Revision a4aeaa06d45e90f9b279f0b09de84bd00006e733 authored by Yang Shi on 28 October 2021, 21:36:30 UTC, committed by Linus Torvalds on 29 October 2021, 00:18:55 UTC
The read-only THP for filesystems will collapse THP for files opened readonly and mapped with VM_EXEC. The intended usecase is to avoid TLB misses for large text segments. But it doesn't restrict the file types so a THP could be collapsed for a non-regular file, for example, block device, if it is opened readonly and mapped with EXEC permission. This may cause bugs, like [1] and [2]. This is definitely not the intended usecase, so just collapse THP for regular files in order to close the attack surface. [shy828301@gmail.com: fix vm_file check [3]] Link: https://lore.kernel.org/lkml/CACkBjsYwLYLRmX8GpsDpMthagWOjWWrNxqY6ZLNQVr6yx+f5vA@mail.gmail.com/ [1] Link: https://lore.kernel.org/linux-mm/000000000000c6a82505ce284e4c@google.com/ [2] Link: https://lkml.kernel.org/r/CAHbLzkqTW9U3VvTu1Ki5v_cLRC9gHW+znBukg_ycergE0JWj-A@mail.gmail.com [3] Link: https://lkml.kernel.org/r/20211027195221.3825-1-shy828301@gmail.com Fixes: 99cb0dbd47a1 ("mm,thp: add read-only THP support for (non-shmem) FS") Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Yang Shi <shy828301@gmail.com> Reported-by: Hao Sun <sunhao.th@gmail.com> Reported-by: syzbot+aae069be1de40fb11825@syzkaller.appspotmail.com Cc: Matthew Wilcox <willy@infradead.org> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Song Liu <songliubraving@fb.com> Cc: Andrea Righi <andrea.righi@canonical.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 74c42e1
File | Mode | Size |
---|---|---|
partitions | ||
Kconfig | -rw-r--r-- | 6.6 KB |
Kconfig.iosched | -rw-r--r-- | 1.3 KB |
Makefile | -rw-r--r-- | 1.7 KB |
badblocks.c | -rw-r--r-- | 14.1 KB |
bdev.c | -rw-r--r-- | 26.9 KB |
bfq-cgroup.c | -rw-r--r-- | 38.7 KB |
bfq-iosched.c | -rw-r--r-- | 255.3 KB |
bfq-iosched.h | -rw-r--r-- | 37.4 KB |
bfq-wf2q.c | -rw-r--r-- | 52.7 KB |
bio-integrity.c | -rw-r--r-- | 12.3 KB |
bio.c | -rw-r--r-- | 47.3 KB |
blk-cgroup-rwstat.c | -rw-r--r-- | 3.4 KB |
blk-cgroup-rwstat.h | -rw-r--r-- | 3.9 KB |
blk-cgroup.c | -rw-r--r-- | 49.9 KB |
blk-core.c | -rw-r--r-- | 47.2 KB |
blk-crypto-fallback.c | -rw-r--r-- | 18.5 KB |
blk-crypto-internal.h | -rw-r--r-- | 5.4 KB |
blk-crypto.c | -rw-r--r-- | 11.9 KB |
blk-exec.c | -rw-r--r-- | 3.0 KB |
blk-flush.c | -rw-r--r-- | 15.3 KB |
blk-integrity.c | -rw-r--r-- | 11.9 KB |
blk-ioc.c | -rw-r--r-- | 10.1 KB |
blk-iocost.c | -rw-r--r-- | 96.4 KB |
blk-iolatency.c | -rw-r--r-- | 28.0 KB |
blk-ioprio.c | -rw-r--r-- | 6.4 KB |
blk-ioprio.h | -rw-r--r-- | 332 bytes |
blk-lib.c | -rw-r--r-- | 11.5 KB |
blk-map.c | -rw-r--r-- | 14.1 KB |
blk-merge.c | -rw-r--r-- | 30.2 KB |
blk-mq-cpumap.c | -rw-r--r-- | 2.2 KB |
blk-mq-debugfs-zoned.c | -rw-r--r-- | 435 bytes |
blk-mq-debugfs.c | -rw-r--r-- | 24.9 KB |
blk-mq-debugfs.h | -rw-r--r-- | 2.7 KB |
blk-mq-pci.c | -rw-r--r-- | 1.3 KB |
blk-mq-rdma.c | -rw-r--r-- | 1.3 KB |
blk-mq-sched.c | -rw-r--r-- | 18.1 KB |
blk-mq-sched.h | -rw-r--r-- | 2.5 KB |
blk-mq-sysfs.c | -rw-r--r-- | 7.0 KB |
blk-mq-tag.c | -rw-r--r-- | 17.7 KB |
blk-mq-tag.h | -rw-r--r-- | 2.6 KB |
blk-mq-virtio.c | -rw-r--r-- | 1.3 KB |
blk-mq.c | -rw-r--r-- | 100.2 KB |
blk-mq.h | -rw-r--r-- | 10.1 KB |
blk-pm.c | -rw-r--r-- | 6.8 KB |
blk-pm.h | -rw-r--r-- | 763 bytes |
blk-rq-qos.c | -rw-r--r-- | 7.0 KB |
blk-rq-qos.h | -rw-r--r-- | 5.3 KB |
blk-settings.c | -rw-r--r-- | 28.4 KB |
blk-stat.c | -rw-r--r-- | 4.8 KB |
blk-stat.h | -rw-r--r-- | 4.6 KB |
blk-sysfs.c | -rw-r--r-- | 24.5 KB |
blk-throttle.c | -rw-r--r-- | 68.5 KB |
blk-timeout.c | -rw-r--r-- | 4.1 KB |
blk-wbt.c | -rw-r--r-- | 19.9 KB |
blk-wbt.h | -rw-r--r-- | 2.8 KB |
blk-zoned.c | -rw-r--r-- | 17.0 KB |
blk.h | -rw-r--r-- | 11.9 KB |
bounce.c | -rw-r--r-- | 6.7 KB |
bsg-lib.c | -rw-r--r-- | 10.0 KB |
bsg.c | -rw-r--r-- | 6.1 KB |
disk-events.c | -rw-r--r-- | 12.9 KB |
elevator.c | -rw-r--r-- | 19.0 KB |
fops.c | -rw-r--r-- | 15.2 KB |
genhd.c | -rw-r--r-- | 35.1 KB |
holder.c | -rw-r--r-- | 4.2 KB |
ioctl.c | -rw-r--r-- | 15.8 KB |
ioprio.c | -rw-r--r-- | 5.1 KB |
keyslot-manager.c | -rw-r--r-- | 16.3 KB |
kyber-iosched.c | -rw-r--r-- | 27.9 KB |
mq-deadline.c | -rw-r--r-- | 30.1 KB |
opal_proto.h | -rw-r--r-- | 9.4 KB |
sed-opal.c | -rw-r--r-- | 62.5 KB |
t10-pi.c | -rw-r--r-- | 7.7 KB |
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...