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2017-08-25tcp: fix refcnt leak with ebpf congestion controlSabrina Dubroca
There are a few bugs around refcnt handling in the new BPF congestion control setsockopt: - The new ca is assigned to icsk->icsk_ca_ops even in the case where we cannot get a reference on it. This would lead to a use after free, since that ca is going away soon. - Changing the congestion control case doesn't release the refcnt on the previous ca. - In the reinit case, we first leak a reference on the old ca, then we call tcp_reinit_congestion_control on the ca that we have just assigned, leading to deinitializing the wrong ca (->release of the new ca on the old ca's data) and releasing the refcount on the ca that we actually want to use. This is visible by building (for example) BIC as a module and setting net.ipv4.tcp_congestion_control=bic, and using tcp_cong_kern.c from samples/bpf. This patch fixes the refcount issues, and moves reinit back into tcp core to avoid passing a ca pointer back to BPF. Fixes: 91b5b21c7c16 ("bpf: Add support for changing congestion control") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Acked-by: Lawrence Brakmo <brakmo@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-25hinic: skb_pad() frees on errorDan Carpenter
The skb_pad() function frees the skb on error, so this code has a double free. Fixes: 00e57a6d4ad3 ("net-next/hinic: Add Tx operation") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-25Merge branch 'ipv6-sr-updates'David S. Miller
David Lebrun says: ==================== net: updates for IPv6 Segment Routing v2: seg6_lwt_headroom() is not relevant for lwtunnel_input_redirect() use cases, and L2ENCAP only uses this redirection. Fix incoherence between arbitrary MAC header size support and fixed headroom computation by setting only LWTUNNEL_STATE_INPUT_REDIRECT for L2ENCAP mode. This patch series provides several updates for the SRv6 implementation. The first patch leverages the existing infrastructure to support encapsulation of IPv4 packets. The second patch implements the T.Encaps.L2 SR function, enabling to encapsulate an L2 Ethernet frame within an IPv6+SRH packet. The last three patches update the seg6local lightweight tunnel, and mainly implement four new actions: End.T, End.DX2, End.DX4 and End.DT6. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-25ipv6: sr: implement additional seg6local actionsDavid Lebrun
This patch implements the following seg6local actions. - SEG6_LOCAL_ACTION_END_T: regular SRH processing and forward to the next-hop looked up in the specified routing table. - SEG6_LOCAL_ACTION_END_DX2: decapsulate an L2 frame and forward it to the specified network interface. - SEG6_LOCAL_ACTION_END_DX4: decapsulate an IPv4 packet and forward it, possibly to the specified next-hop. - SEG6_LOCAL_ACTION_END_DT6: decapsulate an IPv6 packet and forward it to the next-hop looked up in the specified routing table. Signed-off-by: David Lebrun <david.lebrun@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-25ipv6: sr: add helper functions for seg6localDavid Lebrun
This patch adds three helper functions to be used with the seg6local packet processing actions. The decap_and_validate() function will be used by the End.D* actions, that decapsulate an SR-enabled packet. The advance_nextseg() function applies the fundamental operations to update an SRH for the next segment. The lookup_nexthop() function helps select the next-hop for the processed SR packets. It supports an optional next-hop address to route the packet specifically through it, and an optional routing table to use. Signed-off-by: David Lebrun <david.lebrun@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-25ipv6: sr: enforce IPv6 packets for seg6local lwtDavid Lebrun
This patch ensures that the seg6local lightweight tunnel is used solely with IPv6 routes and processes only IPv6 packets. Signed-off-by: David Lebrun <david.lebrun@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-25ipv6: sr: add support for encapsulation of L2 framesDavid Lebrun
This patch implements the L2 frame encapsulation mechanism, referred to as T.Encaps.L2 in the SRv6 specifications [1]. A new type of SRv6 tunnel mode is added (SEG6_IPTUN_MODE_L2ENCAP). It only accepts packets with an existing MAC header (i.e., it will not work for locally generated packets). The resulting packet looks like IPv6 -> SRH -> Ethernet -> original L3 payload. The next header field of the SRH is set to NEXTHDR_NONE. [1] https://tools.ietf.org/html/draft-filsfils-spring-srv6-network-programming-01 Signed-off-by: David Lebrun <david.lebrun@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-25ipv6: sr: add support for ip4ip6 encapsulationDavid Lebrun
This patch enables the SRv6 encapsulation mode to carry an IPv4 payload. All the infrastructure was already present, I just had to add a parameter to seg6_do_srh_encap() to specify the inner packet protocol, and perform some additional checks. Usage example: ip route add 1.2.3.4 encap seg6 mode encap segs fc00::1,fc00::2 dev eth0 Signed-off-by: David Lebrun <david.lebrun@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-25Merge tag 'for-linus-20170825' of git://git.infradead.org/linux-mtdLinus Torvalds
