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2016-04-01Linux 3.2.79v3.2.79Ben Hutchings
2016-04-01HID: usbhid: fix recursive deadlockIoan-Adrian Ratiu
commit e470127e9606b1fa151c4184243e61296d1e0c0f upstream. The critical section protected by usbhid->lock in hid_ctrl() is too big and because of this it causes a recursive deadlock. "Too big" means the case statement and the call to hid_input_report() do not need to be protected by the spinlock (no URB operations are done inside them). The deadlock happens because in certain rare cases drivers try to grab the lock while handling the ctrl irq which grabs the lock before them as described above. For example newer wacom tablets like 056a:033c try to reschedule proximity reads from wacom_intuos_schedule_prox_event() calling hid_hw_request() -> usbhid_request() -> usbhid_submit_report() which tries to grab the usbhid lock already held by hid_ctrl(). There are two ways to get out of this deadlock: 1. Make the drivers work "around" the ctrl critical region, in the wacom case for ex. by delaying the scheduling of the proximity read request itself to a workqueue. 2. Shrink the critical region so the usbhid lock protects only the instructions which modify usbhid state, calling hid_input_report() with the spinlock unlocked, allowing the device driver to grab the lock first, finish and then grab the lock afterwards in hid_ctrl(). This patch implements the 2nd solution. Signed-off-by: Ioan-Adrian Ratiu <adi@adirat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> [bwh: Backported to 3.2: adjust context] Cc: Jason Gerecke <jason.gerecke@wacom.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01include/linux/poison.h: fix LIST_POISON{1,2} offsetVasily Kulikov
commit 8a5e5e02fc83aaf67053ab53b359af08c6c49aaf upstream. Poison pointer values should be small enough to find a room in non-mmap'able/hardly-mmap'able space. E.g. on x86 "poison pointer space" is located starting from 0x0. Given unprivileged users cannot mmap anything below mmap_min_addr, it should be safe to use poison pointers lower than mmap_min_addr. The current poison pointer values of LIST_POISON{1,2} might be too big for mmap_min_addr values equal or less than 1 MB (common case, e.g. Ubuntu uses only 0x10000). There is little point to use such a big value given the "poison pointer space" below 1 MB is not yet exhausted. Changing it to a smaller value solves the problem for small mmap_min_addr setups. The values are suggested by Solar Designer: http://www.openwall.com/lists/oss-security/2015/05/02/6 Signed-off-by: Vasily Kulikov <segoon@openwall.com> Cc: Solar Designer <solar@openwall.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.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>
2016-04-01Input: aiptek - fix crash on detecting device without endpointsVladis Dronov
commit 8e20cf2bce122ce9262d6034ee5d5b76fbb92f96 upstream. The aiptek driver crashes in aiptek_probe() when a specially crafted USB device without endpoints is detected. This fix adds a check that the device has proper configuration expected by the driver. Also an error return value is changed to more matching one in one of the error paths. Reported-by: Ralf Spenneberg <ralf@spenneberg.net> Signed-off-by: Vladis Dronov <vdronov@redhat.com> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01s390/mm: four page table levels vs. forkMartin Schwidefsky
commit 3446c13b268af86391d06611327006b059b8bab1 upstream. The fork of a process with four page table levels is broken since git commit 6252d702c5311ce9 "[S390] dynamic page tables." All new mm contexts are created with three page table levels and an asce limit of 4TB. If the parent has four levels dup_mmap will add vmas to the new context which are outside of the asce limit. The subsequent call to copy_page_range will walk the three level page table structure of the new process with non-zero pgd and pud indexes. This leads to memory clobbers as the pgd_index *and* the pud_index is added to the mm->pgd pointer without a pgd_deref in between. The init_new_context() function is selecting the number of page table levels for a new context. The function is used by mm_init() which in turn is called by dup_mm() and mm_alloc(). These two are used by fork() and exec(). The init_new_context() function can distinguish the two cases by looking at mm->context.asce_limit, for fork() the mm struct has been copied and the number of page table levels may not change. For exec() the mm_alloc() function set the new mm structure to zero, in this case a three-level page table is created as the temporary stack space is located at STACK_TOP_MAX = 4TB. This fixes CVE-2016-2143. Reported-by: Marcin Kościelnicki <koriakin@0x04.net> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [bwh: Backported to 3.2: - 31-bit s390 is still supported so keep the #ifdef CONFIG_64BIT conditions - Split page table locks are not implemented for PMDs so don't call pgtable_pmd_page_{ctor,dtor}() - PMDs are not accounted so don't call mm_inc_nr_pmds() - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01Revert "drm/radeon: call hpd_irq_event on resume"Linus Torvalds
commit 256faedcfd646161477d47a1a78c32a562d2e845 upstream. This reverts commit dbb17a21c131eca94eb31136eee9a7fe5aff00d9. It turns out that commit can cause problems for systems with multiple GPUs, and causes X to hang on at least a HP Pavilion dv7 with hybrid graphics. This got noticed originally in 4.4.4, where this patch had already gotten back-ported, but 4.5-rc7 was verified to have the same problem. Alexander Deucher says: "It looks like you have a muxed system so I suspect what's happening is that one of the display is being reported as connected for both the IGP and the dGPU and then the desktop environment gets confused or there some sort problem in the detect functions since the mux is not switched to the dGPU. I don't see an easy fix unless Dave has any ideas. I'd say just revert for now" Reported-by: Jörg-Volker Peetz <jvpeetz@web.de> Acked-by: Alexander Deucher <Alexander.Deucher@amd.com> Cc: Dave Airlie <airlied@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01ubi: Fix out of bounds write in volume update codeRichard Weinberger
