iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

powerpc/powermac: Fix low_sleep_handler with KUAP and KUEP

Browse Source 
commit 2c637d2df4ee4830e9d3eb2bd5412250522ce96e upstream.

low_sleep_handler() has an hardcoded restore of segment registers
that doesn't take KUAP and KUEP into account.

Use head_32's load_segment_registers() routine instead.

Fixes: a68c31fc01ef ("powerpc/32s: Implement Kernel Userspace Access Protection")
Fixes: 31ed2b13c48d ("powerpc/32s: Implement Kernel Userspace Execution Prevention.")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/21b05f7298c1b18f73e6e5b4cd5005aafa24b6da.1599820109.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Christophe Leroy 2020-09-11 10:29:15 +00:00 committed by Greg Kroah-Hartman
parent 61ed8c1b94
commit 94e27f1369
2 changed files with 2 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/powerpc/kernel/head_32.S
View File

@ -843,7 +843,7 @@ BEGIN_MMU_FTR_SECTION
END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
blr
load_segment_registers:
_GLOBAL(load_segment_registers)
li r0, NUM_USER_SEGMENTS /* load up user segment register values */
mtctr r0 /* for context 0 */
li r3, 0 /* Kp = 0, Ks = 0, VSID = 0 */

9
arch/powerpc/platforms/powermac/sleep.S
View File

@ -293,14 +293,7 @@ grackle_wake_up:
* we do any r1 memory access as we are not sure they
* are in a sane state above the first 256Mb region
*/
li r0,16 /* load up segment register values */
mtctr r0 /* for context 0 */
lis r3,0x2000 /* Ku = 1, VSID = 0 */
li r4,0
3: mtsrin r3,r4
addi r3,r3,0x111 /* increment VSID */
addis r4,r4,0x1000 /* address of next segment */
bdnz 3b
bl load_segment_registers
sync
isync