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authorChristophe Leroy <christophe.leroy@csgroup.eu>2021-08-24 10:56:35 +0300
committerMichael Ellerman <mpe@ellerman.id.au>2021-08-25 06:35:47 +0300
commit33e1402435cb9f3021439a15935ea2dc69ec1844 (patch)
treeaa036b96b414c8702dc8ea8d835d5bdbbfec561f /arch/powerpc/kernel/misc_32.S
parentf5007dbf4da729baa850b33a64dc3cc53757bdf8 (diff)
downloadlinux-33e1402435cb9f3021439a15935ea2dc69ec1844.tar.xz
powerpc: Avoid link stack corruption in misc asm functions
bl;mflr is used at several places to get code position. Use bcl 20,31,+4 instead of bl in order to preserve link stack. See commit c974809a26a1 ("powerpc/vdso: Avoid link stack corruption in __get_datapage()") for details. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c6eabb4fb6c156f75d56dcbcc6f243e5ac0fba42.1629791763.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch/powerpc/kernel/misc_32.S')
-rw-r--r--arch/powerpc/kernel/misc_32.S2
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index d8645efff902..e5127b19fec2 100644
--- a/arch/powerpc/kernel/misc_32.S
+++ b/arch/powerpc/kernel/misc_32.S
@@ -67,7 +67,7 @@ _GLOBAL(reloc_got2)
srwi. r8,r8,2
beqlr
mtctr r8
- bl 1f
+ bcl 20,31,$+4
1: mflr r0
lis r4,1b@ha
addi r4,r4,1b@l