commit e4f6daac20332448529b11f09388f1d55ef2084c upstream. ubi_start_leb_change() allocates too few bytes. ubi_more_leb_change_data() will write up to req->upd_bytes + ubi->min_io_size bytes. Signed-off-by: Richard Weinberger <richard@nod.at> Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01MIPS: traps: Fix SIGFPE information leak from `do_ov' and `do_trap_or_bp'Maciej W. Rozycki
commit e723e3f7f9591b79e8c56b3d7c5a204a9c571b55 upstream. Avoid sending a partially initialised `siginfo_t' structure along SIGFPE signals issued from `do_ov' and `do_trap_or_bp', leading to information leaking from the kernel stack. Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> 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>
2016-04-01mld, igmp: Fix reserved tailroom calculationBenjamin Poirier
commit 1837b2e2bcd23137766555a63867e649c0b637f0 upstream. The current reserved_tailroom calculation fails to take hlen and tlen into account. skb: [__hlen__|__data____________|__tlen___|__extra__] ^ ^ head skb_end_offset In this representation, hlen + data + tlen is the size passed to alloc_skb. "extra" is the extra space made available in __alloc_skb because of rounding up by kmalloc. We can reorder the representation like so: [__hlen__|__data____________|__extra__|__tlen___] ^ ^ head skb_end_offset The maximum space available for ip headers and payload without fragmentation is min(mtu, data + extra). Therefore, reserved_tailroom = data + extra + tlen - min(mtu, data + extra) = skb_end_offset - hlen - min(mtu, skb_end_offset - hlen - tlen) = skb_tailroom - min(mtu, skb_tailroom - tlen) ; after skb_reserve(hlen) Compare the second line to the current expression: reserved_tailroom = skb_end_offset - min(mtu, skb_end_offset) and we can see that hlen and tlen are not taken into account. The min() in the third line can be expanded into: if mtu < skb_tailroom - tlen: reserved_tailroom = skb_tailroom - mtu else: reserved_tailroom = tlen Depending on hlen, tlen, mtu and the number of multicast address records, the current code may output skbs that have less tailroom than dev->needed_tailroom or it may output more skbs than needed because not all space available is used. Fixes: 4c672e4b ("ipv6: mld: fix add_grhead skb_over_panic for devs with large MTUs") Signed-off-by: Benjamin Poirier <bpoirier@suse.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> 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>
2016-04-01IB/core: Use GRH when the path hop-limit > 0Or Gerlitz
commit 11d8d645343efba0c975aefe7c2cf3b33c836c75 upstream. According to IBTA spec v1.3 section 12.7.19, QPs should use GRH when the path returned by the SA has hop-limit > 0. Currently, we do that only for the > 1 case, fix that. Fixes: 6d969a471ba1 ('IB/sa: Add ib_init_ah_from_path()') Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com> Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: Doug Ledford <dledford@redhat.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01PM / sleep / x86: Fix crash on graph trace through x86 suspendTodd E Brandt
commit 92f9e179a702a6adbc11e2fedc76ecd6ffc9e3f7 upstream. Pause/unpause graph tracing around do_suspend_lowlevel as it has inconsistent call/return info after it jumps to the wakeup vector. The graph trace buffer will otherwise become misaligned and may eventually crash and hang on suspend. To reproduce the issue and test the fix: Run a function_graph trace over suspend/resume and set the graph function to suspend_devices_and_enter. This consistently hangs the system without this fix. Signed-off-by: Todd Brandt <todd.e.brandt@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01ALSA: seq: oss: Don't drain at closing a clientTakashi Iwai
commit 197b958c1e76a575d77038cc98b4bebc2134279f upstream. The OSS sequencer client tries to drain the pending events at releasing. Unfortunately, as spotted by syzkaller fuzzer, this may lead to an unkillable process state when the event has been queued at the far future. Since the process being released can't be signaled any longer, it remains and waits for the echo-back event in that far future. Back to history, the draining feature was implemented at the time we misinterpreted POSIX definition for blocking file operation. Actually, such a behavior is superfluous at release, and we should just release the device as is instead of keeping it up forever. This patch just removes the draining call that may block the release for too long time unexpectedly. BugLink: http://lkml.kernel.org/r/CACT4Y+Y4kD-aBGj37rf-xBw9bH3GMU6P+MYg4W1e-s-paVD2pg@mail.gmail.com Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> [bwh: Backported to 3.2: snd_seq_oss_drain_write() has an extra log statement to be deleted] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01USB: serial: option: add support for Quectel UC20Yegor Yefremov
commit c0992d0f54847d0d1d85c60fcaa054f175ab1ccd upstream. Add support for Quectel UC20 and blacklist the QMI interface. Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com> [johan: amend commit message ] Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01ASoC: wm8994: Fix enum ctl accesses in a wrong typeTakashi Iwai
commit 8019c0b37cd5a87107808300a496388b777225bf upstream. The DRC Mode like "AIF1DRC1 Mode" and EQ Mode like "AIF1.1 EQ Mode" in wm8994 codec driver are enum ctls, while the current driver accesses wrongly via value.integer.value[]. They have to be via value.enumerated.item[] instead. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01ASoC: wm8958: Fix enum ctl accesses in a wrong typeTakashi Iwai
