3.16.55-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Li Jinyue <[email protected]> commit fbe0e839d1e22d88810f3ee3e2f1479be4c0aa4a upstream. UBSAN reports signed integer overflow in kernel/futex.c: UBSAN: Undefined behaviour in kernel/futex.c:2041:18 signed integer overflow: 0 - -2147483648 cannot be represented in type 'int' Add a sanity check to catch negative values of nr_wake and nr_requeue. Signed-off-by: Li Jinyue <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <[email protected]> --- kernel/futex.c | 3 +++ 1 file changed, 3 insertions(+) --- a/kernel/futex.c +++ b/kernel/futex.c @@ -1531,6 +1531,9 @@ static int futex_requeue(u32 __user *uad struct futex_hash_bucket *hb1, *hb2; struct futex_q *this, *next; + if (nr_wake < 0 || nr_requeue < 0) + return -EINVAL; + if (requeue_pi) { /* * Requeue PI only works on two distinct uaddrs. This

