From deb60015096102f9842b631dcad98a05001268e9 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Mon, 18 Mar 2013 17:03:03 -0700 Subject: [PATCH] Fix broken fsys_getppid() In particular fsys_getppid always returns the ppid in the initial pid namespace so it does not work for a process in a pid namespace. Fix from Eric Biederman just removes the fast system call path. While it is a little bit sad to see another one of these bite the dust ... I can't imagine that getppid() is really on any real applications critical path. Signed-off-by: Tony Luck --- arch/ia64/kernel/fsys.S | 49 +---------------------------------------- 1 file changed, 1 insertion(+), 48 deletions(-) diff --git a/arch/ia64/kernel/fsys.S b/arch/ia64/kernel/fsys.S index c4cd45d97749..abc6dee3799c 100644 --- a/arch/ia64/kernel/fsys.S +++ b/arch/ia64/kernel/fsys.S @@ -90,53 +90,6 @@ ENTRY(fsys_getpid) FSYS_RETURN END(fsys_getpid) -ENTRY(fsys_getppid) - .prologue - .altrp b6 - .body - add r17=IA64_TASK_GROUP_LEADER_OFFSET,r16 - ;; - ld8 r17=[r17] // r17 = current->group_leader - add r9=TI_FLAGS+IA64_TASK_SIZE,r16 - ;; - - ld4 r9=[r9] - add r17=IA64_TASK_REAL_PARENT_OFFSET,r17 // r17 = ¤t->group_leader->real_parent - ;; - and r9=TIF_ALLWORK_MASK,r9 - -1: ld8 r18=[r17] // r18 = current->group_leader->real_parent - ;; - cmp.ne p8,p0=0,r9 - add r8=IA64_TASK_TGID_OFFSET,r18 // r8 = ¤t->group_leader->real_parent->tgid - ;; - - /* - * The .acq is needed to ensure that the read of tgid has returned its data before - * we re-check "real_parent". - */ - ld4.acq r8=[r8] // r8 = current->group_leader->real_parent->tgid -#ifdef CONFIG_SMP - /* - * Re-read current->group_leader->real_parent. - */ - ld8 r19=[r17] // r19 = current->group_leader->real_parent -(p8) br.spnt.many fsys_fallback_syscall - ;; - cmp.ne p6,p0=r18,r19 // did real_parent change? - mov r19=0 // i must not leak kernel bits... -(p6) br.cond.spnt.few 1b // yes -> redo the read of tgid and the check - ;; - mov r17=0 // i must not leak kernel bits... - mov r18=0 // i must not leak kernel bits... -#else - mov r17=0 // i must not leak kernel bits... - mov r18=0 // i must not leak kernel bits... - mov r19=0 // i must not leak kernel bits... -#endif - FSYS_RETURN -END(fsys_getppid) - ENTRY(fsys_set_tid_address) .prologue .altrp b6 @@ -614,7 +567,7 @@ paravirt_fsyscall_table: data8 0 // chown data8 0 // lseek // 1040 data8 fsys_getpid // getpid - data8 fsys_getppid // getppid + data8 0 // getppid data8 0 // mount data8 0 // umount data8 0 // setuid // 1045 -- 2.34.1