3.18-stable review patch. If anyone has any objections, please let me know.
------------------ From: zhongjiang <[email protected]> commit dd83c161fbcc5d8be637ab159c0de015cbff5ba4 upstream. wait4(-2147483648, 0x20, 0, 0xdd0000) triggers: UBSAN: Undefined behaviour in kernel/exit.c:1651:9 The related calltrace is as follows: negation of -2147483648 cannot be represented in type 'int': CPU: 9 PID: 16482 Comm: zj Tainted: G B ---- ------- 3.10.0-327.53.58.71.x86_64+ #66 Hardware name: Huawei Technologies Co., Ltd. Tecal RH2285 /BC11BTSA , BIOS CTSAV036 04/27/2011 Call Trace: dump_stack+0x19/0x1b ubsan_epilogue+0xd/0x50 __ubsan_handle_negate_overflow+0x109/0x14e SyS_wait4+0x1cb/0x1e0 system_call_fastpath+0x16/0x1b Exclude the overflow to avoid the UBSAN warning. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: zhongjiang <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: David Rientjes <[email protected]> Cc: Aneesh Kumar K.V <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Xishi Qiu <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- kernel/exit.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/kernel/exit.c +++ b/kernel/exit.c @@ -1620,6 +1620,10 @@ SYSCALL_DEFINE4(wait4, pid_t, upid, int __WNOTHREAD|__WCLONE|__WALL)) return -EINVAL; + /* -INT_MIN is not defined */ + if (upid == INT_MIN) + return -ESRCH; + if (upid == -1) type = PIDTYPE_MAX; else if (upid < 0) {
