- 07 Sep, 2017 13 commits
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Tejun Heo authored
commit b339752d upstream. When !NUMA, cpumask_of_node(@node) equals cpu_online_mask regardless of @node. The assumption seems that if !NUMA, there shouldn't be more than one node and thus reporting cpu_online_mask regardless of @node is correct. However, that assumption was broken years ago to support DISCONTIGMEM and whether a system has multiple nodes or not is separately controlled by NEED_MULTIPLE_NODES. This means that, on a system with !NUMA && NEED_MULTIPLE_NODES, cpumask_of_node() will report cpu_online_mask for all possible nodes, indicating that the CPUs are associated with multiple nodes which is an impossible configuration. This bug has been around forever but doesn't look like it has caused any noticeable symptoms. However, it triggers a WARN recently added to workqueue to verify NUMA affinity configuration. Fix it by reporting empty cpumask on non-zero nodes if !NUMA. Signed-off-by:
Tejun Heo <tj@kernel.org> Reported-and-tested-by:
Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Yan, Zheng authored
commit dd2bc473 upstream. ceph_readpage() unlocks page prematurely prematurely in the case that page is reading from fscache. Caller of readpage expects that page is uptodate when it get unlocked. So page shoule get locked by completion callback of fscache_read_or_alloc_pages() Signed-off-by:
"Yan, Zheng" <zyan@redhat.com> Reviewed-by:
Jeff Layton <jlayton@redhat.com> Signed-off-by:
Ilya Dryomov <idryomov@gmail.com> Signed-off-by:
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Mel Gorman authored
commit c461ad6a upstream. Wendy Wang reported off-list that a RAS HWPOISON-SOFT test case failed and bisected it to the commit 479f854a ("mm, page_alloc: defer debugging checks of pages allocated from the PCP"). The problem is that a page that was poisoned with madvise() is reused. The commit removed a check that would trigger if DEBUG_VM was enabled but re-enabling the check only fixes the problem as a side-effect by printing a bad_page warning and recovering. The root of the problem is that an madvise() can leave a poisoned page on the per-cpu list. This patch drains all per-cpu lists after pages are poisoned so that they will not be reused. Wendy reports that the test case in question passes with this patch applied. While this could be done in a targeted fashion, it is over-complicated for such a rare operation. Link: http://lkml.kernel.org/r/20170828133414.7qro57jbepdcyz5x@techsingularity.net Fixes: 479f854a ("mm, page_alloc: defer debugging checks of pages allocated from the PCP") Signed-off-by:
Mel Gorman <mgorman@techsingularity.net> Reported-by:
Wang, Wendy <wendy.wang@intel.com> Tested-by:
David Rientjes <rientjes@google.com> Acked-by:
Vlastimil Babka <vbabka@suse.cz> Cc: "Hansen, Dave" <dave.hansen@intel.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
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Eric Biggers authored
commit 355627f5 upstream. Commit 7c051267 ("mm, fork: make dup_mmap wait for mmap_sem for write killable") made it possible to kill a forking task while it is waiting to acquire its ->mmap_sem for write, in dup_mmap(). However, it was overlooked that this introduced an new error path before the new mm_struct's ->uprobes_state.xol_area has been set to NULL after being copied from the old mm_struct by the memcpy in dup_mm(). For a task that has previously hit a uprobe tracepoint, this resulted in the 'struct xol_area' being freed multiple times if the task was killed at just the right time while forking. Fix it by setting ->uprobes_state.xol_area to NULL in mm_init() rather than in uprobe_dup_mmap(). With CONFIG_UPROBE_EVENTS=y, the bug can be reproduced by the same C program given by commit 2b7e8665 ("fork: fix incorrect fput of ->exe_file causing use-after-free"), provided that a uprobe tracepoint has been set on the fork_thread() function. For example: $ gcc reproducer.c -o reproducer -lpthread $ nm reproducer | grep fork_thread 0000000000400719 t fork_thread $ echo "p $PWD/reproducer:0x719" > /sys/kernel/debug/tracing/uprobe_events $ echo 1 > /sys/kernel/debug/tracing/events/uprobes/enable $ ./reproducer Here is the use-after-free reported by KASAN: BUG: KASAN: use-after-free in uprobe_clear_state+0x1c4/0x200 Read of size 8 at addr ffff8800320a8b88 by task reproducer/198 CPU: 1 PID: 198 Comm: reproducer Not tainted 4.13.0-rc7-00015-g36fde05f #255 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-20170228_101828-anatol 04/01/2014 Call Trace: dump_stack+0xdb/0x185 print_address_description+0x7e/0x290 kasan_report+0x23b/0x350 __asan_report_load8_noabort+0x19/0x20 uprobe_clear_state+0x1c4/0x200 mmput+0xd6/0x360 do_exit+0x740/0x1670 do_group_exit+0x13f/0x380 get_signal+0x597/0x17d0 do_signal+0x99/0x1df0 exit_to_usermode_loop+0x166/0x1e0 syscall_return_slowpath+0x258/0x2c0 entry_SYSCALL_64_fastpath+0xbc/0xbe ... Allocated by task 199: save_stack_trace+0x1b/0x20 kasan_kmalloc+0xfc/0x180 kmem_cache_alloc_trace+0xf3/0x330 __create_xol_area+0x10f/0x780 uprobe_notify_resume+0x1674/0x2210 exit_to_usermode_loop+0x150/0x1e0 prepare_exit_to_usermode+0x14b/0x180 retint_user+0x8/0x20 Freed by task 199: save_stack_trace+0x1b/0x20 kasan_slab_free+0xa8/0x1a0 kfree+0xba/0x210 uprobe_clear_state+0x151/0x200 mmput+0xd6/0x360 copy_process.part.8+0x605f/0x65d0 _do_fork+0x1a5/0xbd0 SyS_clone+0x19/0x20 do_syscall_64+0x22f/0x660 return_from_SYSCALL_64+0x0/0x7a Note: without KASAN, you may instead see a "Bad page state" message, or simply a general protection fault. Link: http://lkml.kernel.org/r/20170830033303.17927-1-ebiggers3@gmail.com Fixes: 7c051267 ("mm, fork: make dup_mmap wait for mmap_sem for write killable") Signed-off-by:
Eric Biggers <ebiggers@google.com> Reported-by:
Oleg Nesterov <oleg@redhat.com> Acked-by:
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Stephan Mueller authored