Pull MTD fixes from Brian Norris: "Two fixes - one for a 4.13 regression, and the other for an older one: - Atmel NAND: since we started utilizing ONFI timings, we found that we were being too restrict at rejecting them, partly due to discrepancies in ONFI 4.0 and earlier versions. Relax the restriction to keep these platforms booting. This is a 4.13-rc1 regression. - nandsim: repeated probe/removal may not work after a failed init, because we didn't free up our debugfs files properly on the failure path. This has been around since 3.8, but it's nice to get this fixed now in a nice easy patch that can target -stable, since there's already refactoring work (that also fixes the issue) targeted for the next merge window" * tag 'for-linus-20170825' of git://git.infradead.org/linux-mtd: mtd: nand: atmel: Relax tADL_min constraint mtd: nandsim: remove debugfs entries in error path
2017-08-25ipv6: Fix may be used uninitialized warning in rt6_checkSteffen Klassert
rt_cookie might be used uninitialized, fix this by initializing it. Fixes: c5cff8561d2d ("ipv6: add rcu grace period before freeing fib6_node") Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-25Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fixes from Jens Axboe: "A small batch of fixes that should be included for the 4.13 release. This contains: - Revert of the 4k loop blocksize support. Even with a recent batch of 4 fixes, we're still not really happy with it. Rather than be stuck with an API issue, let's revert it and get it right for 4.14. - Trivial patch from Bart, adding a few flags to the blk-mq debugfs exports that were added in this release, but not to the debugfs parts. - Regression fix for bsg, fixing a potential kernel panic. From Benjamin. - Tweak for the blk throttling, improving how we account discards. From Shaohua" * 'for-linus' of git://git.kernel.dk/linux-block: blk-mq-debugfs: Add names for recently added flags bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer Revert "loop: support 4k physical blocksize" blk-throttle: cap discard request size
2017-08-25Merge branch 'i2c/for-current' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c fixes from Wolfram Sang: "I2C has some bugfixes for you: mainly Jarkko fixed up a few things in the designware driver regarding the new slave mode. But Ulf also fixed a long-standing and now agreed suspend problem. Plus, some simple stuff which nonetheless needs fixing" * 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: i2c: designware: Fix runtime PM for I2C slave mode i2c: designware: Remove needless pm_runtime_put_noidle() call i2c: aspeed: fixed potential null pointer dereference i2c: simtec: use release_mem_region instead of release_resource i2c: core: Make comment about I2C table requirement to reflect the code i2c: designware: Fix standard mode speed when configuring the slave mode i2c: designware: Fix oops from i2c_dw_irq_handler_slave i2c: designware: Fix system suspend
2017-08-25PCI/MSI: Don't warn when irq_create_affinity_masks() returns NULLChristoph Hellwig
irq_create_affinity_masks() can return NULL on non-SMP systems, when there are not enough "free" vectors available to spread, or if memory allocation for the CPU masks fails. Only the allocation failure is of interest, and even then the system will work just fine except for non-optimally spread vectors. Thus remove the warnings. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: David S. Miller <davem@davemloft.net>
2017-08-25Merge tag 'mmc-v4.13-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc Pull MMC fix from Ulf Hansson: "MMC core: don't return error code R1_OUT_OF_RANGE for open-ending mode" * tag 'mmc-v4.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc: mmc: block: prevent propagating R1_OUT_OF_RANGE for open-ending mode
2017-08-25Merge tag 'sound-4.13-rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound Pull sound fixes from Takashi Iwai: "We're keeping in a good shape, this batch contains just a few small fixes (a regression fix for ASoC rt5677 codec, NULL dereference and error-path fixes in firewire, and a corner-case ioctl error fix for user TLV), as well as usual quirks for USB-audio and HD-audio" * tag 'sound-4.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: ASoC: rt5677: Reintroduce I2C device IDs ALSA: hda - Add stereo mic quirk for Lenovo G50-70 (17aa:3978) ALSA: core: Fix unexpected error at replacing user TLV ALSA: usb-audio: Add delay quirk for H650e/Jabra 550a USB headsets ALSA: firewire-motu: destroy stream data surely at failure of card initialization ALSA: firewire: fix NULL pointer dereference when releasing uninitialized data of iso-resource
2017-08-25Merge tag 'dmaengine-fix-4.13-rc7' of ↵Linus Torvalds
git://git.infradead.org/users/vkoul/slave-dma Pull dmaengine fix from Vinod Koul: "A single fix for tegra210-adma driver to check of_irq_get() error" * tag 'dmaengine-fix-4.13-rc7' of git://git.infradead.org/users/vkoul/slave-dma: dmaengine: tegra210-adma: fix of_irq_get() error check
2017-08-25Merge tag 'drm-fixes-for-v4.13-rc7' of ↵Linus Torvalds
