From: Danny Feng <dfeng@redhat.com>
Date: Thu, 21 Jan 2010 11:05:38 -0500
Subject: [x86_64] wire up compat sched_rr_get_interval
Message-id: <20100121110632.3386.15481.sendpatchset@dhcp-65-180.nay.redhat.com>
Patchwork-id: 22689
O-Subject: [PATCH RHEL5.5] x86-64: wire up compat sched_rr_get_interval(2)
Bugzilla: 557092
RH-Acked-by: Amerigo Wang <amwang@redhat.com>
RH-Acked-by: Jarod Wilson <jarod@redhat.com>

RHBZ#:
https://bugzilla.redhat.com/show_bug.cgi?id=557092

Description:
  There is a user data corruption because of a system call in the 32-bit
compatibility mode on the x86_64 system.

  If a program that calls sched_rr_get_interval() was compiled on x86 and is
executed on x86_64, the user stack will be destroyed.

  The kernel fills the data beyond the end of timespec structure because the
size of the structure is different between x86 and x86_64.

Upstream status:
commit a9bc3bf swithes to sys32_sched_rr_get_interval in x86_64 32bit compat
syscall entry.

Brew build:
https://brewweb.devel.redhat.com/taskinfo?taskID=2216763

KABI:
no harm

Test status:
The reproducer works with the patch applied.

diff --git a/arch/x86_64/ia32/ia32entry-xen.S b/arch/x86_64/ia32/ia32entry-xen.S
index 14cca33..1f5d8ee 100644
--- a/arch/x86_64/ia32/ia32entry-xen.S
+++ b/arch/x86_64/ia32/ia32entry-xen.S
@@ -599,7 +599,7 @@ ia32_sys_call_table:
 	.quad sys_sched_yield
 	.quad sys_sched_get_priority_max
 	.quad sys_sched_get_priority_min  /* 160 */
-	.quad sys_sched_rr_get_interval
+	.quad sys32_sched_rr_get_interval
 	.quad compat_sys_nanosleep
 	.quad sys_mremap
 	.quad sys_setresuid16
diff --git a/arch/x86_64/ia32/ia32entry.S b/arch/x86_64/ia32/ia32entry.S
index ebfc581..175ac6b 100644
--- a/arch/x86_64/ia32/ia32entry.S
+++ b/arch/x86_64/ia32/ia32entry.S
@@ -566,7 +566,7 @@ ia32_sys_call_table:
 	.quad sys_sched_yield
 	.quad sys_sched_get_priority_max
 	.quad sys_sched_get_priority_min  /* 160 */
-	.quad sys_sched_rr_get_interval
+	.quad sys32_sched_rr_get_interval
 	.quad compat_sys_nanosleep
 	.quad sys_mremap
 	.quad sys_setresuid16