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>
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File | Mode | Size |
---|---|---|
bpf | ||
cgroup | ||
configs | ||
debug | ||
dma | ||
entry | ||
events | ||
gcov | ||
irq | ||
kcsan | ||
livepatch | ||
locking | ||
power | ||
printk | ||
rcu | ||
sched | ||
time | ||
trace | ||
.gitignore | -rw-r--r-- | 67 bytes |
Kconfig.freezer | -rw-r--r-- | 92 bytes |
Kconfig.hz | -rw-r--r-- | 1.7 KB |
Kconfig.locks | -rw-r--r-- | 4.9 KB |
Kconfig.preempt | -rw-r--r-- | 4.4 KB |
Makefile | -rw-r--r-- | 5.2 KB |
acct.c | -rw-r--r-- | 15.4 KB |
async.c | -rw-r--r-- | 9.3 KB |
audit.c | -rw-r--r-- | 63.5 KB |
audit.h | -rw-r--r-- | 10.4 KB |
audit_fsnotify.c | -rw-r--r-- | 5.2 KB |
audit_tree.c | -rw-r--r-- | 25.5 KB |
audit_watch.c | -rw-r--r-- | 13.7 KB |
auditfilter.c | -rw-r--r-- | 34.1 KB |
auditsc.c | -rw-r--r-- | 71.7 KB |
backtracetest.c | -rw-r--r-- | 1.9 KB |
bounds.c | -rw-r--r-- | 751 bytes |
capability.c | -rw-r--r-- | 14.8 KB |
cfi.c | -rw-r--r-- | 8.1 KB |
compat.c | -rw-r--r-- | 6.8 KB |
configs.c | -rw-r--r-- | 2.0 KB |
context_tracking.c | -rw-r--r-- | 6.4 KB |
cpu.c | -rw-r--r-- | 65.0 KB |
cpu_pm.c | -rw-r--r-- | 6.1 KB |
crash_core.c | -rw-r--r-- | 11.6 KB |
crash_dump.c | -rw-r--r-- | 1.1 KB |
cred.c | -rw-r--r-- | 24.4 KB |
delayacct.c | -rw-r--r-- | 5.4 KB |
dma.c | -rw-r--r-- | 3.3 KB |
exec_domain.c | -rw-r--r-- | 1.1 KB |
exit.c | -rw-r--r-- | 44.8 KB |
extable.c | -rw-r--r-- | 4.4 KB |
fail_function.c | -rw-r--r-- | 7.0 KB |
fork.c | -rw-r--r-- | 77.7 KB |
freezer.c | -rw-r--r-- | 4.4 KB |
futex.c | -rw-r--r-- | 116.7 KB |
gen_kheaders.sh | -rwxr-xr-x | 3.1 KB |
groups.c | -rw-r--r-- | 4.8 KB |
hung_task.c | -rw-r--r-- | 7.5 KB |
iomem.c | -rw-r--r-- | 4.7 KB |
irq_work.c | -rw-r--r-- | 4.9 KB |
jump_label.c | -rw-r--r-- | 21.4 KB |
kallsyms.c | -rw-r--r-- | 21.9 KB |
kcmp.c | -rw-r--r-- | 5.4 KB |
kcov.c | -rw-r--r-- | 27.7 KB |
kexec.c | -rw-r--r-- | 7.4 KB |
kexec_core.c | -rw-r--r-- | 31.2 KB |
kexec_elf.c | -rw-r--r-- | 11.4 KB |
kexec_file.c | -rw-r--r-- | 33.4 KB |
kexec_internal.h | -rw-r--r-- | 924 bytes |
kheaders.c | -rw-r--r-- | 1.6 KB |
kmod.c | -rw-r--r-- | 5.0 KB |
kprobes.c | -rw-r--r-- | 67.4 KB |
ksysfs.c | -rw-r--r-- | 6.3 KB |
kthread.c | -rw-r--r-- | 40.2 KB |
latencytop.c | -rw-r--r-- | 7.2 KB |
module-internal.h | -rw-r--r-- | 782 bytes |
module.c | -rw-r--r-- | 120.3 KB |
module_signature.c | -rw-r--r-- | 1.1 KB |
module_signing.c | -rw-r--r-- | 1.1 KB |
notifier.c | -rw-r--r-- | 15.8 KB |
nsproxy.c | -rw-r--r-- | 12.8 KB |
padata.c | -rw-r--r-- | 27.4 KB |
panic.c | -rw-r--r-- | 18.2 KB |
params.c | -rw-r--r-- | 23.1 KB |
pid.c | -rw-r--r-- | 17.1 KB |
pid_namespace.c | -rw-r--r-- | 11.3 KB |
profile.c | -rw-r--r-- | 15.0 KB |
ptrace.c | -rw-r--r-- | 37.5 KB |
range.c | -rw-r--r-- | 3.0 KB |
reboot.c | -rw-r--r-- | 21.5 KB |
regset.c | -rw-r--r-- | 1.9 KB |
relay.c | -rw-r--r-- | 30.0 KB |
resource.c | -rw-r--r-- | 48.1 KB |
resource_kunit.c | -rw-r--r-- | 4.3 KB |
rseq.c | -rw-r--r-- | 10.3 KB |
scftorture.c | -rw-r--r-- | 19.7 KB |
scs.c | -rw-r--r-- | 2.8 KB |
seccomp.c | -rw-r--r-- | 61.9 KB |
signal.c | -rw-r--r-- | 122.2 KB |
smp.c | -rw-r--r-- | 33.5 KB |
smpboot.c | -rw-r--r-- | 11.7 KB |
smpboot.h | -rw-r--r-- | 640 bytes |
softirq.c | -rw-r--r-- | 23.5 KB |
stackleak.c | -rw-r--r-- | 3.6 KB |
stacktrace.c | -rw-r--r-- | 9.6 KB |
static_call.c | -rw-r--r-- | 12.5 KB |
stop_machine.c | -rw-r--r-- | 17.8 KB |
sys.c | -rw-r--r-- | 63.1 KB |
sys_ni.c | -rw-r--r-- | 10.1 KB |
sysctl-test.c | -rw-r--r-- | 10.7 KB |
sysctl.c | -rw-r--r-- | 81.1 KB |
task_work.c | -rw-r--r-- | 4.6 KB |
taskstats.c | -rw-r--r-- | 15.2 KB |
test_kprobes.c | -rw-r--r-- | 5.9 KB |
torture.c | -rw-r--r-- | 25.3 KB |
tracepoint.c | -rw-r--r-- | 20.3 KB |
tsacct.c | -rw-r--r-- | 4.7 KB |
ucount.c | -rw-r--r-- | 8.8 KB |
uid16.c | -rw-r--r-- | 5.1 KB |
uid16.h | -rw-r--r-- | 442 bytes |
umh.c | -rw-r--r-- | 15.1 KB |
up.c | -rw-r--r-- | 1.5 KB |
user-return-notifier.c | -rw-r--r-- | 1.3 KB |
user.c | -rw-r--r-- | 5.9 KB |
user_namespace.c | -rw-r--r-- | 35.3 KB |
usermode_driver.c | -rw-r--r-- | 4.3 KB |
utsname.c | -rw-r--r-- | 3.8 KB |
utsname_sysctl.c | -rw-r--r-- | 3.2 KB |
watch_queue.c | -rw-r--r-- | 16.4 KB |
watchdog.c | -rw-r--r-- | 20.1 KB |
watchdog_hld.c | -rw-r--r-- | 7.7 KB |
workqueue.c | -rw-r--r-- | 168.2 KB |
workqueue_internal.h | -rw-r--r-- | 2.4 KB |
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