git://people.freedesktop.org/~airlied/linux Pull drm fixes from Dave Airlie: "Fixes for rc7, nothing too crazy, some core, i915, and sunxi fixes, Intel CI has been responsible for some of these fixes being required" * tag 'drm-fixes-for-v4.13-rc7' of git://people.freedesktop.org/~airlied/linux: drm/i915/gvt: Fix the kernel null pointer error drm: Release driver tracking before making the object available again drm/i915: Clear lost context-switch interrupts across reset drm/i915/bxt: use NULL for GPIO connection ID drm/i915/cnl: Fix LSPCON support. drm/i915/vbt: ignore extraneous child devices for a port drm/i915: Initialize 'data' in intel_dsi_dcs_backlight.c drm/atomic: If the atomic check fails, return its value first drm/atomic: Handle -EDEADLK with out-fences correctly drm: Fix framebuffer leak drm/imx: ipuv3-plane: fix YUV framebuffer scanout on the base plane gpu: ipu-v3: add DRM dependency drm/rockchip: Fix suspend crash when drm is not bound drm/sun4i: Implement drm_driver lastclose to restore fbdev console
2017-08-25mm/memblock.c: reversed logic in memblock_discard()Pavel Tatashin
In recently introduced memblock_discard() there is a reversed logic bug. Memory is freed of static array instead of dynamically allocated one. Link: http://lkml.kernel.org/r/1503511441-95478-2-git-send-email-pasha.tatashin@oracle.com Fixes: 3010f876500f ("mm: discard memblock data later") Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reported-by: Woody Suwalski <terraluna977@gmail.com> Tested-by: Woody Suwalski <terraluna977@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-25fork: fix incorrect fput of ->exe_file causing use-after-freeEric Biggers
Commit 7c051267931a ("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 a reference is taken on the mm_struct's ->exe_file. Since the ->exe_file of the new mm_struct was already set to the old ->exe_file by the memcpy() in dup_mm(), it was possible for the mmput() in the error path of dup_mm() to drop a reference to ->exe_file which was never taken. This caused the struct file to later be freed prematurely. Fix it by updating mm_init() to NULL out the ->exe_file, in the same place it clears other things like the list of mmaps. This bug was found by syzkaller. It can be reproduced using the following C program: #define _GNU_SOURCE #include <pthread.h> #include <stdlib.h> #include <sys/mman.h> #include <sys/syscall.h> #include <sys/wait.h> #include <unistd.h> static void *mmap_thread(void *_arg) { for (;;) { mmap(NULL, 0x1000000, PROT_READ, MAP_POPULATE|MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); } } static void *fork_thread(void *_arg) { usleep(rand() % 10000); fork(); } int main(void) { fork(); fork(); fork(); for (;;) { if (fork() == 0) { pthread_t t; pthread_create(&t, NULL, mmap_thread, NULL); pthread_create(&t, NULL, fork_thread, NULL); usleep(rand() % 10000); syscall(__NR_exit_group, 0); } wait(NULL); } } No special kernel config options are needed. It usually causes a NULL pointer dereference in __remove_shared_vm_struct() during exit, or in dup_mmap() (which is usually inlined into copy_process()) during fork. Both are due to a vm_area_struct's ->vm_file being used after it's already been freed. Google Bug Id: 64772007 Link: http://lkml.kernel.org/r/20170823211408.31198-1-ebiggers3@gmail.com Fixes: 7c051267931a ("mm, fork: make dup_mmap wait for mmap_sem for write killable") Signed-off-by: Eric Biggers <ebiggers@google.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: <stable@vger.kernel.org> [v4.7+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-25mm/madvise.c: fix freeing of locked page with MADV_FREEEric Biggers
If madvise(..., MADV_FREE) split a transparent hugepage, it called put_page() before unlock_page(). This was wrong because put_page() can free the page, e.g. if a concurrent madvise(..., MADV_DONTNEED) has removed it from the memory mapping. put_page() then rightfully complained about freeing a locked page. Fix this by moving the unlock_page() before put_page(). This bug was found by syzkaller, which encountered the following splat: BUG: Bad page state in process syzkaller412798 pfn:1bd800 page:ffffea0006f60000 count:0 mapcount:0 mapping: (null) index:0x20a00 flags: 0x200000000040019(locked|uptodate|dirty|swapbacked) raw: 0200000000040019 0000000000000000 0000000000020a00 00000000ffffffff raw: ffffea0006f60020 ffffea0006f60020 0000000000000000 0000000000000000 page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set bad because of flags: 0x1(locked) Modules linked in: CPU: 1 PID: 3037 Comm: syzkaller412798 Not tainted 4.13.0-rc5+ #35 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 bad_page+0x230/0x2b0 mm/page_alloc.c:565 free_pages_check_bad+0x1f0/0x2e0 mm/page_alloc.c:943 free_pages_check mm/page_alloc.c:952 [inline] free_pages_prepare mm/page_alloc.c:1043 [inline] free_pcp_prepare mm/page_alloc.c:1068 [inline] free_hot_cold_page+0x8cf/0x12b0 mm/page_alloc.c:2584 __put_single_page mm/swap.c:79 [inline] __put_page+0xfb/0x160 mm/swap.c:113 put_page include/linux/mm.h:814 [inline] madvise_free_pte_range+0x137a/0x1ec0 mm/madvise.c:371 walk_pmd_range mm/pagewalk.c:50 [inline] walk_pud_range mm/pagewalk.c:108 [inline] walk_p4d_range mm/pagewalk.c:134 [inline] walk_pgd_range mm/pagewalk.c:160 [inline] __walk_page_range+0xc3a/0x1450 mm/pagewalk.c:249 walk_page_range+0x200/0x470 mm/pagewalk.c:326 madvise_free_page_range.isra.9+0x17d/0x230 mm/madvise.c:444 madvise_free_single_vma+0x353/0x580 mm/madvise.c:471 madvise_dontneed_free mm/madvise.c:555 [inline] madvise_vma mm/madvise.c:664 [inline] SYSC_madvise