https://github.com/torvalds/linux
Revision cb185d5f1ebf900f4ae3bf84cee212e6dd035aca authored by Nadav Amit on 18 October 2021, 22:15:25 UTC, committed by Linus Torvalds on 19 October 2021, 06:22:02 UTC
A race is possible when a process exits, its VMAs are removed by exit_mmap() and at the same time userfaultfd_writeprotect() is called. The race was detected by KASAN on a development kernel, but it appears to be possible on vanilla kernels as well. Use mmget_not_zero() to prevent the race as done in other userfaultfd operations. Link: https://lkml.kernel.org/r/20210921200247.25749-1-namit@vmware.com Fixes: 63b2d4174c4ad ("userfaultfd: wp: add the writeprotect API to userfaultfd ioctl") Signed-off-by: Nadav Amit <namit@vmware.com> Tested-by: Li Wang <liwang@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 8913970
Tip revision: cb185d5f1ebf900f4ae3bf84cee212e6dd035aca authored by Nadav Amit on 18 October 2021, 22:15:25 UTC
userfaultfd: fix a race between writeprotect and exit_mmap()
userfaultfd: fix a race between writeprotect and exit_mmap()
Tip revision: cb185d5
File | Mode | Size |
---|---|---|
damon | ||
kasan | ||
kfence | ||
Kconfig | -rw-r--r-- | 28.3 KB |
Kconfig.debug | -rw-r--r-- | 5.6 KB |
Makefile | -rw-r--r-- | 4.7 KB |
backing-dev.c | -rw-r--r-- | 27.3 KB |
balloon_compaction.c | -rw-r--r-- | 8.2 KB |
bootmem_info.c | -rw-r--r-- | 3.4 KB |
cleancache.c | -rw-r--r-- | 9.8 KB |
cma.c | -rw-r--r-- | 15.4 KB |
cma.h | -rw-r--r-- | 1.4 KB |
cma_debug.c | -rw-r--r-- | 4.5 KB |
cma_sysfs.c | -rw-r--r-- | 2.4 KB |
compaction.c | -rw-r--r-- | 83.5 KB |
debug.c | -rw-r--r-- | 8.2 KB |
debug_page_ref.c | -rw-r--r-- | 1.4 KB |
debug_vm_pgtable.c | -rw-r--r-- | 38.0 KB |
dmapool.c | -rw-r--r-- | 13.6 KB |
early_ioremap.c | -rw-r--r-- | 6.7 KB |
fadvise.c | -rw-r--r-- | 5.3 KB |
failslab.c | -rw-r--r-- | 1.4 KB |
filemap.c | -rw-r--r-- | 111.4 KB |
frontswap.c | -rw-r--r-- | 14.2 KB |
gup.c | -rw-r--r-- | 86.0 KB |
gup_test.c | -rw-r--r-- | 5.6 KB |
gup_test.h | -rw-r--r-- | 938 bytes |
highmem.c | -rw-r--r-- | 19.4 KB |
hmm.c | -rw-r--r-- | 16.7 KB |
huge_memory.c | -rw-r--r-- | 85.5 KB |
hugetlb.c | -rw-r--r-- | 176.8 KB |
hugetlb_cgroup.c | -rw-r--r-- | 21.5 KB |
hugetlb_vmemmap.c | -rw-r--r-- | 13.0 KB |
hugetlb_vmemmap.h | -rw-r--r-- | 1.1 KB |
hwpoison-inject.c | -rw-r--r-- | 2.6 KB |
init-mm.c | -rw-r--r-- | 1.6 KB |
internal.h | -rw-r--r-- | 20.8 KB |
interval_tree.c | -rw-r--r-- | 3.1 KB |
io-mapping.c | -rw-r--r-- | 993 bytes |
ioremap.c | -rw-r--r-- | 1.2 KB |
khugepaged.c | -rw-r--r-- | 59.3 KB |
kmemleak.c | -rw-r--r-- | 56.5 KB |
ksm.c | -rw-r--r-- | 88.4 KB |
list_lru.c | -rw-r--r-- | 14.1 KB |
maccess.c | -rw-r--r-- | 9.1 KB |
madvise.c | -rw-r--r-- | 32.4 KB |
mapping_dirty_helpers.c | -rw-r--r-- | 10.5 KB |
memblock.c | -rw-r--r-- | 60.1 KB |
memcontrol.c | -rw-r--r-- | 192.2 KB |
