summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorPaul Mackerras <paulus@samba.org>2005-12-20 15:38:47 +1100
committerPaul Mackerras <paulus@samba.org>2005-12-20 15:38:47 +1100
commit3eb6f26bcd0d2ce53498deda988e68d663e1c9c2 (patch)
tree2e52267600ebfe1f97cbab822143197d0a9edaa3
parent7116317dc9148d783846299fc80a7d377baa6dca (diff)
downloadlinux-stable-3eb6f26bcd0d2ce53498deda988e68d663e1c9c2.tar.gz
linux-stable-3eb6f26bcd0d2ce53498deda988e68d663e1c9c2.tar.bz2
linux-stable-3eb6f26bcd0d2ce53498deda988e68d663e1c9c2.zip
powerpc: correct register usage in 64-bit syscall exit path
Since we don't restore the volatile registers in the syscall exit path, we need to make sure we don't leak any potentially interesting values from the kernel to userspace. This was already the case for all except r11. This makes it use r11 for an MSR value, so r11 will have an (uninteresting) MSR value in it on return to userspace. Signed-off-by: Paul Mackerras <paulus@samba.org>
-rw-r--r--arch/powerpc/kernel/entry_64.S4
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 2d22bf03484e..bce33a38399f 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -183,8 +183,8 @@ syscall_exit_trace_cont:
ld r13,GPR13(r1) /* returning to usermode */
1: ld r2,GPR2(r1)
li r12,MSR_RI
- andc r10,r10,r12
- mtmsrd r10,1 /* clear MSR.RI */
+ andc r11,r10,r12
+ mtmsrd r11,1 /* clear MSR.RI */
ld r1,GPR1(r1)
mtlr r4
mtcr r5