mm/madvise.c:832 [inline] SyS_madvise+0x7d3/0x13c0 mm/madvise.c:760 entry_SYSCALL_64_fastpath+0x1f/0xbe Here is a C reproducer: #define _GNU_SOURCE #include <pthread.h> #include <sys/mman.h> #include <unistd.h> #define MADV_FREE 8 #define PAGE_SIZE 4096 static void *mapping; static const size_t mapping_size = 0x1000000; static void *madvise_thrproc(void *arg) { madvise(mapping, mapping_size, (long)arg); } int main(void) { pthread_t t[2]; for (;;) { mapping = mmap(NULL, mapping_size, PROT_WRITE, MAP_POPULATE|MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); munmap(mapping + mapping_size / 2, PAGE_SIZE); pthread_create(&t[0], 0, madvise_thrproc, (void*)MADV_DONTNEED); pthread_create(&t[1], 0, madvise_thrproc, (void*)MADV_FREE); pthread_join(t[0], NULL); pthread_join(t[1], NULL); munmap(mapping, mapping_size); } } Note: to see the splat, CONFIG_TRANSPARENT_HUGEPAGE=y and CONFIG_DEBUG_VM=y are needed. Google Bug Id: 64696096 Link: http://lkml.kernel.org/r/20170823205235.132061-1-ebiggers3@gmail.com Fixes: 854e9ed09ded ("mm: support madvise(MADV_FREE)") Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: <stable@vger.kernel.org> [v4.5+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-25dax: fix deadlock due to misaligned PMD faultsRoss Zwisler
In DAX there are two separate places where the 2MiB range of a PMD is defined. The first is in the page tables, where a PMD mapping inserted for a given address spans from (vmf->address & PMD_MASK) to ((vmf->address & PMD_MASK) + PMD_SIZE - 1). That is, from the 2MiB boundary below the address to the 2MiB boundary above the address. So, for example, a fault at address 3MiB (0x30 0000) falls within the PMD that ranges from 2MiB (0x20 0000) to 4MiB (0x40 0000). The second PMD range is in the mapping->page_tree, where a given file offset is covered by a radix tree entry that spans from one 2MiB aligned file offset to another 2MiB aligned file offset. So, for example, the file offset for 3MiB (pgoff 768) falls within the PMD range for the order 9 radix tree entry that ranges from 2MiB (pgoff 512) to 4MiB (pgoff 1024). This system works so long as the addresses and file offsets for a given mapping both have the same offsets relative to the start of each PMD. Consider the case where the starting address for a given file isn't 2MiB aligned - say our faulting address is 3 MiB (0x30 0000), but that corresponds to the beginning of our file (pgoff 0). Now all the PMDs in the mapping are misaligned so that the 2MiB range defined in the page tables never matches up with the 2MiB range defined in the radix tree. The current code notices this case for DAX faults to storage with the following test in dax_pmd_insert_mapping(): if (pfn_t_to_pfn(pfn) & PG_PMD_COLOUR) goto unlock_fallback; This test makes sure that the pfn we get from the driver is 2MiB aligned, and relies on the assumption that the 2MiB alignment of the pfn we get back from the driver matches the 2MiB alignment of the faulting address. However, faults to holes were not checked and we could hit the problem described above. This was reported in response to the NVML nvml/src/test/pmempool_sync TEST5: $ cd nvml/src/test/pmempool_sync $ make TEST5 You can grab NVML here: https://github.com/pmem/nvml/ The dmesg warning you see when you hit this error is: WARNING: CPU: 13 PID: 2900 at fs/dax.c:641 dax_insert_mapping_entry+0x2df/0x310 Where we notice in dax_insert_mapping_entry() that the radix tree entry we are about to replace doesn't match the locked entry that we had previously inserted into the tree. This happens because the initial insertion was done in grab_mapping_entry() using a pgoff calculated from the faulting address (vmf->address), and the replacement in dax_pmd_load_hole() => dax_insert_mapping_entry() is done using vmf->pgoff. In our failure case those two page offsets (one calculated from vmf->address, one using vmf->pgoff) point to different order 9 radix tree entries. This failure case can result in a deadlock because the radix tree unlock also happens on the pgoff calculated from vmf->address. This means that the locked radix tree entry that we swapped in to the tree in dax_insert_mapping_entry() using vmf->pgoff is never unlocked, so all future faults to that 2MiB range will block forever. Fix this by validating that the faulting address's PMD offset matches the PMD offset from the start of the file. This check is done at the very beginning of the fault and covers faults that would have mapped to storage as well as faults to holes. I left the COLOUR check in dax_pmd_insert_mapping() in place in case we ever hit the insanity condition where the alignment of the pfn we get from the driver doesn't match the alignment of the userspace address. Link: http://lkml.kernel.org/r/20170822222436.18926-1-ross.zwisler@linux.intel.com Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Reported-by: "Slusarz, Marcin" <marcin.slusarz@intel.com> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-25mm, shmem: fix handling /sys/kernel/mm/transparent_hugepage/shmem_enabledKirill A. Shutemov
