On Tue, Jan 24, 2023 at 08:41:30AM -0500, Sasha Levin wrote:
From: Greg Kroah-Hartman gregkh@linuxfoundation.org
[ Upstream commit 739790605705ddcf18f21782b9c99ad7d53a8c11 ]
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: Sasha Levin sashal@kernel.org
kernel/sys.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/kernel/sys.c b/kernel/sys.c index 5fd54bf0e886..88b31f096fb2 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1442,6 +1442,8 @@ 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;
-- 2.39.0
This is already in the 6.1.8 release so no need to add it again :)
thanks,
greg k-h