commit d0784829ae3b0beeb69b476f017d5c8a2eb95198 upstream. "MBC Mode", "VSS Mode", "VSS HPF Mode" and "Enhanced EQ Mode" ctls in wm8958 codec driver are enum, while the current driver accesses wrongly via value.integer.value[]. They have to be via value.enumerated.item[] instead. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Mark Brown <broonie@kernel.org> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01USB: cp210x: Add ID for Parrot NMEA GPS Flight RecorderVittorio Alfieri
commit 3c4c615d70c8cbdc8ba8c79ed702640930652a79 upstream. The Parrot NMEA GPS Flight Recorder is a USB composite device consisting of hub, flash storage, and cp210x usb to serial chip. It is an accessory to the mass-produced Parrot AR Drone 2. The device emits standard NMEA messages which make the it compatible with NMEA compatible software. It was tested using gpsd version 3.11-3 as an NMEA interpreter and using the official Parrot Flight Recorder. Signed-off-by: Vittorio Alfieri <vittorio88@gmail.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01ALSA: hdsp: Fix wrong boolean ctl value accessesTakashi Iwai
commit eab3c4db193f5fcccf70e884de9a922ca2c63d80 upstream. snd-hdsp driver accesses enum item values (int) instead of boolean values (long) wrongly for some ctl elements. This patch fixes them. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01ALSA: hdspm: Fix wrong boolean ctl value accessesTakashi Iwai
commit 537e48136295c5860a92138c5ea3959b9542868b upstream. snd-hdspm driver accesses enum item values (int) instead of boolean values (long) wrongly for some ctl elements. This patch fixes them. Signed-off-by: Takashi Iwai <tiwai@suse.de> [bwh: Backported to 3.2: drop change to snd_hdspm_put_system_sample_rate()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01ALSA: timer: Fix broken compat timer user status ioctlTakashi Iwai
commit 3a72494ac2a3bd229db941d51e7efe2f6ccd947b upstream. The timer user status compat ioctl returned the bogus struct used for 64bit architectures instead of the 32bit one. This patch addresses it to return the proper struct. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01hpfs: don't truncate the file when delete failsMikulas Patocka
commit b6853f78e763d42c7a158d8de3549c9827c604ab upstream. The delete opration can allocate additional space on the HPFS filesystem due to btree split. The HPFS driver checks in advance if there is available space, so that it won't corrupt the btree if we run out of space during splitting. If there is not enough available space, the HPFS driver attempted to truncate the file, but this results in a deadlock since the commit 7dd29d8d865efdb00c0542a5d2c87af8c52ea6c7 ("HPFS: Introduce a global mutex and lock it on every callback from VFS"). This patch removes the code that tries to truncate the file and -ENOSPC is returned instead. If the user hits -ENOSPC on delete, he should try to delete other files (that are stored in a leaf btree node), so that the delete operation will make some space for deleting the file stored in non-leaf btree node. Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> [bwh: Backported to 3.2: deleted code is slightly different] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01mm: thp: fix SMP race condition between THP page fault and MADV_DONTNEEDAndrea Arcangeli
commit ad33bb04b2a6cee6c1f99fabb15cddbf93ff0433 upstream. pmd_trans_unstable()/pmd_none_or_trans_huge_or_clear_bad() were introduced to locklessy (but atomically) detect when a pmd is a regular (stable) pmd or when the pmd is unstable and can infinitely transition from pmd_none() and pmd_trans_huge() from under us, while only holding the mmap_sem for reading (for writing not). While holding the mmap_sem only for reading, MADV_DONTNEED can run from under us and so before we can assume the pmd to be a regular stable pmd we need to compare it against pmd_none() and pmd_trans_huge() in an atomic way, with pmd_trans_unstable(). The old pmd_trans_huge() left a tiny window for a race. Useful applications are unlikely to notice the difference as doing MADV_DONTNEED concurrently with a page fault would lead to undefined behavior. [akpm@linux-foundation.org: tidy up comment grammar/layout] Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Reported-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.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 context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01ipr: Fix regression when loading firmwareGabriel Krisman Bertazi
commit 21b81716c6bff24cda52dc75588455f879ddbfe9 upstream. Commit d63c7dd5bcb9 ("ipr: Fix out-of-bounds null overwrite") removed the end of line handling when storing the update_fw sysfs attribute. This changed the userpace API because it started refusing writes terminated by a line feed, which broke the update tools we already have. This patch re-adds that handling, so both a write terminated by a line feed or not can make it through with the update. Fixes: d63c7dd5bcb9 ("ipr: Fix out-of-bounds null overwrite") Signed-off-by: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com> Cc: Insu Yun <wuninsu@gmail.com> Acked-by: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01ipr: Fix out-of-bounds null overwriteInsu Yun
commit d63c7dd5bcb9441af0526d370c43a65ca2c980d9 upstream. Return value of snprintf is not bound by size value, 2nd argument. (https://www.kernel.org/doc/htmldocs/kernel-api/API-snprintf.html). Return value is number of printed chars, can be larger than 2nd argument. Therefore, it can write null byte out of bounds ofbuffer. Since snprintf puts null, it does not need to put additional null byte. Signed-off-by: Insu Yun <wuninsu@gmail.com> Reviewed-by: Shane Seymour <shane.seymour@hpe.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01libata: Align ata_device's id on a cachelineHarvey Hunt