/sys/kernel/mm/transparent_hugepage/shmem_enabled controls if we want to allocate huge pages when allocate pages for private in-kernel shmem mount. Unfortunately, as Dan noticed, I've screwed it up and the only way to make kernel allocate huge page for the mount is to use "force" there. All other values will be effectively ignored. Link: http://lkml.kernel.org/r/20170822144254.66431-1-kirill.shutemov@linux.intel.com Fixes: 5a6e75f8110c ("shmem: prepare huge= mount option and sysfs knob") Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: stable <stable@vger.kernel.org> [4.8+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-25PM/hibernate: touch NMI watchdog when creating snapshotChen Yu
There is a problem that when counting the pages for creating the hibernation snapshot will take significant amount of time, especially on system with large memory. Since the counting job is performed with irq disabled, this might lead to NMI lockup. The following warning were found on a system with 1.5TB DRAM: Freezing user space processes ... (elapsed 0.002 seconds) done. OOM killer disabled. PM: Preallocating image memory... NMI watchdog: Watchdog detected hard LOCKUP on cpu 27 CPU: 27 PID: 3128 Comm: systemd-sleep Not tainted 4.13.0-0.rc2.git0.1.fc27.x86_64 #1 task: ffff9f01971ac000 task.stack: ffffb1a3f325c000 RIP: 0010:memory_bm_find_bit+0xf4/0x100 Call Trace: swsusp_set_page_free+0x2b/0x30 mark_free_pages+0x147/0x1c0 count_data_pages+0x41/0xa0 hibernate_preallocate_memory+0x80/0x450 hibernation_snapshot+0x58/0x410 hibernate+0x17c/0x310 state_store+0xdf/0xf0 kobj_attr_store+0xf/0x20 sysfs_kf_write+0x37/0x40 kernfs_fop_write+0x11c/0x1a0 __vfs_write+0x37/0x170 vfs_write+0xb1/0x1a0 SyS_write+0x55/0xc0 entry_SYSCALL_64_fastpath+0x1a/0xa5 ... done (allocated 6590003 pages) PM: Allocated 26360012 kbytes in 19.89 seconds (1325.28 MB/s) It has taken nearly 20 seconds(2.10GHz CPU) thus the NMI lockup was triggered. In case the timeout of the NMI watch dog has been set to 1 second, a safe interval should be 6590003/20 = 320k pages in theory. However there might also be some platforms running at a lower frequency, so feed the watchdog every 100k pages. [yu.c.chen@intel.com: simplification] Link: http://lkml.kernel.org/r/1503460079-29721-1-git-send-email-yu.c.chen@intel.com [yu.c.chen@intel.com: use interval of 128k instead of 100k to avoid modulus] Link: http://lkml.kernel.org/r/1503328098-5120-1-git-send-email-yu.c.chen@intel.com Signed-off-by: Chen Yu <yu.c.chen@intel.com> Reported-by: Jan Filipcewicz <jan.filipcewicz@intel.com> Suggested-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Michal Hocko <mhocko@suse.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Len Brown <lenb@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-25i40e: synchronize nvmupdate command and adminq subtaskSudheer Mogilappagari
During NVM update, state machine gets into unrecoverable state because i40e_clean_adminq_subtask can get scheduled after the admin queue command but before other state variables are updated. This causes incorrect input to i40e_nvmupd_check_wait_event and state transitions don't happen. This issue existed before but surfaced after commit 373149fc99a0 ("i40e: Decrease the scope of rtnl lock") This fix adds locking around admin queue command and update of state variables so that adminq_subtask will have accurate information whenever it gets scheduled. Signed-off-by: Sudheer Mogilappagari <sudheer.mogilappagari@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-08-25i40e: prevent changing ITR if adaptive-rx/tx enabledAlan Brady
Currently the driver allows the user to change (or even disable) interrupt moderation if adaptive-rx/tx is enabled when this should not be the case. Adaptive RX/TX will not respect the user's ITR settings so allowing the user to change it is weird. This bug would also allow the user to disable interrupt moderation with adaptive-rx/tx enabled which doesn't make much sense either. This patch makes it such that if adaptive-rx/tx is enabled, the user cannot make any manual adjustments to interrupt moderation. It also makes it so that if ITR is disabled but adaptive-rx/tx is then enabled, ITR will be re-enabled. Signed-off-by: Alan Brady <alan.brady@intel.com> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-08-25i40e: use cpumask_copy instead of direct assignmentJacob Keller
According to the header file cpumask.h, we shouldn't be directly copying a cpumask_t, since its a bitmap and might not be copied correctly. Lets use the provided cpumask_copy() function instead. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-08-25i40evf: use netdev variable in reset taskAlan Brady
If we're going to bother initializing a variable to reference it we might as well use it. Signed-off-by: Alan Brady <alan.brady@intel.com> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-08-25i40e/i40evf: rename vf_offload_flags to vf_cap_flags in struct ↵Stefan Assmann
virtchnl_vf_resource The current name of vf_offload_flags indicates that the bitmap is limited to offload related features. Make this more generic by renaming it to vf_cap_flags, which allows for other capabilities besides offloading to be added. Signed-off-by: Stefan Assmann <sassmann@kpanic.de> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-08-25i40e: move check for avoiding VID=0 filters into i40e_vsi_add_vlanJacob Keller
