* [PATCH] powerpc/32s: fix allow/prevent_user_access() when crossing segment boundaries.
@ 2019-10-14 16:51 Christophe Leroy
2019-10-20 9:09 ` Michael Ellerman
0 siblings, 1 reply; 2+ messages in thread
From: Christophe Leroy @ 2019-10-14 16:51 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
Make sure starting addr is aligned to segment boundary so that when
incrementing the segment, the starting address of the new segment is
below the end address. Otherwise the last segment might get missed.
Fixes: a68c31fc01ef ("powerpc/32s: Implement Kernel Userspace Access Protection")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
arch/powerpc/include/asm/book3s/32/kup.h | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/powerpc/include/asm/book3s/32/kup.h b/arch/powerpc/include/asm/book3s/32/kup.h
index 677e9babef80..f9dc597b0b86 100644
--- a/arch/powerpc/include/asm/book3s/32/kup.h
+++ b/arch/powerpc/include/asm/book3s/32/kup.h
@@ -91,6 +91,7 @@
static inline void kuap_update_sr(u32 sr, u32 addr, u32 end)
{
+ addr &= 0xf0000000; /* align addr to start of segment */
barrier(); /* make sure thread.kuap is updated before playing with SRs */
while (addr < end) {
mtsrin(sr, addr);
--
2.13.3
^ permalink raw reply related [flat|nested] 2+ messages in thread
end of thread, other threads:[~2019-10-20 9:11 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-10-14 16:51 [PATCH] powerpc/32s: fix allow/prevent_user_access() when crossing segment boundaries Christophe Leroy
2019-10-20 9:09 ` Michael Ellerman
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).