commit 445a5827 upstream. For asynchronous operation, SGs are allocated without a page mapped to them or with a page that is not used (ref-counted). If the SGL is freed, the code must only call put_page for an SG if there was a page assigned and ref-counted in the first place. This fixes a kernel crash when using io_submit with more than one iocb using the sendmsg and sendpage (vmsplice/splice) interface. Signed-off-by:
Stephan Mueller <smueller@chronox.de> Signed-off-by:
Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by:
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Stephen Douthit authored
commit ba201c4f upstream. Compare the number of bytes actually seen on the wire to the byte count field returned by the slave device. Previously we just overwrote the byte count returned by the slave with the real byte count and let the caller figure out if the message was sane. Signed-off-by:
Stephen Douthit <stephend@adiengineering.com> Tested-by:
Dan Priamo <danp@adiengineering.com> Acked-by:
Neil Horman <nhorman@tuxdriver.com> Signed-off-by:
Wolfram Sang <wsa@the-dreams.de> Signed-off-by:
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Stephen Douthit authored
commit b6c159a9 upstream. According to Table 15-14 of the C2000 EDS (Intel doc #510524) the rx data pointed to by the descriptor dptr contains the byte count. desc->rxbytes reports all bytes read on the wire, including the "byte count" byte. So if a device sends 4 bytes in response to a block read, on the wire and in the DMA buffer we see: count data1 data2 data3 data4 0x04 0xde 0xad 0xbe 0xef That's what we want to return in data->block to the next level. Instead we were actually prefixing that with desc->rxbytes: bad count count data1 data2 data3 data4 0x05 0x04 0xde 0xad 0xbe 0xef This was discovered while developing a BMC solution relying on the ipmi_ssif.c driver which was trying to interpret the bogus length field as part of the IPMI response. Signed-off-by:
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Ard Biesheuvel authored
commit 4de43726 upstream. Commit 9ae433bc ("crypto: chacha20 - convert generic and x86 versions to skcipher") ported the existing chacha20 code to use the new skcipher API, and introduced a bug along the way. Unfortunately, the tcrypt tests did not catch the error, and it was only found recently by Tobias. Stefan kindly diagnosed the error, and proposed a fix which is similar to the one below, with the exception that 'walk.stride' is used rather than the hardcoded block size. This does not actually matter in this case, but it's a better example of how to use the skcipher walk API. Fixes: 9ae433bc ("crypto: chacha20 - convert generic and x86 ...") Cc: Steffen Klassert <steffen.klassert@secunet.com> Reported-by:
Tobias Brunner <tobias@strongswan.org> Signed-off-by:
Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by:
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Cameron Gutman authored
commit f5308d1b upstream. The PowerA gamepad initialization quirk worked with the PowerA wired gamepad I had around (0x24c6:0x543a), but a user reported [0] that it didn't work for him, even though our gamepads shared the same vendor and product IDs. When I initially implemented the PowerA quirk, I wanted to avoid actually triggering the rumble action during init. My tests showed that my gamepad would work correctly even if it received a rumble of 0 intensity, so that's what I went with. Unfortunately, this apparently isn't true for all models (perhaps a firmware difference?). This non-working gamepad seems to require the real magic rumble packet that the Microsoft driver sends, which actually vibrates the gamepad. To counteract this effect, I still send the old zero-rumble PowerA quirk packet which cancels the rumble effect before the motors can spin up enough to vibrate. [0]: https://github.com/paroj/xpad/issues/48#issuecomment-313904867Reported-by:
Kyle Beauchamp <kyleabeauchamp@gmail.com> Tested-by:
Cameron Gutman <aicommander@gmail.com> Signed-off-by:
Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by:
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Anthony Martin authored
commit 3f9db52d upstream. User-modified input settings no longer survive a suspend/resume cycle. Starting with 4.12, the touchpad is reinitialized on every reconnect because the hardware appears to be different. This can be reproduced by running the following as root: echo -n reconnect >/sys/devices/platform/i8042/serio1/drvctl A line like the following will show up in dmesg: [30378.295794] psmouse serio1: synaptics: hardware appears to be different: id(149271-149271), model(114865-114865), caps(d047b3-d047b1), ext(b40000-b40000). Note the single bit difference in caps: bit 1 (SYN_CAP_MULTIFINGER). This happens because we modify our stored copy of the device info capabilities when we enable advanced gesture mode but this change is not reflected in the actual hardware capabilities. It worked in the past because synaptics_query_hardware used to modify the stored synaptics_device_info struct instead of filling in a new one, as it does now. Fix it by no longer faking the SYN_CAP_MULTIFINGER bit when setting advanced gesture mode. This necessitated a small refactoring. Fixes: 6c53694f ("Input: synaptics - split device info into a separate structure") Signed-off-by:
Anthony Martin <ality@pbrane.org> Signed-off-by:
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James Hogan authored
commit 2c0e8382 upstream. A SYNC is required between enabling the GIC region and actually trying to use it, even if the first access is a read, otherwise its possible depending on the timing (and in my case depending on the precise alignment of certain kernel code) to hit CM bus errors on that first access. Add the SYNC straight after setting the GIC base. [paul.burton@imgtec.com: Changes later in this series increase our likelihood of hitting this by reducing the amount of code that runs between enabling the GIC & accessing it.] Fixes: a7057270 ("irqchip: mips-gic: Add device-tree support") Signed-off-by:
James Hogan <james.hogan@imgtec.com> Signed-off-by:
Paul Burton <paul.burton@imgtec.com> Acked-by:
Marc Zyngier <marc.zyngier@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jason Cooper <jason@lakedaemon.net> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17019/Signed-off-by:
Ralf Baechle <ralf@linux-mips.org> Signed-off-by:
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Arnd Bergmann authored
commit 7206f9bf upstream. The x86 version of insb/insw/insl uses an inline assembly that does not have the target buffer listed as an output. This can confuse the compiler, leading it to think that a subsequent access of the buffer is uninitialized: drivers/net/wireless/wl3501_cs.c: In function ‘wl3501_mgmt_scan_confirm’: drivers/net/wireless/wl3501_cs.c:665:9: error: ‘sig.status’ is used uninitialized in this function [-Werror=uninitialized] drivers/net/wireless/wl3501_cs.c:668:12: error: ‘sig.cap_info’ may be used uninitialized in this function [-Werror=maybe-uninitialized] drivers/net/sb1000.c: In function 'sb1000_rx': drivers/net/sb1000.c:775:9: error: 'st[0]' is used uninitialized in this function [-Werror=uninitialized] drivers/net/sb1000.c:776:10: error: 'st[1]' may be used uninitialized in this function [-Werror=maybe-uninitialized] drivers/net/sb1000.c:784:11: error: 'st[1]' may be used uninitialized in this function [-Werror=maybe-uninitialized] I tried to mark the exact input buffer as an output here, but couldn't figure it out. As suggested by Linus, marking all memory as clobbered however is good enough too. For the outs operations, I also add the memory clobber, to force the input to be written to local variables. This is probably already guaranteed by the "asm volatile", but it can't hurt to do this for symmetry. Suggested-by:
Arnd Bergmann <arnd@arndb.de> Acked-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
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Mark Rutland authored
commit 289d07a2 upstream. When there's a fatal signal pending, arm64's do_page_fault() implementation returns 0. The intent is that we'll return to the faulting userspace instruction, delivering the signal on the way. However, if we take a fatal signal during fixing up a uaccess, this results in a return to the faulting kernel instruction, which will be instantly retried, resulting in the same fault being taken forever. As the task never reaches userspace, the signal is not delivered, and the task is left unkillable. While the task is stuck in this state, it can inhibit the forward progress of the system. To avoid this, we must ensure that when a fatal signal is pending, we apply any necessary fixup for a faulting kernel instruction. Thus we will return to an error path, and it is up to that code to make forward progress towards delivering the fatal signal. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Laura Abbott <labbott@redhat.com> Reviewed-by:
Steve Capper <steve.capper@arm.com> Tested-by:
James Morse <james.morse@arm.com> Tested-by:
Mark Rutland <mark.rutland@arm.com> Signed-off-by:
Will Deacon <will.deacon@arm.com> Signed-off-by:
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- 30 Aug, 2017 27 commits
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Greg Kroah-Hartman authored
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Benjamin Herrenschmidt authored
commit 1a92a80a upstream. There is no guarantee that the various isync's involved with the context switch will order the update of the CPU mask with the first TLB entry for the new context being loaded by the HW. Be safe here and add a memory barrier to order any subsequent load/store which may bring entries into the TLB. The corresponding barrier on the other side already exists as pte updates use pte_xchg() which uses __cmpxchg_u64 which has a sync after the atomic operation. Cc: stable@vger.kernel.org Signed-off-by:
Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by:
Nicholas Piggin <npiggin@gmail.com> [mpe: Add comments in the code] [mpe: Backport to 4.12, minor context change] Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au> Signed-off-by:
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Lv Zheng authored
commit 98529b92 upstream. Commit 2a570840 (ACPI / EC: Fix a gap that ECDT EC cannot handle EC events) introduced acpi_ec_ecdt_start(), but that function is invoked before acpi_ec_query_init(), which is too early. This causes the kernel to crash if an EC event occurs after boot, when ec_query_wq is not valid: BUG: unable to handle kernel NULL pointer dereference at 0000000000000102 ... Workqueue: events acpi_ec_event_handler task: ffff9f539790dac0 task.stack: ffffb437c0e10000 RIP: 0010:__queue_work+0x32/0x430 Normally, the DSDT EC should always be valid, so acpi_ec_ecdt_start() is actually a no-op in the majority of cases. However, commit c712bb58 (ACPI / EC: Add support to skip boot stage DSDT probe) caused the probing of the DSDT EC as the "boot EC" to be skipped when the ECDT EC is valid and uncovered the bug. Fix this issue by invoking acpi_ec_ecdt_start() after acpi_ec_query_init() in acpi_ec_init(). Link: https://jira01.devtools.intel.com/browse/LCK-4348 Fixes: 2a570840 (ACPI / EC: Fix a gap that ECDT EC cannot handle EC events) Fixes: c712bb58 (ACPI / EC: Add support to skip boot stage DSDT probe) Reported-by:
Feng Chenzhou <chenzhoux.feng@intel.com> Signed-off-by:
Lv Zheng <lv.zheng@intel.com> [ rjw: Changelog ] Signed-off-by:
Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by:
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Hanjun Guo authored
commit f7f3dd5b upstream. ACPI HID for Hisilicon Hip07/08 should be HISI02A1/2, not HISI0A21/2, HISI02A1/2 was tested ok but was modified by the stupid typo when upstream the patches (by me), correct them to the right IDs (matching the IDs in drivers/i2c/busses/i2c-designware-platdrv.c). Fixes: 6e14cf36 (ACPI / APD: Add clock frequency for Hisilicon Hip07/08 I2C controller) Reported-by:
Tao Tian <tiantao6@huawei.com> Signed-off-by:
Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by:
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Dave Jiang authored