In i40e_vsi_add_vlan we treat attempting to add VID=0 as an error, because it does not do what the caller might expect. We already special case VID=0 in i40e_vlan_rx_add_vid so that we avoid this error when adding the VLAN. This special casing is necessary so that we do not add the VLAN=0 filter since we don't want to stop receiving untagged traffic. Unfortunately, not all callers of i40e_vsi_add_vlan are aware of this, including when we add VLANs from a VF device. Rather than special casing every single caller of i40e_vsi_add_vlan, lets just move this check internally. This makes the code simpler because the caller does not need to be aware of how VLAN=0 is special, and we don't forget to add this check in new places. This fixes a harmless error message displaying when adding a VLAN from within a VF. The message was meaningless but there is no reason to confuse end users and system administrators, and this is now avoided. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-08-25i40e/i40evf: use cmpxchg64 when updating private flags in ethtoolJacob Keller
When a user gives an invalid command to change a private flag which is not supported, either because it is read-only, or the device is not capable of the feature, we simply ignore the request. A naive solution would simply be to report error codes when one of the flags was not supported. However, this causes problems because it makes the operation not atomic. If a user requests multiple private flags together at once we could end up changing one before failing at the second flag. We can do a bit better if we instead update a temporary copy of the flags variable in the loop, and then copy it into place after. If we aren't careful this has the pitfall of potentially silently overwriting any changes caused by other threads. Avoid this by using cmpxchg64 which will compare and swap the flags variable only if it currently matched the old value. We'll report -EAGAIN in the (hopefully rare!) case where the cmpxchg64 fails. This ensures that we can properly report when flags are not supported in an atomic fashion without the risk of overwriting other threads changes. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-08-25i40e: Detect ATR HW Evict NVM issue and disable the featureAnjali Singhai Jain
This patch fixes a problem with the HW ATR eviction feature where the NVM setting was incorrect. This patch detects the issue on X720 adapters and disables the feature if the NVM setting is incorrect. Without this patch, HW ATR Evict feature does not work on broken NVMs and is not detected either. If the HW ATR Evict feature is disabled the SW Eviction feature will take effect. Signed-off-by: Anjali Singhai Jain <anjali.singhai@intel.com> Signed-off-by: Alice Michael <alice.michael@intel.com> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-08-25i40e: remove workaround for Open Firmware MAC addressJacob Keller
Since commit b499ffb0a22c ("i40e: Look up MAC address in Open Firmware or IDPROM"), we've had support for obtaining the MAC address form Open Firmware or IDPROM. This code relied on sending the Open Firmware address directly to the device firmware instead of relying on our MAC/VLAN filter list. Thus, a work around was introduced in commit b1b15df59232 ("i40e: Explicitly write platform-specific mac address after PF reset") We refactored the Open Firmware address enablement code in the ill-named commit 41c4c2b50d52 ("i40e: allow look-up of MAC address from Open Firmware or IDPROM") Since this refactor, we no longer even set I40E_FLAG_PF_MAC. Further, we don't need this work around, because we actually store the MAC address as part of the MAC/VLAN filter hash. Thus, we will restore the address correctly upon reset. The refactor above failed to revert the workaround, so do that now. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-08-25i40e: separate hw_features from runtime changing flagsJacob Keller
The number of flags found in pf->flags has grown quite large, and there are a lot of different types of flags. Most of the flags are simply hardware features which are enabled on some firmware or some MAC types. Other flags are dynamic run-time flags which enable or disable certain features of the driver. Separate these two types of flags into pf->hw_features and pf->flags. The hw_features list will contain a set of features which are enabled at init time. This will not contain toggles or otherwise dynamically changing features. These flags should not need atomic protections, as they will be set once during init and then be essentially read only. Everything else will remain in the flags variable. These flags may be modified at any time during run time. A future patch may wish to convert these flags into set_bit/clear_bit/test_bit or similar approach to ensure atomic correctness. The I40E_FLAG_MFP_ENABLED flag may be a good fit for hw_features but currently is used by ethtool in the private flags settings, and thus has been left as part of flags. Additionally, I40E_FLAG_DCB_CAPABLE may be a good fit for the hw_features but this patch has not tried to untangle it yet. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-08-25i40e: Fix a bug with VMDq RSS queue allocationAnjali Singhai Jain
The X722 pf flag setup should happen before the VMDq RSS queue count is initialized for VMDq VSI to get the right number of queues for RSS in case of X722 devices. Signed-off-by: Anjali Singhai Jain <anjali.singhai@intel.com> Signed-off-by: Alice Michael <alice.michael@intel.com> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-08-25i40evf: prevent VF close returning before state transitions to DOWNSudheer Mogilappagari