commit 4ee34ea3a12396f35b26d90a094c75db95080baa upstream. The id buffer in ata_device is a DMA target, but it isn't explicitly cacheline aligned. Due to this, adjacent fields can be overwritten with stale data from memory on non coherent architectures. As a result, the kernel is sometimes unable to communicate with an ATA device. Fix this by ensuring that the id buffer is cacheline aligned. This issue is similar to that fixed by Commit 84bda12af31f ("libata: align ap->sector_buf"). Signed-off-by: Harvey Hunt <harvey.hunt@imgtec.com> Cc: linux-kernel@vger.kernel.org Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01Fix directory hardlinks from deleted directoriesDavid Woodhouse
commit be629c62a603e5935f8177fd8a19e014100a259e upstream. When a directory is deleted, we don't take too much care about killing off all the dirents that belong to it — on the basis that on remount, the scan will conclude that the directory is dead anyway. This doesn't work though, when the deleted directory contained a child directory which was moved *out*. In the early stages of the fs build we can then end up with an apparent hard link, with the child directory appearing both in its true location, and as a child of the original directory which are this stage of the mount process we don't *yet* know is defunct. To resolve this, take out the early special-casing of the "directories shall not have hard links" rule in jffs2_build_inode_pass1(), and let the normal nlink processing happen for directories as well as other inodes. Then later in the build process we can set ic->pino_nlink to the parent inode#, as is required for directories during normal operaton, instead of the nlink. And complain only *then* about hard links which are still in evidence even after killing off all the unreachable paths. Reported-by: Liu Song <liu.song11@zte.com.cn> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01jffs2: Fix page lock / f->sem deadlockDavid Woodhouse
commit 49e91e7079febe59a20ca885a87dd1c54240d0f1 upstream. With this fix, all code paths should now be obtaining the page lock before f->sem. Reported-by: Szabó Tamás <sztomi89@gmail.com> Tested-by: Thomas Betker <thomas.betker@rohde-schwarz.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01Revert "jffs2: Fix lock acquisition order bug in jffs2_write_begin"Thomas Betker
commit 157078f64b8a9cd7011b6b900b2f2498df850748 upstream. This reverts commit 5ffd3412ae55 ("jffs2: Fix lock acquisition order bug in jffs2_write_begin"). The commit modified jffs2_write_begin() to remove a deadlock with jffs2_garbage_collect_live(), but this introduced new deadlocks found by multiple users. page_lock() actually has to be called before mutex_lock(&c->alloc_sem) or mutex_lock(&f->sem) because jffs2_write_end() and jffs2_readpage() are called with the page locked, and they acquire c->alloc_sem and f->sem, resp. In other words, the lock order in jffs2_write_begin() was correct, and it is the jffs2_garbage_collect_live() path that has to be changed. Revert the commit to get rid of the new deadlocks, and to clear the way for a better fix of the original deadlock. Reported-by: Deng Chao <deng.chao1@zte.com.cn> Reported-by: Ming Liu <liu.ming50@gmail.com> Reported-by: wangzaiwei <wangzaiwei@top-vision.cn> Signed-off-by: Thomas Betker <thomas.betker@rohde-schwarz.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> [bwh: Backported to 3.2: use D1(printk(KERN_DEBUG ...)) instead of jffs2_dbg(1, ...)] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01KVM: async_pf: do not warn on page allocation failuresChristian Borntraeger
commit d7444794a02ff655eda87e3cc54e86b940e7736f upstream. In async_pf we try to allocate with NOWAIT to get an element quickly or fail. This code also handle failures gracefully. Lets silence potential page allocation failures under load. qemu-system-s39: page allocation failure: order:0,mode:0x2200000 [...] Call Trace: ([<00000000001146b8>] show_trace+0xf8/0x148) [<000000000011476a>] show_stack+0x62/0xe8 [<00000000004a36b8>] dump_stack+0x70/0x98 [<0000000000272c3a>] warn_alloc_failed+0xd2/0x148 [<000000000027709e>] __alloc_pages_nodemask+0x94e/0xb38 [<00000000002cd36a>] new_slab+0x382/0x400 [<00000000002cf7ac>] ___slab_alloc.constprop.30+0x2dc/0x378 [<00000000002d03d0>] kmem_cache_alloc+0x160/0x1d0 [<0000000000133db4>] kvm_setup_async_pf+0x6c/0x198 [<000000000013dee8>] kvm_arch_vcpu_ioctl_run+0xd48/0xd58 [<000000000012fcaa>] kvm_vcpu_ioctl+0x372/0x690 [<00000000002f66f6>] do_vfs_ioctl+0x3be/0x510 [<00000000002f68ec>] SyS_ioctl+0xa4/0xb8 [<0000000000781c5e>] system_call+0xd6/0x264 [<000003ffa24fa06a>] 0x3ffa24fa06a Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01sunrpc/cache: fix off-by-one in qword_get()Stefan Hajnoczi
commit b7052cd7bcf3c1478796e93e3dff2b44c9e82943 upstream. The qword_get() function NUL-terminates its output buffer. If the input string is in hex format \xXXXX... and the same length as the output buffer, there is an off-by-one: int qword_get(char **bpp, char *dest, int bufsize) { ... while (len < bufsize) { ... *dest++ = (h << 4) | l; len++; } ... *dest = '\0'; return len; } This patch ensures the NUL terminator doesn't fall outside the output buffer. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01mac80211: minstrel_ht: set default tx aggregation timeout to 0Felix Fietkau
commit 7a36b930e6ed4702c866dc74a5ad07318a57c688 upstream. The value 5000 was put here with the addition of the timeout field to ieee80211_start_tx_ba_session. It was originally added in mac80211 to save resources for drivers like iwlwifi, which only supports a limited number of concurrent aggregation sessions. Since iwlwifi does not use minstrel_ht and other drivers don't need this, 0 is a better default - especially since there have been recent reports of aggregation setup related issues reproduced with ath9k. This should improve stability without causing any adverse effects. Acked-by: Avery Pennarun <apenwarr@gmail.com> Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01can: ems_usb: Fix possible tx overflowGerhard Uttenthaler