commit f3fd2afe upstream. It seems that under certain scenarios the SPAD can have bogus values caused by an agent (i.e. BIOS or other software) that is not the kernel driver, and that causes memory window setup failure. This should not cause the link to be disabled because if we do that, the driver will never recover again. We have verified in testing that this issue happens and prevents proper link recovery. Signed-off-by:
Dave Jiang <dave.jiang@intel.com> Acked-by:
Allen Hubbe <Allen.Hubbe@dell.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us> Fixes: 84f76685 ("ntb: stop link work when we do not have memory") Signed-off-by:
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Logan Gunthorpe authored
commit 0eb46345 upstream. After the link tests, there is a race on one side of the test for the link coming up. It's possible, in some cases, for the test script to write to the 'peer_trans' files before the link has come up. To fix this, we simply use the link event file to ensure both sides see the link as up before continuning. Signed-off-by:
Logan Gunthorpe <logang@deltatee.com> Acked-by:
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Linus Torvalds authored
commit 0cc3b0ec upstream. We have a MAX_LFS_FILESIZE macro that is meant to be filled in by filesystems (and other IO targets) that know they are 64-bit clean and don't have any 32-bit limits in their IO path. It turns out that our 32-bit value for that limit was bogus. On 32-bit, the VM layer is limited by the page cache to only 32-bit index values, but our logic for that was confusing and actually wrong. We used to define that value to (((loff_t)PAGE_SIZE << (BITS_PER_LONG-1))-1) which is actually odd in several ways: it limits the index to 31 bits, and then it limits files so that they can't have data in that last byte of a page that has the highest 31-bit index (ie page index 0x7fffffff). Neither of those limitations make sense. The index is actually the full 32 bit unsigned value, and we can use that whole full page. So the maximum size of the file would logically be "PAGE_SIZE << BITS_PER_LONG". However, we do wan tto avoid the maximum index, because we have code that iterates over the page indexes, and we don't want that code to overflow. So the maximum size of a file on a 32-bit host should actually be one page less than the full 32-bit index. So the actual limit is ULONG_MAX << PAGE_SHIFT. That means that we will not actually be using the page of that last index (ULONG_MAX), but we can grow a file up to that limit. The wrong value of MAX_LFS_FILESIZE actually caused problems for Doug Nazar, who was still using a 32-bit host, but with a 9.7TB 2 x RAID5 volume. It turns out that our old MAX_LFS_FILESIZE was 8TiB (well, one byte less), but the actual true VM limit is one page less than 16TiB. This was invisible until commit c2a9737f ("vfs,mm: fix a dead loop in truncate_inode_pages_range()"), which started applying that MAX_LFS_FILESIZE limit to block devices too. NOTE! On 64-bit, the page index isn't a limiter at all, and the limit is actually just the offset type itself (loff_t), which is signed. But for clarity, on 64-bit, just use the maximum signed value, and don't make people have to count the number of 'f' characters in the hex constant. So just use LLONG_MAX for the 64-bit case. That was what the value had been before too, just written out as a hex constant. Fixes: c2a9737f ("vfs,mm: fix a dead loop in truncate_inode_pages_range()") Reported-and-tested-by:
Doug Nazar <nazard@nazar.ca> Cc: Andreas Dilger <adilger@dilger.ca> Cc: Mark Fasheh <mfasheh@versity.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Dave Kleikamp <shaggy@kernel.org> Signed-off-by:
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Joerg Roedel authored
commit 2926a2aa upstream. The struct iommu_device has a 'struct device' embedded into it, not as a pointer, but the whole struct. In the conversion of the iommu drivers to use struct iommu_device it was forgotten that the relase function for that struct device simply calls kfree() on the pointer. This frees memory that was never allocated and causes memory corruption. To fix this issue, use a pointer to struct device instead of embedding the whole struct. This needs some updates in the iommu sysfs code as well as the Intel VT-d and AMD IOMMU driver. Reported-by:
Sebastian Ott <sebott@linux.vnet.ibm.com> Fixes: 39ab9555 ('iommu: Add sysfs bindings for struct iommu_device') Signed-off-by:
Joerg Roedel <jroedel@suse.de> Signed-off-by:
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Charles Milette authored
commit f299aec6 upstream. Add support for USB Device Rosewill RNX-N150NUB. VendorID: 0x0bda, ProductID: 0xffef Signed-off-by:
Charles Milette <charles.milette@gmail.com> Signed-off-by:
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Lorenzo Bianconi authored
commit 8b35a5f8 upstream. Remove IRQ active low support for LSM303AGR since the sensor does not support that capability for data-ready line Fixes: a9fd053b (iio: st_sensors: support active-low interrupts) Signed-off-by:
Lorenzo Bianconi <lorenzo.bianconi@st.com> Reviewed-by:
Linus Walleij <linus.walleij@linaro.org> Signed-off-by:
Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by:
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Lorenzo Bianconi authored
commit 541ee9b2 upstream. Fixes: 97865fe4 (iio: st_sensors: verify interrupt event to status) Signed-off-by:
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Srinivas Pandruvada authored
commit f1664eaa upstream. It has been reported for a while that with iio-sensor-proxy service the rotation only works after one suspend/resume cycle. This required a wait in the systemd unit file to avoid race. I found a Yoga 900 where I could reproduce this. The problem scenerio is: - During sensor driver init, enable run time PM and also set a auto-suspend for 3 seconds. This result in one runtime resume. But there is a check to avoid a powerup in this sequence, but rpm is active - User space iio-sensor-proxy tries to power up the sensor. Since rpm is active it will simply return. But sensors were not actually powered up in the prior sequence, so actaully the sensors will not work - After 3 seconds the auto suspend kicks If we add a wait in systemd service file to fire iio-sensor-proxy after 3 seconds, then now everything will work as the runtime resume will actually powerup the sensor as this is a user request. To avoid this: - Remove the check to match user requested state, this will cause a brief powerup, but if the iio-sensor-proxy starts immediately it will still work as the sensors are ON. - Also move the autosuspend delay to place when user requested turn off of sensors, like after user finished raw read or buffer disable Signed-off-by:
Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Tested-by:
Bastien Nocera <hadess@hadess.net> Signed-off-by:
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Dragos Bogdan authored
commit fdd0d32e upstream. According to the datasheet, the range of the acceleration is [-10 g, + 10 g], so the scale factor should be 10 instead of 5. Signed-off-by:
Dragos Bogdan <dragos.bogdan@analog.com> Acked-by:
Lars-Peter Clausen <lars@metafoo.de> Signed-off-by:
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Martijn Coenen authored
commit b2a6d1b9 upstream. Commit c4ea41ba ("binder: use group leader instead of open thread")' was incomplete and didn't update a check in binder_mmap(), causing all mmap() calls into the binder driver to fail. Signed-off-by:
Martijn Coenen <maco@android.com> Tested-by:
John Stultz <john.stultz@linaro.org> Signed-off-by:
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Riley Andrews authored
commit 00b40d61 upstream. Use wake_up_interruptible_sync() to hint to the scheduler binder transactions are synchronous wakeups. Disable preemption while waking to avoid ping-ponging on the binder lock. Signed-off-by:
Todd Kjos <tkjos@google.com> Signed-off-by:
Omprakash Dhyade <odhyade@codeaurora.org> Signed-off-by:
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Todd Kjos authored
commit c4ea41ba upstream. The binder allocator assumes that the thread that called binder_open will never die for the lifetime of that proc. That thread is normally the group_leader, however it may not be. Use the group_leader instead of current. Signed-off-by:
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Todd Kjos authored
commit a2b18708 upstream. This reverts commit a906d693. The patch introduced a race in the binder driver. An attempt to fix the race was submitted in "[PATCH v2] android: binder: fix dangling pointer comparison", however the conclusion in the discussion for that patch was that the original patch should be reverted. The reversion is being done as part of the fine-grained locking patchset since the patch would need to be refactored when proc->vmm_vm_mm is removed from struct binder_proc and added in the binder allocator. Signed-off-by:
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Jeffy Chen authored
commit 25717382 upstream. It looks like bnep_session has same pattern as the issue reported in old rfcomm: while (1) { set_current_state(TASK_INTERRUPTIBLE); if (condition) break; // may call might_sleep here schedule(); } __set_current_state(TASK_RUNNING); Which fixed at: dfb2fae7 Bluetooth: Fix nested sleeps So let's fix it at the same way, also follow the suggestion of: https://lwn.net/Articles/628628/Signed-off-by:
Jeffy Chen <jeffy.chen@rock-chips.com> Reviewed-by:
Brian Norris <briannorris@chromium.org> Reviewed-by:
AL Yu-Chen Cho <acho@suse.com> Signed-off-by:
Marcel Holtmann <marcel@holtmann.org> Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by:
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Jeffy Chen authored
commit f06d9773 upstream. It looks like cmtp_session has same pattern as the issue reported in old rfcomm: while (1) { set_current_state(TASK_INTERRUPTIBLE); if (condition) break; // may call might_sleep here schedule(); } __set_current_state(TASK_RUNNING); Which fixed at: dfb2fae7 Bluetooth: Fix nested sleeps So let's fix it at the same way, also follow the suggestion of: https://lwn.net/Articles/628628/Signed-off-by:
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Jeffy Chen authored
commit 5da8e47d upstream. It looks like hidp_session_thread has same pattern as the issue reported in old rfcomm: while (1) { set_current_state(TASK_INTERRUPTIBLE); if (condition) break; // may call might_sleep here schedule(); } __set_current_state(TASK_RUNNING); Which fixed at: dfb2fae7 Bluetooth: Fix nested sleeps So let's fix it at the same way, also follow the suggestion of: https://lwn.net/Articles/628628/Signed-off-by:
Rohit Vaswani <rvaswani@nvidia.com> Signed-off-by:
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Mateusz Jurczyk authored
commit f55ce7b0 upstream. Verify that the length of the socket buffer is sufficient to cover the nlmsghdr structure before accessing the nlh->nlmsg_len field for further input sanitization. If the client only supplies 1-3 bytes of data in sk_buff, then nlh->nlmsg_len remains partially uninitialized and contains leftover memory from the corresponding kernel allocation. Operating on such data may result in indeterminate evaluation of the nlmsg_len < NLMSG_HDRLEN expression. The bug was discovered by a runtime instrumentation designed to detect use of uninitialized memory in the kernel. The patch prevents this and other similar tools (e.g. KMSAN) from flagging this behavior in the future. Signed-off-by:
Mateusz Jurczyk <mjurczyk@google.com> Signed-off-by:
Pablo Neira Ayuso <pablo@netfilter.org> Cc: Florian Westphal <fw@strlen.de> Signed-off-by:
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Florian Westphal authored
commit 97772bcd upstream. When doing initial conversion to rhashtable I replaced the bucket walk with a single rhashtable_lookup_fast(). When moving to rhlist I failed to properly walk the list of identical tuples, but that is what is needed for this to work correctly. The table contains the original tuples, so the reply tuples are all distinct. We currently decide that mapping is (not) in range only based on the first entry, but in case its not we need to try the reply tuple of the next entry until we either find an in-range mapping or we checked all the entries. This bug makes nat core attempt collision resolution while it might be able to use the mapping as-is. Fixes: 870190a9 ("netfilter: nat: convert nat bysrc hash to rhashtable") Reported-by:
Jaco Kroon <jaco@uls.co.za> Tested-by:
Florian Westphal <fw@strlen.de> Signed-off-by:
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Florian Westphal authored
commit 36ac344e upstream. We crash in __nf_ct_expect_check, it calls nf_ct_remove_expect on the uninitialised expectation instead of existing one, so del_timer chokes on random memory address. Fixes: ec0e3f01 ("netfilter: nf_ct_expect: Add nf_ct_remove_expect()") Reported-by:
Sergey Kvachonok <ravenexp@gmail.com> Tested-by:
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Vadim Lomovtsev authored
commit eebe53e8 upstream. While running nfs/connectathon tests kernel NULL-pointer exception has been observed due to races in svcsock.c. Race is appear when kernel accepts connection by kernel_accept (which creates new socket) and start queuing ingress packets to new socket. This happens in ksoftirq context which could run concurrently on a different core while new socket setup is not done yet. The fix is to re-order socket user data init sequence and add write/read barrier calls to be sure that we got proper values for callback pointers before actually calling them. Test results: nfs/connectathon reports '0' failed tests for about 200+ iterations. Crash log: ---<-snip->--- [ 6708.638984] Unable to handle kernel NULL pointer dereference at virtual address 00000000 [ 6708.647093] pgd = ffff0000094e0000 [ 6708.650497] [00000000] *pgd=0000010ffff90003, *pud=0000010ffff90003, *pmd=0000010ffff80003, *pte=0000000000000000 [ 6708.660761] Internal error: Oops: 86000005 [#1] SMP [ 6708.665630] Modules linked in: nfsv3 nfnetlink_queue nfnetlink_log nfnetlink rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache overlay xt_CONNSECMARK xt_SECMARK xt_conntrack iptable_security ip_tables ah4 xfrm4_mode_transport sctp tun binfmt_misc ext4 jbd2 mbcache loop tcp_diag udp_diag inet_diag rpcrdma ib_isert iscsi_target_mod ib_iser rdma_cm iw_cm libiscsi scsi_transport_iscsi ib_srpt target_core_mod ib_srp scsi_transport_srp ib_ipoib ib_ucm ib_uverbs ib_umad ib_cm ib_core nls_koi8_u nls_cp932 ts_kmp nf_conntrack_ipv4 nf_defrag_ipv4 nf_conntrack vfat fat ghash_ce sha2_ce sha1_ce cavium_rng_vf i2c_thunderx sg thunderx_edac i2c_smbus edac_core cavium_rng nfsd auth_rpcgss nfs_acl lockd grace sunrpc xfs libcrc32c nicvf nicpf ast i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops [ 6708.736446] ttm drm i2c_core thunder_bgx thunder_xcv mdio_thunder mdio_cavium dm_mirror dm_region_hash dm_log dm_mod [last unloaded: stap_3c300909c5b3f46dcacd49aab3334af_87021] [ 6708.752275] CPU: 84 PID: 0 Comm: swapper/84 Tainted: G W OE 4.11.0-4.el7.aarch64 #1 [ 6708.760787] Hardware name: www.cavium.com CRB-2S/CRB-2S, BIOS 0.3 Mar 13 2017 [ 6708.767910] task: ffff810006842e80 task.stack: ffff81000689c000 [ 6708.773822] PC is at 0x0 [ 6708.776739] LR is at svc_data_ready+0x38/0x88 [sunrpc] [ 6708.781866] pc : [<0000000000000000>] lr : [<ffff0000029d7378>] pstate: 60000145 [ 6708.789248] sp : ffff810ffbad3900 [ 6708.792551] x29: ffff810ffbad3900 x28: ffff000008c73d58 [ 6708.797853] x27: 0000000000000000 x26: ffff81000bbe1e00 [ 6708.803156] x25: 0000000000000020 x24: ffff800f7410bf28 [ 6708.808458] x23: ffff000008c63000 x22: ffff000008c63000 [ 6708.813760] x21: ffff800f7410bf28 x20: ffff81000bbe1e00 [ 6708.819063] x19: ffff810012412400 x18: 00000000d82a9df2 [ 6708.824365] x17: 0000000000000000 x16: 0000000000000000 [ 6708.829667] x15: 0000000000000000 x14: 0000000000000001 [ 6708.834969] x13: 0000000000000000 x12: 722e736f622e676e [ 6708.840271] x11: 00000000f814dd99 x10: 0000000000000000 [ 6708.845573] x9 : 7374687225000000 x8 : 0000000000000000 [ 6708.850875] x7 : 0000000000000000 x6 : 0000000000000000 [ 6708.856177] x5 : 0000000000000028 x4 : 0000000000000000 [ 6708.861479] x3 : 0000000000000000 x2 : 00000000e5000000 [ 6708.866781] x1 : 0000000000000000 x0 : ffff81000bbe1e00 [ 6708.872084] [ 6708.873565] Process swapper/84 (pid: 0, stack limit = 0xffff81000689c000) [ 6708.880341] Stack: (0xffff810ffbad3900 to 0xffff8100068a0000) [ 6708.886075] Call trace: [ 6708.888513] Exception stack(0xffff810ffbad3710 to 0xffff810ffbad3840) [ 6708.894942] 3700: ffff810012412400 0001000000000000 [ 6708.902759] 3720: ffff810ffbad3900 0000000000000000 0000000060000145 ffff800f79300000 [ 6708.910577] 3740: ffff000009274d00 00000000000003ea 0000000000000015 ffff000008c63000 [ 6708.918395] 3760: ffff810ffbad3830 ffff800f79300000 000000000000004d 0000000000000000 [ 6708.926212] 3780: ffff810ffbad3890 ffff0000080f88dc ffff800f79300000 000000000000004d [ 6708.934030] 37a0: ffff800f7930093c ffff000008c63000 0000000000000000 0000000000000140 [ 6708.941848] 37c0: ffff000008c2c000 0000000000040b00 ffff81000bbe1e00 0000000000000000 [ 6708.949665] 37e0: 00000000e5000000 0000000000000000 0000000000000000 0000000000000028 [ 6708.957483] 3800: 0000000000000000 0000000000000000 0000000000000000 7374687225000000 [ 6708.965300] 3820: 0000000000000000 00000000f814dd99 722e736f622e676e 0000000000000000 [ 6708.973117] [< (null)>] (null) [ 6708.977824] [<ffff0000086f9fa4>] tcp_data_queue+0x754/0xc5c [ 6708.983386] [<ffff0000086fa64c>] tcp_rcv_established+0x1a0/0x67c [ 6708.989384] [<ffff000008704120>] tcp_v4_do_rcv+0x15c/0x22c [ 6708.994858] [<ffff000008707418>] tcp_v4_rcv+0xaf0/0xb58 [ 6709.000077] [<ffff0000086df784>] ip_local_deliver_finish+0x10c/0x254 [ 6709.006419] [<ffff0000086dfea4>] ip_local_deliver+0xf0/0xfc [ 6709.011980] [<ffff0000086dfad4>] ip_rcv_finish+0x208/0x3a4 [ 6709.017454] [<ffff0000086e018c>] ip_rcv+0x2dc/0x3c8 [ 6709.022328] [<ffff000008692fc8>] __netif_receive_skb_core+0x2f8/0xa0c [ 6709.028758] [<ffff000008696068>] __netif_receive_skb+0x38/0x84 [ 6709.034580] [<ffff00000869611c>] netif_receive_skb_internal+0x68/0xdc [ 6709.041010] [<ffff000008696bc0>] napi_gro_receive+0xcc/0x1a8 [ 6709.046690] [<ffff0000014b0fc4>] nicvf_cq_intr_handler+0x59c/0x730 [nicvf] [ 6709.053559] [<ffff0000014b1380>] nicvf_poll+0x38/0xb8 [nicvf] [ 6709.059295] [<ffff000008697a6c>] net_rx_action+0x2f8/0x464 [ 6709.064771] [<ffff000008081824>] __do_softirq+0x11c/0x308 [ 6709.070164] [<ffff0000080d14e4>] irq_exit+0x12c/0x174 [ 6709.075206] [<ffff00000813101c>] __handle_domain_irq+0x78/0xc4 [ 6709.081027] [<ffff000008081608>] gic_handle_irq+0x94/0x190 [ 6709.086501] Exception stack(0xffff81000689fdf0 to 0xffff81000689ff20) [ 6709.092929] fde0: 0000810ff2ec0000 ffff000008c10000 [ 6709.100747] fe00: ffff000008c70ef4 0000000000000001 0000000000000000 ffff810ffbad9b18 [ 6709.108565] fe20: ffff810ffbad9c70 ffff8100169d3800 ffff810006843ab0 ffff81000689fe80 [ 6709.116382] fe40: 0000000000000bd0 0000ffffdf979cd0 183f5913da192500 0000ffff8a254ce4 [ 6709.124200] fe60: 0000ffff8a254b78 0000aaab10339808 0000000000000000 0000ffff8a0c2a50 [ 6709.132018] fe80: 0000ffffdf979b10 ffff000008d6d450 ffff000008c10000 ffff000008d6d000 [ 6709.139836] fea0: 0000000000000054 ffff000008cd3dbc 0000000000000000 0000000000000000 [ 6709.147653] fec0: 0000000000000000 0000000000000000 0000000000000000 ffff81000689ff20 [ 6709.155471] fee0: ffff000008085240 ffff81000689ff20 ffff000008085244 0000000060000145 [ 6709.163289] ff00: ffff81000689ff10 ffff00000813f1e4 ffffffffffffffff ffff00000813f238 [ 6709.171107] [<ffff000008082eb4>] el1_irq+0xb4/0x140 [ 6709.175976] [<ffff000008085244>] arch_cpu_idle+0x44/0x11c [ 6709.181368] [<ffff0000087bf3b8>] default_idle_call+0x20/0x30 [ 6709.187020] [<ffff000008116d50>] do_idle+0x158/0x1e4 [ 6709.191973] [<ffff000008116ff4>] cpu_startup_entry+0x2c/0x30 [ 6709.197624] [<ffff00000808e7cc>] secondary_start_kernel+0x13c/0x160 [ 6709.203878] [<0000000001bc71c4>] 0x1bc71c4 [ 6709.207967] Code: bad PC value [ 6709.211061] SMP: stopping secondary CPUs [ 6709.218830] Starting crashdump kernel... [ 6709.222749] Bye! ---<-snip>--- Signed-off-by:
Vadim Lomovtsev <vlomovts@redhat.com> Reviewed-by:
J. Bruce Fields <bfields@redhat.com> Signed-off-by:
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Eric Biggers authored
commit ccd5b323 upstream. The following commit: 39a0526f ("x86/mm: Factor out LDT init from context init") renamed init_new_context() to init_new_context_ldt() and added a new init_new_context() which calls init_new_context_ldt(). However, the error code of init_new_context_ldt() was ignored. Consequently, if a memory allocation in alloc_ldt_struct() failed during a fork(), the ->context.ldt of the new task remained the same as that of the old task (due to the memcpy() in dup_mm()). ldt_struct's are not intended to be shared, so a use-after-free occurred after one task exited. Fix the bug by making init_new_context() pass through the error code of init_new_context_ldt(). This bug was found by syzkaller, which encountered the following splat: BUG: KASAN: use-after-free in free_ldt_struct.part.2+0x10a/0x150 arch/x86/kernel/ldt.c:116 Read of size 4 at addr ffff88006d2cb7c8 by task kworker/u9:0/3710 CPU: 1 PID: 3710 Comm: kworker/u9:0 Not tainted 4.13.0-rc4-next-20170811 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x24e/0x340 mm/kasan/report.c:409 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:429 free_ldt_struct.part.2+0x10a/0x150 arch/x86/kernel/ldt.c:116 free_ldt_struct arch/x86/kernel/ldt.c:173 [inline] destroy_context_ldt+0x60/0x80 arch/x86/kernel/ldt.c:171 destroy_context arch/x86/include/asm/mmu_context.h:157 [inline] __mmdrop+0xe9/0x530 kernel/fork.c:889 mmdrop include/linux/sched/mm.h:42 [inline] exec_mmap fs/exec.c:1061 [inline] flush_old_exec+0x173c/0x1ff0 fs/exec.c:1291 load_elf_binary+0x81f/0x4ba0 fs/binfmt_elf.c:855 search_binary_handler+0x142/0x6b0 fs/exec.c:1652 exec_binprm fs/exec.c:1694 [inline] do_execveat_common.isra.33+0x1746/0x22e0 fs/exec.c:1816 do_execve+0x31/0x40 fs/exec.c:1860 call_usermodehelper_exec_async+0x457/0x8f0 kernel/umh.c:100 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 Allocated by task 3700: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3627 kmalloc include/linux/slab.h:493 [inline] alloc_ldt_struct+0x52/0x140 arch/x86/kernel/ldt.c:67 write_ldt+0x7b7/0xab0 arch/x86/kernel/ldt.c:277 sys_modify_ldt+0x1ef/0x240 arch/x86/kernel/ldt.c:307 entry_SYSCALL_64_fastpath+0x1f/0xbe Freed by task 3700: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3503 [inline] kfree+0xca/0x250 mm/slab.c:3820 free_ldt_struct.part.2+0xdd/0x150 arch/x86/kernel/ldt.c:121 free_ldt_struct arch/x86/kernel/ldt.c:173 [inline] destroy_context_ldt+0x60/0x80 arch/x86/kernel/ldt.c:171 destroy_context arch/x86/include/asm/mmu_context.h:157 [inline] __mmdrop+0xe9/0x530 kernel/fork.c:889 mmdrop include/linux/sched/mm.h:42 [inline] __mmput kernel/fork.c:916 [inline] mmput+0x541/0x6e0 kernel/fork.c:927 copy_process.part.36+0x22e1/0x4af0 kernel/fork.c:1931 copy_process kernel/fork.c:1546 [inline] _do_fork+0x1ef/0xfb0 kernel/fork.c:2025 SYSC_clone kernel/fork.c:2135 [inline] SyS_clone+0x37/0x50 kernel/fork.c:2129 do_syscall_64+0x26c/0x8c0 arch/x86/entry/common.c:287 return_from_SYSCALL_64+0x0/0x7a Here is a C reproducer: #include <asm/ldt.h> #include <pthread.h> #include <signal.h> #include <stdlib.h> #include <sys/syscall.h> #include <sys/wait.h> #include <unistd.h> static void *fork_thread(void *_arg) { fork(); } int main(void) { struct user_desc desc = { .entry_number = 8191 }; syscall(__NR_modify_ldt, 1, &desc, sizeof(desc)); for (;;) { if (fork() == 0) { pthread_t t; srand(getpid()); pthread_create(&t, NULL, fork_thread, NULL); usleep(rand() % 10000); syscall(__NR_exit_group, 0); } wait(NULL); } } Note: the reproducer takes advantage of the fact that alloc_ldt_struct() may use vmalloc() to allocate a large ->entries array, and after commit: 5d17a73a ("vmalloc: back off when the current task is killed") it is possible for userspace to fail a task's vmalloc() by sending a fatal signal, e.g. via exit_group(). It would be more difficult to reproduce this bug on kernels without that commit. This bug only affected kernels with CONFIG_MODIFY_LDT_SYSCALL=y. Signed-off-by:
Dave Hansen <dave.hansen@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Fixes: 39a0526f ("x86/mm: Factor out LDT init from context init") Link: http://lkml.kernel.org/r/20170824175029.76040-1-ebiggers3@gmail.comSigned-off-by:
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Nicholas Piggin authored
commit 2fe59f50 upstream. When a timer base is idle, it is forwarded when a new timer is added to ensure that granularity does not become excessive. When not idle, the timer tick is expected to increment the base. However there are several problems: - If an existing timer is modified, the base is forwarded only after the index is calculated. - The base is not forwarded by add_timer_on. - There is a window after a timer is restarted from a nohz idle, after it is marked not-idle and before the timer tick on this CPU, where a timer may be added but the ancient base does not get forwarded. These result in excessive granularity (a 1 jiffy timeout can blow out to 100s of jiffies), which cause the rcu lockup detector to trigger, among other things. Fix this by keeping track of whether the timer base has been idle since it was last run or forwarded, and if so then forward it before adding a new timer. There is still a case where mod_timer optimises the case of a pending timer mod with the same expiry time, where the timer can see excessive granularity relative to the new, shorter interval. A comment is added, but it's not changed because it is an important fastpath for networking. This has been tested and found to fix the RCU softlockup messages. Testing was also done with tracing to measure requested versus achieved wakeup latencies for all non-deferrable timers in an idle system (with no lockup watchdogs running). Wakeup latency relative to absolute latency is calculated (note this suffers from round-up skew at low absolute times) and analysed: max avg std upstream 506.0 1.20 4.68 patched 2.0 1.08 0.15 The bug was noticed due to the lockup detector Kconfig changes dropping it out of people's .configs and resulting in larger base clk skew When the lockup detectors are enabled, no CPU can go idle for longer than 4 seconds, which limits the granularity errors. Sub-optimal timer behaviour is observable on a smaller scale in that case: max avg std upstream 9.0 1.05 0.19 patched 2.0 1.04 0.11 Fixes: Fixes: a683f390 ("timers: Forward the wheel clock whenever possible") Signed-off-by:
Thomas Gleixner <tglx@linutronix.de> Tested-by:
David Miller <davem@davemloft.net> Cc: dzickus@redhat.com Cc: sfr@canb.auug.org.au Cc: mpe@ellerman.id.au Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: linuxarm@huawei.com Cc: abdhalee@linux.vnet.ibm.com Cc: John Stultz <john.stultz@linaro.org> Cc: akpm@linux-foundation.org Cc: paulmck@linux.vnet.ibm.com Cc: torvalds@linux-foundation.org Link: http://lkml.kernel.org/r/20170822084348.21436-1-npiggin@gmail.comSigned-off-by:
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Mark Rutland authored
commit 64aee2a9 upstream. Regardless of which events form a group, it does not make sense for the events to target different tasks and/or CPUs, as this leaves the group inconsistent and impossible to schedule. The core perf code assumes that these are consistent across (successfully intialised) groups. Core perf code only verifies this when moving SW events into a HW context. Thus, we can violate this requirement for pure SW groups and pure HW groups, unless the relevant PMU driver happens to perform this verification itself. These mismatched groups subsequently wreak havoc elsewhere. For example, we handle watchpoints as SW events, and reserve watchpoint HW on a per-CPU basis at pmu::event_init() time to ensure that any event that is initialised is guaranteed to have a slot at pmu::add() time. However, the core code only checks the group leader's cpu filter (via event_filter_match()), and can thus install follower events onto CPUs violating thier (mismatched) CPU filters, potentially installing them into a CPU without sufficient reserved slots. This can be triggered with the below test case, resulting in warnings from arch backends. #define _GNU_SOURCE #include <linux/hw_breakpoint.h> #include <linux/perf_event.h> #include <sched.h> #include <stdio.h> #include <sys/prctl.h> #include <sys/syscall.h> #include <unistd.h> static int perf_event_open(struct perf_event_attr *attr, pid_t pid, int cpu, int group_fd, unsigned long flags) { return syscall(__NR_perf_event_open, attr, pid, cpu, group_fd, flags); } char watched_char; struct perf_event_attr wp_attr = { .type = PERF_TYPE_BREAKPOINT, .bp_type = HW_BREAKPOINT_RW, .bp_addr = (unsigned long)&watched_char, .bp_len = 1, .size = sizeof(wp_attr), }; int main(int argc, char *argv[]) { int leader, ret; cpu_set_t cpus; /* * Force use of CPU0 to ensure our CPU0-bound events get scheduled. */ CPU_ZERO(&cpus); CPU_SET(0, &cpus); ret = sched_setaffinity(0, sizeof(cpus), &cpus); if (ret) { printf("Unable to set cpu affinity\n"); return 1; } /* open leader event, bound to this task, CPU0 only */ leader = perf_event_open(&wp_attr, 0, 0, -1, 0); if (leader < 0) { printf("Couldn't open leader: %d\n", leader); return 1; } /* * Open a follower event that is bound to the same task, but a * different CPU. This means that the group should never be possible to * schedule. */ ret = perf_event_open(&wp_attr, 0, 1, leader, 0); if (ret < 0) { printf("Couldn't open mismatched follower: %d\n", ret); return 1; } else { printf("Opened leader/follower with mismastched CPUs\n"); } /* * Open as many independent events as we can, all bound to the same * task, CPU0 only. */ do { ret = perf_event_open(&wp_attr, 0, 0, -1, 0); } while (ret >= 0); /* * Force enable/disble all events to trigger the erronoeous * installation of the follower event. */ printf("Opened all events. Toggling..\n"); for (;;) { prctl(PR_TASK_PERF_EVENTS_DISABLE, 0, 0, 0, 0); prctl(PR_TASK_PERF_EVENTS_ENABLE, 0, 0, 0, 0); } return 0; } Fix this by validating this requirement regardless of whether we're moving events. Signed-off-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Zhou Chengming <zhouchengming1@huawei.com> Link: http://lkml.kernel.org/r/1498142498-15758-1-git-send-email-mark.rutland@arm.comSigned-off-by:
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