000000000000 GPR24: 00007fffb2d843a0 00007fffea3a14a0 0000000000010000 0000000000800000 GPR28: 00007fffea3a14d8 00000000003d0f00 0000000000000000 00007fffb2b6e728 NIP [c0000000000022fc] rfi_flush_fallback+0x7c/0x80 LR [00007fffb2d67e48] 0x7fffb2d67e48 Call Trace: Instruction dump: e96a0220 e96a02a8 e96a0330 e96a03b8 394a0400 4200ffdc 7d2903a6 e92d0c00 e94d0c08 e96d0c10 e82d0c18 7db242a6 <4c000024> 7db243a6 7db142a6 f82d0c18 The problem is the signal code assumes TM is enabled when CONFIG_PPC_TRANSACTIONAL_MEM is enabled. This may not be the case as with P9 powernv or if `ppc_tm=off` is used on P8. This means any local user can crash the system. Fix the problem by returning a bad stack frame to the user if they try to set the MSR TS bits with sigreturn() on systems where TM is not supported. Found with sigfuz kernel selftest on P9. This fixes CVE-2019-13648. Fixes: 2b0a576d15e0 ("powerpc: Add new transactional memory state to the signal context") Cc: stable@vger.kernel.org # v3.9 Reported-by: Praveen Pandey Signed-off-by: Michael Neuling Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190719050502.405-1-mikey@neuling.org Signed-off-by: Greg Kroah-Hartman

powerpc/xive: Fix loop exit-condition in xive_find_target_in_mask()

2019-07-31T05:27:11Z

commit 4d202c8c8ed3822327285747db1765967110b274 upstream. xive_find_target_in_mask() has the following for(;;) loop which has a bug when @first == cpumask_first(@mask) and condition 1 fails to hold for every CPU in @mask. In this case we loop forever in the for-loop. first = cpu; for (;;) { if (cpu_online(cpu) && xive_try_pick_target(cpu)) // condition 1 return cpu; cpu = cpumask_next(cpu, mask); if (cpu == first) // condition 2 break; if (cpu >= nr_cpu_ids) // condition 3 cpu = cpumask_first(mask); } This is because, when @first == cpumask_first(@mask), we never hit the condition 2 (cpu == first) since prior to this check, we would have executed "cpu = cpumask_next(cpu, mask)" which will set the value of @cpu to a value greater than @first or to nr_cpus_ids. When this is coupled with the fact that condition 1 is not met, we will never exit this loop. This was discovered by the hard-lockup detector while running LTP test concurrently with SMT switch tests. watchdog: CPU 12 detected hard LOCKUP on other CPUs 68 watchdog: CPU 12 TB:85587019220796, last SMP heartbeat TB:85578827223399 (15999ms ago) watchdog: CPU 68 Hard LOCKUP watchdog: CPU 68 TB:85587019361273, last heartbeat TB:85576815065016 (19930ms ago) CPU: 68 PID: 45050 Comm: hxediag Kdump: loaded Not tainted 4.18.0-100.el8.ppc64le #1 NIP: c0000000006f5578 LR: c000000000cba9ec CTR: 0000000000000000 REGS: c000201fff3c7d80 TRAP: 0100 Not tainted (4.18.0-100.el8.ppc64le) MSR: 9000000002883033 CR: 24028424 XER: 00000000 CFAR: c0000000006f558c IRQMASK: 1 GPR00: c0000000000afc58 c000201c01c43400 c0000000015ce500 c000201cae26ec18 GPR04: 0000000000000800 0000000000000540 0000000000000800 00000000000000f8 GPR08: 0000000000000020 00000000000000a8 0000000080000000 c00800001a1beed8 GPR12: c0000000000b1410 c000201fff7f4c00 0000000000000000 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000540 0000000000000001 GPR20: 0000000000000048 0000000010110000 c00800001a1e3780 c000201cae26ed18 GPR24: 0000000000000000 c000201cae26ed8c 0000000000000001 c000000001116bc0 GPR28: c000000001601ee8 c000000001602494 c000201cae26ec18 000000000000001f NIP [c0000000006f5578] find_next_bit+0x38/0x90 LR [c000000000cba9ec] cpumask_next+0x2c/0x50 Call Trace: [c000201c01c43400] [c000201cae26ec18] 0xc000201cae26ec18 (unreliable) [c000201c01c43420] [c0000000000afc58] xive_find_target_in_mask+0x1b8/0x240 [c000201c01c43470] [c0000000000b0228] xive_pick_irq_target.isra.3+0x168/0x1f0 [c000201c01c435c0] [c0000000000b1470] xive_irq_startup+0x60/0x260 [c000201c01c43640] [c0000000001d8328] __irq_startup+0x58/0xf0 [c000201c01c43670] [c0000000001d844c] irq_startup+0x8c/0x1a0 [c000201c01c436b0] [c0000000001d57b0] __setup_irq+0x9f0/0xa90 [c000201c01c43760] [c0000000001d5aa0] request_threaded_irq+0x140/0x220 [c000201c01c437d0] [c00800001a17b3d4] bnx2x_nic_load+0x188c/0x3040 [bnx2x] [c000201c01c43950] [c00800001a187c44] bnx2x_self_test+0x1fc/0x1f70 [bnx2x] [c000201c01c43a90] [c000000000adc748] dev_ethtool+0x11d8/0x2cb0 [c000201c01c43b60] [c000000000b0b61c] dev_ioctl+0x5ac/0xa50 [c000201c01c43bf0] [c000000000a8d4ec] sock_do_ioctl+0xbc/0x1b0 [c000201c01c43c60] [c000000000a8dfb8] sock_ioctl+0x258/0x4f0 [c000201c01c43d20] [c0000000004c9704] do_vfs_ioctl+0xd4/0xa70 [c000201c01c43de0] [c0000000004ca274] sys_ioctl+0xc4/0x160 [c000201c01c43e30] [c00000000000b388] system_call+0x5c/0x70 Instruction dump: 78aad182 54a806be 3920ffff 78a50664 794a1f24 7d294036 7d43502a 7d295039 4182001c 48000034 78a9d182 79291f24 <7d23482a> 2fa90000 409e0020 38a50040 To fix this, move the check for condition 2 after the check for condition 3, so that we are able to break out of the loop soon after iterating through all the CPUs in the @mask in the problem case. Use do..while() to achieve this. Fixes: 243e25112d06 ("powerpc/xive: Native exploitation of the XIVE interrupt controller") Cc: stable@vger.kernel.org # v4.12+ Reported-by: Indira P. Joga Signed-off-by: Gautham R. Shenoy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/1563359724-13931-1-git-send-email-ego@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman

ALSA: hda - Add a conexant codec entry to let mute led work

2019-07-31T05:27:11Z

commit 3f8809499bf02ef7874254c5e23fc764a47a21a0 upstream. This conexant codec isn't in the supported codec list yet, the hda generic driver can drive this codec well, but on a Lenovo machine with mute/mic-mute leds, we need to apply CXT_FIXUP_THINKPAD_ACPI to make the leds work. After adding this codec to the list, the driver patch_conexant.c will apply THINKPAD_ACPI to this machine. Cc: stable@vger.kernel.org Signed-off-by: Hui Wang Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman

ALSA: line6: Fix wrong altsetting for LINE6_PODHD500_1

2019-07-31T05:27:11Z

commit 70256b42caaf3e13c2932c2be7903a73fbe8bb8b upstream. Commit 7b9584fa1c0b ("staging: line6: Move altsetting to properties") set a wrong altsetting for LINE6_PODHD500_1 during refactoring. Set the correct altsetting number to fix the issue. BugLink: https://bugs.launchpad.net/bugs/1790595 Fixes: 7b9584fa1c0b ("staging: line6: Move altsetting to properties") Signed-off-by: Kai-Heng Feng Cc: Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman

ALSA: ac97: Fix double free of ac97_codec_device

2019-07-31T05:27:11Z

commit 607975b30db41aad6edc846ed567191aa6b7d893 upstream. put_device will call ac97_codec_release to free ac97_codec_device and other resources, so remove the kfree and other redundant code. Fixes: 74426fbff66e ("ALSA: ac97: add an ac97 bus") Signed-off-by: Ding Xiang Cc: Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman

hpet: Fix division by zero in hpet_time_div()

2019-07-31T05:27:10Z

commit 0c7d37f4d9b8446956e97b7c5e61173cdb7c8522 upstream. The base value in do_div() called by hpet_time_div() is truncated from unsigned long to uint32_t, resulting in a divide-by-zero exception. UBSAN: Undefined behaviour in ../drivers/char/hpet.c:572:2 division by zero CPU: 1 PID: 23682 Comm: syz-executor.3 Not tainted 4.4.184.x86_64+ #4 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014 0000000000000000 b573382df1853d00 ffff8800a3287b98 ffffffff81ad7561 ffff8800a3287c00 ffffffff838b35b0 ffffffff838b3860 ffff8800a3287c20 0000000000000000 ffff8800a3287bb0 ffffffff81b8f25e ffffffff838b35a0 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x120 lib/dump_stack.c:51 [] ubsan_epilogue+0x12/0x8d lib/ubsan.c:166 [] __ubsan_handle_divrem_overflow+0x282/0x2c8 lib/ubsan.c:262 [] hpet_time_div drivers/char/hpet.c:572 [inline] [] hpet_ioctl_common drivers/char/hpet.c:663 [inline] [] hpet_ioctl_common.cold+0xa8/0xad drivers/char/hpet.c:577 [] hpet_ioctl+0xc6/0x180 drivers/char/hpet.c:676 [] vfs_ioctl fs/ioctl.c:43 [inline] [] file_ioctl fs/ioctl.c:470 [inline] [] do_vfs_ioctl+0x6e0/0xf70 fs/ioctl.c:605 [] SYSC_ioctl fs/ioctl.c:622 [inline] [] SyS_ioctl+0x94/0xc0 fs/ioctl.c:613 [] tracesys_phase2+0x90/0x95 The main C reproducer autogenerated by syzkaller, syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); memcpy((void*)0x20000100, "/dev/hpet\000", 10); syscall(__NR_openat, 0xffffffffffffff9c, 0x20000100, 0, 0); syscall(__NR_ioctl, r[0], 0x40086806, 0x40000000000000); Fix it by using div64_ul(). Signed-off-by: Kefeng Wang Signed-off-by: Zhang HongJun Cc: stable Reviewed-by: Arnd Bergmann Link: https://lore.kernel.org/r/20190711132757.130092-1-wangkefeng.wang@huawei.com Signed-off-by: Greg Kroah-Hartman

mei: me: add mule creek canyon (EHL) device ids

2019-07-31T05:27:10Z

commit 1be8624a0cbef720e8da39a15971e01abffc865b upstream. Add Mule Creek Canyon (PCH) MEI device ids for Elkhart Lake (EHL) Platform. Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Cc: stable Link: https://lore.kernel.org/r/20190712095814.20746-1-tomas.winkler@intel.com Signed-off-by: Greg Kroah-Hartman