Currently i40evf_close() can return before state transitions to __I40EVF_DOWN because of the latency involved in processing and receiving response from PF driver and scheduling of VF watchdog_task. Due to this inconsistency an immediate call to i40evf_open() fails because state is still DOWN_PENDING. When a VF interface is in up state and we try to add it as slave, The bonding driver calls dev_close() and dev_open() in short duration resulting in dev_open returning error. The ifenslave command needs to be run again for dev_open to succeed. This fix ensures that watchdog timer is scheduled immediately after admin queue operations are scheduled in i40evf_down(). In addition a wait condition is added at the end of i40evf_close so that function wont return when state is still DOWN_PENDING. The timeout value is chosen after some profiling and includes some buffer. Signed-off-by: Sudheer Mogilappagari <sudheer.mogilappagari@intel.com> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-08-25i40e/i40evf: adjust packet size to account for double VLANsMitch Williams
Now that the kernel supports double VLAN tags, we should at least play nice. Adjust the max packet size to account for two VLAN tags, not just one. Signed-off-by: Mitch Williams <mitch.a.williams@intel.com> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2017-08-25xen-blkback: stop blkback thread of every queue in xen_blkif_disconnectAnnie Li
In xen_blkif_disconnect, before checking inflight I/O, following code stops the blkback thread, if (ring->xenblkd) { kthread_stop(ring->xenblkd); wake_up(&ring->shutdown_wq); } If there is inflight I/O in any non-last queue, blkback returns -EBUSY directly, and above code would not be called to stop thread of remaining queue and processs them. When removing vbd device with lots of disk I/O load, some queues with inflight I/O still have blkback thread running even though the corresponding vbd device or guest is gone. And this could cause some problems, for example, if the backend device type is file, some loop devices and blkback thread always lingers there forever after guest is destroyed, and this causes failure of umounting repositories unless rebooting the dom0. This patch allows thread of every queue has the chance to get stopped. Otherwise, only thread of queue previous to(including) first busy one get stopped, blkthread of remaining queue will still run. So stop all threads properly and return -EBUSY if any queue has inflight I/O. Signed-off-by: Annie Li <annie.li@oracle.com> Reviewed-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Reviewed-by: Bhavesh Davda <bhavesh.davda@oracle.com> Reviewed-by: Adnan Misherfi <adnan.misherfi@oracle.com> Acked-by: Roger Pau Monné <roger.pau@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2017-08-25virtio_pci: fix cpu affinity supportChristoph Hellwig
Commit 0b0f9dc5 ("Revert "virtio_pci: use shared interrupts for virtqueues"") removed the adjustment of the pre_vectors for the virtio MSI-X vector allocation which was added in commit fb5e31d9 ("virtio: allow drivers to request IRQ affinity when creating VQs"). This will lead to an incorrect assignment of MSI-X vectors, and potential deadlocks when offlining cpus. Signed-off-by: Christoph Hellwig <hch@lst.de> Fixes: 0b0f9dc5 ("Revert "virtio_pci: use shared interrupts for virtqueues") Reported-by: YASUAKI ISHIMATSU <yasu.isimatu@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-08-25virtio_blk: fix incorrect message when disk is resizedStefan Hajnoczi
The message printed on disk resize is incorrect. The following is printed when resizing to 2 GiB: $ truncate -s 1G test.img $ qemu -device virtio-blk-pci,logical_block_size=4096,... (qemu) block_resize drive1 2G virtio_blk virtio0: new size: 4194304 4096-byte logical blocks (17.2 GB/16.0 GiB) The virtio_blk capacity config field is in 512-byte sector units regardless of logical_block_size as per the VIRTIO specification. Therefore the message should read: virtio_blk virtio0: new size: 524288 4096-byte logical blocks (2.15 GB/2.0 GiB) Note that this only affects the printed message. Thankfully the actual block device has the correct size because the block layer expects capacity in sectors. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-08-25ieee802154: 6lowpan: make header_ops constBhumika Goyal
Make this const as it is only stored as a reference in a const field of a net_device structure. Signed-off-by: Bhumika Goyal <bhumirks@gmail.com> Acked-by: Stefan Schmidt <stefan@osg.samsung.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2017-08-25blk-mq-debugfs: Add names for recently added flagsBart Van Assche
The symbolic constants QUEUE_FLAG_SCSI_PASSTHROUGH, QUEUE_FLAG_QUIESCED and REQ_NOWAIT are missing from blk-mq-debugfs.c. Add these to blk-mq-debugfs.c such that these appear as names in debugfs instead of as numbers. Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Cc: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-25KVM: PPC: Book3S: Fix race and leak in kvm_vm_ioctl_create_spapr_tce()Paul Mackerras
