https://github.com/torvalds/linux
Revision 655548bf6271b212cd1e4c259da9dbe616348d38 authored by Kirill A. Shutemov on 30 November 2016, 23:54:05 UTC, committed by Linus Torvalds on 01 December 2016, 00:32:52 UTC
The following program triggers BUG() in munlock_vma_pages_range(): // autogenerated by syzkaller (http://github.com/google/syzkaller) #include <sys/mman.h> int main() { mmap((void*)0x20105000ul, 0xc00000ul, 0x2ul, 0x2172ul, -1, 0); mremap((void*)0x201fd000ul, 0x4000ul, 0xc00000ul, 0x3ul, 0x203f0000ul); return 0; } The test-case constructs the situation when munlock_vma_pages_range() finds PTE-mapped THP-head in the middle of page table and, by mistake, skips HPAGE_PMD_NR pages after that. As result, on the next iteration it hits the middle of PMD-mapped THP and gets upset seeing mlocked tail page. The solution is only skip HPAGE_PMD_NR pages if the THP was mlocked during munlock_vma_page(). It would guarantee that the page is PMD-mapped as we never mlock PTE-mapeed THPs. Fixes: e90309c9f772 ("thp: allow mlocked THP again") Link: http://lkml.kernel.org/r/20161115132703.7s7rrgmwttegcdh4@black.fi.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: syzkaller <syzkaller@googlegroups.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: <stable@vger.kernel.org> [4.5+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Tip revision: 655548bf6271b212cd1e4c259da9dbe616348d38 authored by Kirill A. Shutemov on 30 November 2016, 23:54:05 UTC
thp: fix corner case of munlock() of PTE-mapped THPs
thp: fix corner case of munlock() of PTE-mapped THPs
Tip revision: 655548b
File | Mode | Size |
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Kconfig | -rw-r--r-- | 3.8 KB |
Kconfig.iosched | -rw-r--r-- | 1.6 KB |
Makefile | -rw-r--r-- | 949 bytes |
badblocks.c | -rw-r--r-- | 14.5 KB |
bio-integrity.c | -rw-r--r-- | 14.2 KB |
bio.c | -rw-r--r-- | 48.5 KB |
blk-cgroup.c | -rw-r--r-- | 35.8 KB |
blk-core.c | -rw-r--r-- | 93.3 KB |
blk-exec.c | -rw-r--r-- | 3.2 KB |
blk-flush.c | -rw-r--r-- | 16.3 KB |
blk-integrity.c | -rw-r--r-- | 12.3 KB |
blk-ioc.c | -rw-r--r-- | 10.2 KB |
blk-lib.c | -rw-r--r-- | 7.3 KB |
blk-map.c | -rw-r--r-- | 5.8 KB |
blk-merge.c | -rw-r--r-- | 19.6 KB |
blk-mq-cpumap.c | -rw-r--r-- | 2.3 KB |
blk-mq-pci.c | -rw-r--r-- | 1.5 KB |
blk-mq-sysfs.c | -rw-r--r-- | 11.7 KB |
blk-mq-tag.c | -rw-r--r-- | 11.1 KB |
blk-mq-tag.h | -rw-r--r-- | 2.2 KB |
blk-mq.c | -rw-r--r-- | 56.5 KB |
blk-mq.h | -rw-r--r-- | 2.7 KB |
blk-settings.c | -rw-r--r-- | 27.0 KB |
blk-softirq.c | -rw-r--r-- | 4.3 KB |
blk-sysfs.c | -rw-r--r-- | 18.5 KB |
blk-tag.c | -rw-r--r-- | 10.0 KB |
blk-throttle.c | -rw-r--r-- | 42.7 KB |
blk-timeout.c | -rw-r--r-- | 5.9 KB |
blk.h | -rw-r--r-- | 9.0 KB |
bounce.c | -rw-r--r-- | 5.8 KB |
bsg-lib.c | -rw-r--r-- | 6.0 KB |
bsg.c | -rw-r--r-- | 22.9 KB |
cfq-iosched.c | -rw-r--r-- | 127.1 KB |
cmdline-parser.c | -rw-r--r-- | 4.9 KB |
compat_ioctl.c | -rw-r--r-- | 20.8 KB |
deadline-iosched.c | -rw-r--r-- | 11.3 KB |
elevator.c | -rw-r--r-- | 23.8 KB |
genhd.c | -rw-r--r-- | 45.0 KB |
ioctl.c | -rw-r--r-- | 14.8 KB |
ioprio.c | -rw-r--r-- | 5.1 KB |
noop-iosched.c | -rw-r--r-- | 2.6 KB |
partition-generic.c | -rw-r--r-- | 14.7 KB |
scsi_ioctl.c | -rw-r--r-- | 19.4 KB |
t10-pi.c | -rw-r--r-- | 4.8 KB |
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