memfd.c | -rw-r--r-- | 7.9 KB |
memory-failure.c | -rw-r--r-- | 58.9 KB |
memory.c | -rw-r--r-- | 148.3 KB |
memory_hotplug.c | -rw-r--r-- | 66.2 KB |
mempolicy.c | -rw-r--r-- | 74.9 KB |
mempool.c | -rw-r--r-- | 15.9 KB |
memremap.c | -rw-r--r-- | 14.4 KB |
memtest.c | -rw-r--r-- | 2.8 KB |
migrate.c | -rw-r--r-- | 85.7 KB |
mincore.c | -rw-r--r-- | 7.0 KB |
mlock.c | -rw-r--r-- | 22.4 KB |
mm_init.c | -rw-r--r-- | 5.3 KB |
mmap.c | -rw-r--r-- | 101.7 KB |
mmap_lock.c | -rw-r--r-- | 6.2 KB |
mmu_gather.c | -rw-r--r-- | 8.5 KB |
mmu_notifier.c | -rw-r--r-- | 35.0 KB |
mmzone.c | -rw-r--r-- | 2.2 KB |
mprotect.c | -rw-r--r-- | 17.7 KB |
mremap.c | -rw-r--r-- | 27.8 KB |
msync.c | -rw-r--r-- | 2.8 KB |
nommu.c | -rw-r--r-- | 44.5 KB |
oom_kill.c | -rw-r--r-- | 31.5 KB |
page-writeback.c | -rw-r--r-- | 86.7 KB |
page_alloc.c | -rw-r--r-- | 262.5 KB |
page_counter.c | -rw-r--r-- | 6.8 KB |
page_ext.c | -rw-r--r-- | 11.1 KB |
page_idle.c | -rw-r--r-- | 5.2 KB |
page_io.c | -rw-r--r-- | 11.2 KB |
page_isolation.c | -rw-r--r-- | 9.2 KB |
page_owner.c | -rw-r--r-- | 15.9 KB |
page_poison.c | -rw-r--r-- | 2.5 KB |
page_reporting.c | -rw-r--r-- | 10.3 KB |
page_reporting.h | -rw-r--r-- | 1.6 KB |
page_vma_mapped.c | -rw-r--r-- | 8.7 KB |
pagewalk.c | -rw-r--r-- | 15.5 KB |
percpu-internal.h | -rw-r--r-- | 6.6 KB |
percpu-km.c | -rw-r--r-- | 3.2 KB |
percpu-stats.c | -rw-r--r-- | 5.9 KB |
percpu-vm.c | -rw-r--r-- | 11.7 KB |
percpu.c | -rw-r--r-- | 100.9 KB |
pgalloc-track.h | -rw-r--r-- | 1.3 KB |
pgtable-generic.c | -rw-r--r-- | 5.6 KB |
process_vm_access.c | -rw-r--r-- | 8.2 KB |
ptdump.c | -rw-r--r-- | 4.0 KB |
readahead.c | -rw-r--r-- | 19.5 KB |
rmap.c | -rw-r--r-- | 67.9 KB |
rodata_test.c | -rw-r--r-- | 1.3 KB |
secretmem.c | -rw-r--r-- | 5.5 KB |
shmem.c | -rw-r--r-- | 107.8 KB |
shuffle.c | -rw-r--r-- | 4.7 KB |
shuffle.h | -rw-r--r-- | 1.2 KB |
slab.c | -rw-r--r-- | 106.5 KB |
slab.h | -rw-r--r-- | 17.3 KB |
slab_common.c | -rw-r--r-- | 33.3 KB |
slob.c | -rw-r--r-- | 18.2 KB |
slub.c | -rw-r--r-- | 152.8 KB |
sparse-vmemmap.c | -rw-r--r-- | 15.7 KB |
sparse.c | -rw-r--r-- | 26.0 KB |
swap.c | -rw-r--r-- | 31.6 KB |
swap_cgroup.c | -rw-r--r-- | 5.1 KB |
swap_slots.c | -rw-r--r-- | 9.2 KB |
swap_state.c | -rw-r--r-- | 24.0 KB |
swapfile.c | -rw-r--r-- | 96.4 KB |
truncate.c | -rw-r--r-- | 25.0 KB |
usercopy.c | -rw-r--r-- | 9.5 KB |
userfaultfd.c | -rw-r--r-- | 17.6 KB |
util.c | -rw-r--r-- | 26.6 KB |
vmacache.c | -rw-r--r-- | 2.7 KB |
vmalloc.c | -rw-r--r-- | 100.2 KB |
vmpressure.c | -rw-r--r-- | 13.8 KB |
vmscan.c | -rw-r--r-- | 133.4 KB |
vmstat.c | -rw-r--r-- | 54.2 KB |
workingset.c | -rw-r--r-- | 21.4 KB |
z3fold.c | -rw-r--r-- | 47.0 KB |
zbud.c | -rw-r--r-- | 18.4 KB |
zpool.c | -rw-r--r-- | 11.5 KB |
zsmalloc.c | -rw-r--r-- | 61.0 KB |
zswap.c | -rw-r--r-- | 38.9 KB |
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