Nixiaoming pointed out that there is a memory leak in kvm_vm_ioctl_create_spapr_tce() if the call to anon_inode_getfd() fails; the memory allocated for the kvmppc_spapr_tce_table struct is not freed, and nor are the pages allocated for the iommu tables. In addition, we have already incremented the process's count of locked memory pages, and this doesn't get restored on error. David Hildenbrand pointed out that there is a race in that the function checks early on that there is not already an entry in the stt->iommu_tables list with the same LIOBN, but an entry with the same LIOBN could get added between then and when the new entry is added to the list. This fixes all three problems. To simplify things, we now call anon_inode_getfd() before placing the new entry in the list. The check for an existing entry is done while holding the kvm->lock mutex, immediately before adding the new entry to the list. Finally, on failure we now call kvmppc_account_memlimit to decrement the process's count of locked memory pages. Reported-by: Nixiaoming <nixiaoming@huawei.com> Reported-by: David Hildenbrand <david@redhat.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-25perf/core: Fix group {cpu,task} validationMark Rutland
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: Mark Rutland <mark.rutland@arm.com> 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> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1498142498-15758-1-git-send-email-mark.rutland@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-25x86/mm: Fix use-after-free of ldt_structEric Biggers
The following commit: 39a0526fb3f7 ("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: 5d17a73a2ebe ("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: Eric Biggers <ebiggers@google.com> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: <stable@vger.kernel.org> [v4.6+] 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: 39a0526fb3f7 ("x86/mm: Factor out LDT init from context init") Link: http://lkml.kernel.org/r/20170824175029.76040-1-ebiggers3@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-25KVM, pkeys: do not use PKRU value in vcpu->arch.guest_fpu.statePaolo Bonzini
The host pkru is restored right after vcpu exit (commit 1be0e61), so KVM_GET_XSAVE will return the host PKRU value instead. Fix this by using the guest PKRU explicitly in fill_xsave and load_xsave. This part is based on a patch by Junkang Fu. The host PKRU data may also not match the value in vcpu->arch.guest_fpu.state, because it could have been changed by userspace since the last time it was saved, so skip loading it in kvm_load_guest_fpu. Reported-by: Junkang Fu <junkang.fjk@alibaba-inc.com> Cc: Yang Zhang <zy107165@alibaba-inc.com> Fixes: 1be0e61c1f255faaeab04a390e00c8b9b9042870 Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-25KVM: x86: simplify handling of PKRUPaolo Bonzini
Move it to struct kvm_arch_vcpu, replacing guest_pkru_valid with a simple comparison against the host value of the register. The write of PKRU in addition can be skipped if the guest has not enabled the feature. Once we do this, we need not test OSPKE in the host anymore, because guest_CR4.PKE=1 implies host_CR4.PKE=1. The static PKU test is kept to elide the code on older CPUs. Suggested-by: Yang Zhang <zy107165@alibaba-inc.com> Fixes: 1be0e61c1f255faaeab04a390e00c8b9b9042870 Cc: stable@vger.kernel.org Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-25KVM: x86: block guest protection keys unless the host has them enabledPaolo Bonzini
If the host has protection keys disabled, we cannot read and write the guest PKRU---RDPKRU and WRPKRU fail with #GP(0) if CR4.PKE=0. Block the PKU cpuid bit in that case. This ensures that guest_CR4.PKE=1 implies host_CR4.PKE=1. Fixes: 1be0e61c1f255faaeab04a390e00c8b9b9042870 Cc: stable@vger.kernel.org Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-25esp: Fix skb tailroom calculationSteffen Klassert
We use skb_availroom to calculate the skb tailroom for the ESP trailer. skb_availroom calculates the tailroom and subtracts this value by reserved_tailroom. However reserved_tailroom is a union with the skb mark. This means that we subtract the tailroom by the skb mark if set. Fix this by using skb_tailroom instead. Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible") Fixes: 03e2a30f6a27 ("esp6: Avoid skb_cow_data whenever possible") Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2017-08-25esp: Fix locking on page fragment allocationSteffen Klassert
We allocate the page fragment for the ESP trailer inside a spinlock, but consume it outside of the lock. This is racy as some other cou could get the same page fragment then. Fix this by consuming the page fragment inside the lock too. Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible") Fixes: 03e2a30f6a27 ("esp6: Avoid skb_cow_data whenever possible") Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2017-08-24netvsc: fix deadlock betwen link status and removalstephen hemminger
There is a deadlock possible when canceling the link status delayed work queue. The removal process is run with RTNL held, and the link status callback is acquring RTNL. Resolve the issue by using trylock and rescheduling. If cancel is in process, that block it from happening. Fixes: 122a5f6410f4 ("staging: hv: use delayed_work for netvsc_send_garp()") Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>