commit 90cfde46586d2286488d8ed636929e936c0c9ab2 upstream. This patch fixes the problem that more CAN messages could be sent to the interface as could be send on the CAN bus. This was more likely for slow baud rates. The sleeping _start_xmit was woken up in the _write_bulk_callback. Under heavy TX load this produced another bulk transfer without checking the free_slots variable and hence caused the overflow in the interface. Signed-off-by: Gerhard Uttenthaler <uttenthaler@ems-wuensche.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01kernel/resource.c: fix muxed resource handling in __request_region()Simon Guinot
commit 59ceeaaf355fa0fb16558ef7c24413c804932ada upstream. In __request_region, if a conflict with a BUSY and MUXED resource is detected, then the caller goes to sleep and waits for the resource to be released. A pointer on the conflicting resource is kept. At wake-up this pointer is used as a parent to retry to request the region. A first problem is that this pointer might well be invalid (if for example the conflicting resource have already been freed). Another problem is that the next call to __request_region() fails to detect a remaining conflict. The previously conflicting resource is passed as a parameter and __request_region() will look for a conflict among the children of this resource and not at the resource itself. It is likely to succeed anyway, even if there is still a conflict. Instead, the parent of the conflicting resource should be passed to __request_region(). As a fix, this patch doesn't update the parent resource pointer in the case we have to wait for a muxed region right after. Reported-and-tested-by: Vincent Pelletier <plr.vincent@gmail.com> Signed-off-by: Simon Guinot <simon.guinot@sequanux.org> Tested-by: Vincent Donnefort <vdonnefort@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01ext4: fix bh->b_state corruptionJan Kara
commit ed8ad83808f009ade97ebbf6519bc3a97fefbc0c upstream. ext4 can update bh->b_state non-atomically in _ext4_get_block() and ext4_da_get_block_prep(). Usually this is fine since bh is just a temporary storage for mapping information on stack but in some cases it can be fully living bh attached to a page. In such case non-atomic update of bh->b_state can race with an atomic update which then gets lost. Usually when we are mapping bh and thus updating bh->b_state non-atomically, nobody else touches the bh and so things work out fine but there is one case to especially worry about: ext4_finish_bio() uses BH_Uptodate_Lock on the first bh in the page to synchronize handling of PageWriteback state. So when blocksize < pagesize, we can be atomically modifying bh->b_state of a buffer that actually isn't under IO and thus can race e.g. with delalloc trying to map that buffer. The result is that we can mistakenly set / clear BH_Uptodate_Lock bit resulting in the corruption of PageWriteback state or missed unlock of BH_Uptodate_Lock. Fix the problem by always updating bh->b_state bits atomically. Reported-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu> [bwh: Backported to 3.2: - s/READ_ONCE/ACCESS_ONCE/ - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01Adding Intel Lewisburg device IDs for SATAAlexandra Yates
commit f5bdd66c705484b4bc77eb914be15c1b7881fae7 upstream. This patch complements the list of device IDs previously added for lewisburg sata. Signed-off-by: Alexandra Yates <alexandra.yates@linux.intel.com> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01USB: option: add "4G LTE usb-modem U901"Bjørn Mork
commit d061c1caa31d4d9792cfe48a2c6b309a0e01ef46 upstream. Thomas reports: T: Bus=01 Lev=01 Prnt=01 Port=03 Cnt=01 Dev#= 4 Spd=480 MxCh= 0 D: Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1 P: Vendor=05c6 ProdID=6001 Rev=00.00 S: Manufacturer=USB Modem S: Product=USB Modem S: SerialNumber=1234567890ABCDEF C: #Ifs= 5 Cfg#= 1 Atr=e0 MxPwr=500mA I: If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option I: If#= 1 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=option I: If#= 2 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option I: If#= 3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=qmi_wwan I: If#= 4 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=usb-storage Reported-by: Thomas Schäfer <tschaefer@t-online.de> Signed-off-by: Bjørn Mork <bjorn@mork.no> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01USB: cp210x: add IDs for GE B650V3 and B850V3 boardsKen Lin
commit 6627ae19385283b89356a199d7f03c75ba35fb29 upstream. Add USB ID for cp2104/5 devices on GE B650v3 and B850v3 boards. Signed-off-by: Ken Lin <ken.lin@advantech.com.tw> Signed-off-by: Akshay Bhat <akshay.bhat@timesys.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01USB: option: add support for SIM7100EAndrey Skvortsov
commit 3158a8d416f4e1b79dcc867d67cb50013140772c upstream. $ lsusb: Bus 001 Device 101: ID 1e0e:9001 Qualcomm / Option $ usb-devices: T: Bus=01 Lev=02 Prnt=02 Port=00 Cnt=01 Dev#=101 Spd=480 MxCh= 0 D: Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs= 2 P: Vendor=1e0e ProdID=9001 Rev= 2.32 S: Manufacturer=SimTech, Incorporated S: Product=SimTech, Incorporated S: SerialNumber=0123456789ABCDEF C:* #Ifs= 7 Cfg#= 1 Atr=80 MxPwr=500mA I:* If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option I:* If#= 1 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option I:* If#= 2 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option I:* If#= 3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option I:* If#= 4 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option I:* If#= 5 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=qmi_wwan I:* If#= 6 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=42 Prot=01 Driver=(none) The last interface (6) is used for Android Composite ADB interface. Serial port layout: 0: QCDM/DIAG 1: NMEA 2: AT 3: AT/PPP 4: audio Signed-off-by: Andrey Skvortsov <andrej.skvortzov@gmail.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01net/mlx4_en: Count HW buffer overrun only onceAmir Vadai
