From 1f55176763a6556916d4c41c80eba7c69d5d3e5a Mon Sep 17 00:00:00 2001 From: Mateusz Guzik Date: Mon, 27 Jan 2014 17:07:11 -0800 Subject: [PATCH] ipc: fix compat msgrcv with negative msgtyp commit e7ca2552369c1dfe0216c626baf82c3d83ec36bb upstream. Compat function takes msgtyp argument as u32 and passes it down to do_msgrcv which results in casting to long, thus the sign is lost and we get a big positive number instead. Cast the argument to signed type before passing it down. Signed-off-by: Mateusz Guzik Reported-by: Gabriellla Schmidt Cc: Al Viro Cc: Davidlohr Bueso Cc: Manfred Spraul Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Cc: Masanari Iida Signed-off-by: Greg Kroah-Hartman --- ipc/compat.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/ipc/compat.c b/ipc/compat.c index 892f6585dd60..d3b376025e9b 100644 --- a/ipc/compat.c +++ b/ipc/compat.c @@ -381,7 +381,7 @@ COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second, uptr = compat_ptr(ipck.msgp); fifth = ipck.msgtyp; } - return do_msgrcv(first, uptr, second, fifth, third, + return do_msgrcv(first, uptr, second, (s32)fifth, third, compat_do_msg_fill); } case MSGGET: -- 2.20.1