From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> stable inclusion from stable-v4.19.271 commit d3ee91e50a6b3c5a45398e3dcb912a8a264f575c category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I6DPF8 CVE: NA -------------------------------- commit 739790605705ddcf18f21782b9c99ad7d53a8c11 upstream. do_prlimit() adds the user-controlled resource value to a pointer that will subsequently be dereferenced. In order to help prevent this codepath from being used as a spectre "gadget" a barrier needs to be added after checking the range. Reported-by: Jordy Zomer <jordyzomer@google.com> Tested-by: Jordy Zomer <jordyzomer@google.com> Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com> --- kernel/sys.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/sys.c b/kernel/sys.c index faef6e6b635f..b088b71732b7 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1530,6 +1530,8 @@ int do_prlimit(struct task_struct *tsk, unsigned int resource, if (resource >= RLIM_NLIMITS) return -EINVAL; + resource = array_index_nospec(resource, RLIM_NLIMITS); + if (new_rlim) { if (new_rlim->rlim_cur > new_rlim->rlim_max) return -EINVAL; -- 2.25.1