commit 281e8b2fdf8e4ef366b899453cae50e09b577ada upstream. RdropOvflw counts overrun of HW buffer, therefore should be used for rx_fifo_errors only. Currently RdropOvflw counter is mistakenly also set into rx_missed_errors and rx_over_errors too, which makes the device total dropped packets accounting to show wrong results. Fix that. Use it for rx_fifo_errors only. Fixes: c27a02cd94d6 ('mlx4_en: Add driver for Mellanox ConnectX 10GbE NIC') Signed-off-by: Amir Vadai <amir@vadai.me> Signed-off-by: Eugenia Emantayev <eugenia@mellanox.com> Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01usb: dwc3: Fix assignment of EP transfer resourcesJohn Youn
commit c450960187f45d4260db87c7dd4fc0bceb5565d8 upstream. The assignement of EP transfer resources was not handled properly in the dwc3 driver. Commit aebda6187181 ("usb: dwc3: Reset the transfer resource index on SET_INTERFACE") previously fixed one aspect of this where resources may be exhausted with multiple calls to SET_INTERFACE. However, it introduced an issue where composite devices with multiple interfaces can be assigned the same transfer resources for different endpoints. This patch solves both issues. The assignment of transfer resources cannot perfectly follow the data book due to the fact that the controller driver does not have all knowledge of the configuration in advance. It is given this information piecemeal by the composite gadget framework after every SET_CONFIGURATION and SET_INTERFACE. Trying to follow the databook programming model in this scenario can cause errors. For two reasons: 1) The databook says to do DEPSTARTCFG for every SET_CONFIGURATION and SET_INTERFACE (8.1.5). This is incorrect in the scenario of multiple interfaces. 2) The databook does not mention doing more DEPXFERCFG for new endpoint on alt setting (8.1.6). The following simplified method is used instead: All hardware endpoints can be assigned a transfer resource and this setting will stay persistent until either a core reset or hibernation. So whenever we do a DEPSTARTCFG(0) we can go ahead and do DEPXFERCFG for every hardware endpoint as well. We are guaranteed that there are as many transfer resources as endpoints. This patch triggers off of the calling dwc3_gadget_start_config() for EP0-out, which always happens first, and which should only happen in one of the above conditions. Fixes: aebda6187181 ("usb: dwc3: Reset the transfer resource index on SET_INTERFACE") Reported-by: Ravi Babu <ravibabu@ti.com> Signed-off-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Felipe Balbi <balbi@kernel.org> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01x86/uaccess/64: Handle the caching of 4-byte nocache copies properly in ↵Toshi Kani
__copy_user_nocache() commit a82eee7424525e34e98d821dd059ce14560a1e35 upstream. Data corruption issues were observed in tests which initiated a system crash/reset while accessing BTT devices. This problem is reproducible. The BTT driver calls pmem_rw_bytes() to update data in pmem devices. This interface calls __copy_user_nocache(), which uses non-temporal stores so that the stores to pmem are persistent. __copy_user_nocache() uses non-temporal stores when a request size is 8 bytes or larger (and is aligned by 8 bytes). The BTT driver updates the BTT map table, which entry size is 4 bytes. Therefore, updates to the map table entries remain cached, and are not written to pmem after a crash. Change __copy_user_nocache() to use non-temporal store when a request size is 4 bytes. The change extends the current byte-copy path for a less-than-8-bytes request, and does not add any overhead to the regular path. Reported-and-tested-by: Micah Parrish <micah.parrish@hpe.com> Reported-and-tested-by: Brian Boylston <brian.boylston@hpe.com> Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: linux-nvdimm@lists.01.org Link: http://lkml.kernel.org/r/1455225857-12039-3-git-send-email-toshi.kani@hpe.com [ Small readability edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> [bwh: Backported to 3.2: aadjust filename, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01x86/uaccess/64: Make the __copy_user_nocache() assembly code more readableToshi Kani
commit ee9737c924706aaa72c2ead93e3ad5644681dc1c upstream. Add comments to __copy_user_nocache() to clarify its procedures and alignment requirements. Also change numeric branch target labels to named local labels. No code changed: arch/x86/lib/copy_user_64.o: text data bss dec hex filename 1239 0 0 1239 4d7 copy_user_64.o.before 1239 0 0 1239 4d7 copy_user_64.o.after md5: 58bed94c2db98c1ca9a2d46d0680aaae copy_user_64.o.before.asm 58bed94c2db98c1ca9a2d46d0680aaae copy_user_64.o.after.asm Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: brian.boylston@hpe.com Cc: dan.j.williams@intel.com Cc: linux-nvdimm@lists.01.org Cc: micah.parrish@hpe.com Cc: ross.zwisler@linux.intel.com Cc: vishal.l.verma@intel.com Link: http://lkml.kernel.org/r/1455225857-12039-2-git-send-email-toshi.kani@hpe.com [ Small readability edits and added object file comparison. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> [bwh: Backported to 3.2: aadjust filename, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01x86, extable: Remove open-coded exception table entries in ↵H. Peter Anvin
arch/x86/lib/copy_user_nocache_64.S commit 0d8559feafbc9dc5a2c17ba42aea7de824b18308 upstream. Remove open-coded exception table entries in arch/x86/lib/copy_user_nocache_64.S, and replace them with _ASM_EXTABLE() macros; this will allow us to change the format and type of the exception table entries. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: David Daney <david.daney@cavium.com> Link: http://lkml.kernel.org/r/CA%2B55aFyijf43qSu3N9nWHEBwaGbb7T2Oq9A=9EyR=Jtyqfq_cQ@mail.gmail.com Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01af_unix: Guard against other == sk in unix_dgram_sendmsgRainer Weikusat
