From c9e34f92dafffe1fd37ba7ef7fb198002576bea1 Mon Sep 17 00:00:00 2001 From: Nagappan Ramasamy Palaniappan Date: Wed, 2 Aug 2023 12:54:02 +0000 Subject: [PATCH 2/5] prlimit: do_prlimit needs to have a speculation check CVE: CVE-2023-0458 commit 739790605705ddcf18f21782b9c99ad7d53a8c11 Author: Greg Kroah-Hartman Date: Fri Jan 20 11:03:20 2023 +0100 prlimit: do_prlimit needs to have a speculation check 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 Tested-by: Jordy Zomer Suggested-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman Signed-off-by: Nagappan Ramasamy Palaniappan Reviewed-by: Laurence Rochfort --- kernel/sys.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/sys.c b/kernel/sys.c index 75852f64d..45480f6f6 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1439,6 +1439,8 @@ static 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; -- 2.31.1