commit a5527dda344fff0514b7989ef7a755729769daa1 upstream. The unix_dgram_sendmsg routine use the following test if (unlikely(unix_peer(other) != sk && unix_recvq_full(other))) { to determine if sk and other are in an n:1 association (either established via connect or by using sendto to send messages to an unrelated socket identified by address). This isn't correct as the specified address could have been bound to the sending socket itself or because this socket could have been connected to itself by the time of the unix_peer_get but disconnected before the unix_state_lock(other). In both cases, the if-block would be entered despite other == sk which might either block the sender unintentionally or lead to trying to unlock the same spin lock twice for a non-blocking send. Add a other != sk check to guard against this. Fixes: 7d267278a9ec ("unix: avoid use-after-free in ep_remove_wait_queue") Reported-By: Philipp Hahn <pmhahn@pmhahn.de> Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com> Tested-by: Philipp Hahn <pmhahn@pmhahn.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01af_unix: Don't set err in unix_stream_read_generic unless there was an errorRainer Weikusat
commit 1b92ee3d03af6643df395300ba7748f19ecdb0c5 upstream. The present unix_stream_read_generic contains various code sequences of the form err = -EDISASTER; if (<test>) goto out; This has the unfortunate side effect of possibly causing the error code to bleed through to the final out: return copied ? : err; and then to be wrongly returned if no data was copied because the caller didn't supply a data buffer, as demonstrated by the program available at http://pad.lv/1540731 Change it such that err is only set if an error condition was detected. Fixes: 3822b5c2fc62 ("af_unix: Revert 'lock_interruptible' in stream receive code") Reported-by: Joseph Salisbury <joseph.salisbury@canonical.com> Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.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>
2016-04-01ALSA: seq: Fix double port list deletionTakashi Iwai
commit 13d5e5d4725c64ec06040d636832e78453f477b7 upstream. The commit [7f0973e973cd: ALSA: seq: Fix lockdep warnings due to double mutex locks] split the management of two linked lists (source and destination) into two individual calls for avoiding the AB/BA deadlock. However, this may leave the possible double deletion of one of two lists when the counterpart is being deleted concurrently. It ends up with a list corruption, as revealed by syzkaller fuzzer. This patch fixes it by checking the list emptiness and skipping the deletion and the following process. BugLink: http://lkml.kernel.org/r/CACT4Y+bay9qsrz6dQu31EcGaH9XwfW7o3oBzSQUG9fMszoh=Sg@mail.gmail.com Fixes: 7f0973e973cd ('ALSA: seq: Fix lockdep warnings due to 'double mutex locks) Reported-by: Dmitry Vyukov <dvyukov@google.com> Tested-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01tracing: Fix freak link error caused by branch tracerArnd Bergmann
commit b33c8ff4431a343561e2319f17c14286f2aa52e2 upstream. In my randconfig tests, I came across a bug that involves several components: * gcc-4.9 through at least 5.3 * CONFIG_GCOV_PROFILE_ALL enabling -fprofile-arcs for all files * CONFIG_PROFILE_ALL_BRANCHES overriding every if() * The optimized implementation of do_div() that tries to replace a library call with an division by multiplication * code in drivers/media/dvb-frontends/zl10353.c doing u32 adc_clock = 450560; /* 45.056 MHz */ if (state->config.adc_clock) adc_clock = state->config.adc_clock; do_div(value, adc_clock); In this case, gcc fails to determine whether the divisor in do_div() is __builtin_constant_p(). In particular, it concludes that __builtin_constant_p(adc_clock) is false, while __builtin_constant_p(!!adc_clock) is true. That in turn throws off the logic in do_div() that also uses __builtin_constant_p(), and instead of picking either the constant- optimized division, and the code in ilog2() that uses __builtin_constant_p() to figure out whether it knows the answer at compile time. The result is a link error from failing to find multiple symbols that should never have been called based on the __builtin_constant_p(): dvb-frontends/zl10353.c:138: undefined reference to `____ilog2_NaN' dvb-frontends/zl10353.c:138: undefined reference to `__aeabi_uldivmod' ERROR: "____ilog2_NaN" [drivers/media/dvb-frontends/zl10353.ko] undefined! ERROR: "__aeabi_uldivmod" [drivers/media/dvb-frontends/zl10353.ko] undefined! This patch avoids the problem by changing __trace_if() to check whether the condition is known at compile-time to be nonzero, rather than checking whether it is actually a constant. I see this one link error in roughly one out of 1600 randconfig builds on ARM, and the patch fixes all known instances. Link: http://lkml.kernel.org/r/1455312410-1058841-1-git-send-email-arnd@arndb.de Acked-by: Nicolas Pitre <nico@linaro.org> Fixes: ab3c9c686e22 ("branch tracer, intel-iommu: fix build with CONFIG_BRANCH_TRACER=y") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01tracepoints: Do not trace when cpu is offlineSteven Rostedt (Red Hat)
commit f37755490fe9bf76f6ba1d8c6591745d3574a6a6 upstream. The tracepoint infrastructure uses RCU sched protection to enable and disable tracepoints safely. There are some instances where tracepoints are used in infrastructure code (like kfree()) that get called after a CPU is going offline, and perhaps when it is coming back online but hasn't been registered yet. This can probuce the following warning: [ INFO: suspicious RCU usage. ] 4.4.0-00006-g0fe53e8-dirty #34 Tainted: G S ------------------------------- include/trace/events/kmem.h:141 suspicious rcu_dereference_check() usage! other info that might help us debug this: RCU used illegally from offline CPU! rcu_scheduler_active = 1, debug_locks = 1 no locks held by swapper/8/0. stack backtrace: CPU: 8 PID: 0 Comm: swapper/8 Tainted: G S 4.4.0-00006-g0fe53e8-dirty #34 Call Trace: [c0000005b76c78d0] [c0000000008b9540] .dump_stack+0x98/0xd4 (unreliable) [c0000005b76c7950] [c00000000010c898] .lockdep_rcu_suspicious+0x108/0x170 [c0000005b76c79e0] [c00000000029adc0] .kfree+0x390/0x440 [c0000005b76c7a80] [c000000000055f74] .destroy_context+0x44/0x100 [c0000005b76c7b00] [c0000000000934a0] .__mmdrop+0x60/0x150 [c0000005b76c7b90] [c0000000000e3ff0] .idle_task_exit+0x130/0x140 [c0000005b76c7c20] [c000000000075804] .pseries_mach_cpu_die+0x64/0x310 [c0000005b76c7cd0] [c000000000043e7c] .cpu_die+0x3c/0x60 [c0000005b76c7d40] [c0000000000188d8] .arch_cpu_idle_dead+0x28/0x40 [c0000005b76c7db0] [c000000000101e6c] .cpu_startup_entry+0x50c/0x560 [c0000005b76c7ed0] [c000000000043bd8] .start_secondary+0x328/0x360 [c0000005b76c7f90] [c000000000008a6c] start_secondary_prolog+0x10/0x14 This warning is not a false positive either. RCU is not protecting code that is being executed while the CPU is offline. Instead of playing "whack-a-mole(TM)" and adding conditional statements to the tracepoints we find that are used in this instance, simply add a cpu_online() test to the tracepoint code where the tracepoint will be ignored if the CPU is offline. Use of raw_smp_processor_id() is fine, as there should never be a case where the tracepoint code goes from running on a CPU that is online and suddenly gets migrated to a CPU that is offline. Link: http://lkml.kernel.org/r/1455387773-4245-1-git-send-email-kda@linux-powerpc.org Reported-by: Denis Kirjanov <kda@linux-powerpc.org> Fixes: 97e1c18e8d17b ("tracing: Kernel Tracepoints") Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01ALSA: seq: Fix leak of pool buffer at concurrent writesTakashi Iwai
commit d99a36f4728fcbcc501b78447f625bdcce15b842 upstream. When multiple concurrent writes happen on the ALSA sequencer device right after the open, it may try to allocate vmalloc buffer for each write and leak some of them. It's because the presence check and the assignment of the buffer is done outside the spinlock for the pool. The fix is to move the check and the assignment into the spinlock. (The current implementation is suboptimal, as there can be multiple unnecessary vmallocs because the allocation is done before the check in the spinlock. But the pool size is already checked beforehand, so this isn't a big problem; that is, the only possible path is the multiple writes before any pool assignment, and practically seen, the current coverage should be "good enough".) The issue was triggered by syzkaller fuzzer. BugLink: http://lkml.kernel.org/r/CACT4Y+bSzazpXNvtAr=WXaL8hptqjHwqEyFA+VN2AWEx=aurkg@mail.gmail.com Reported-by: Dmitry Vyukov <dvyukov@google.com> Tested-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01xen/pcifront: Fix mysterious crashes when NUMA locality information was ↵Konrad Rzeszutek Wilk
extracted. commit 4d8c8bd6f2062c9988817183a91fe2e623c8aa5e upstream. Occasionaly PV guests would crash with: pciback 0000:00:00.1: Xen PCI mapped GSI0 to IRQ16 BUG: unable to handle kernel paging request at 0000000d1a8c0be0 .. snip.. <ffffffff8139ce1b>] find_next_bit+0xb/0x10 [<ffffffff81387f22>] cpumask_next_and+0x22/0x40 [<ffffffff813c1ef8>] pci_device_probe+0xb8/0x120 [<ffffffff81529097>] ? driver_sysfs_add+0x77/0xa0 [<ffffffff815293e4>] driver_probe_device+0x1a4/0x2d0 [<ffffffff813c1ddd>] ? pci_match_device+0xdd/0x110 [<ffffffff81529657>] __device_attach_driver+0xa7/0xb0 [<ffffffff815295b0>] ? __driver_attach+0xa0/0xa0 [<ffffffff81527622>] bus_for_each_drv+0x62/0x90 [<ffffffff8152978d>] __device_attach+0xbd/0x110 [<ffffffff815297fb>] device_attach+0xb/0x10 [<ffffffff813b75ac>] pci_bus_add_device+0x3c/0x70 [<ffffffff813b7618>] pci_bus_add_devices+0x38/0x80 [<ffffffff813dc34e>] pcifront_scan_root+0x13e/0x1a0 [<ffffffff817a0692>] pcifront_backend_changed+0x262/0x60b [<ffffffff814644c6>] ? xenbus_gather+0xd6/0x160 [<ffffffff8120900f>] ? put_object+0x2f/0x50 [<ffffffff81465c1d>] xenbus_otherend_changed+0x9d/0xa0 [<ffffffff814678ee>] backend_changed+0xe/0x10 [<ffffffff81463a28>] xenwatch_thread+0xc8/0x190 [<ffffffff810f22f0>] ? woken_wake_function+0x10/0x10 which was the result of two things: When we call pci_scan_root_bus we would pass in 'sd' (sysdata) pointer which was an 'pcifront_sd' structure. However in the pci_device_add it expects that the 'sd' is 'struct sysdata' and sets the dev->node to what is in sd->node (offset 4): set_dev_node(&dev->dev, pcibus_to_node(bus)); __pcibus_to_node(const struct pci_bus *bus) { const struct pci_sysdata *sd = bus->sysdata; return sd->node; } However our structure was pcifront_sd which had nothing at that offset: struct pcifront_sd { int domain; /* 0 4 */ /* XXX 4 bytes hole, try to pack */ struct pcifront_device * pdev; /* 8 8 */ } That is an hole - filled with garbage as we used kmalloc instead of kzalloc (the second problem). This patch fixes the issue by: 1) Use kzalloc to initialize to a well known state. 2) Put 'struct pci_sysdata' at the start of 'pcifront_sd'. That way access to the 'node' will access the right offset. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-04-01xen/pciback: Save the number of MSI-X entries to be copied later.Konrad Rzeszutek Wilk
commit d159457b84395927b5a52adb72f748dd089ad5e5 upstream. Commit 8135cf8b092723dbfcc611fe6fdcb3a36c9951c5 (xen/pciback: Save xen_pci_op commands before processing it) broke enabling MSI-X because it would never copy the resulting vectors into the response. The number of vectors requested was being overwritten by the return value (typically zero for success). Save the number of vectors before processing the op, so the correct number of vectors are copied afterwards. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>