From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Sasha Levin <sashal@kernel.org>, linuxppc-dev@lists.ozlabs.org
Subject: [PATCH AUTOSEL 5.14 70/99] powerpc: Avoid link stack corruption in misc asm functions
Date: Thu, 9 Sep 2021 20:15:29 -0400 [thread overview]
Message-ID: <20210910001558.173296-70-sashal@kernel.org> (raw)
In-Reply-To: <20210910001558.173296-1-sashal@kernel.org>
From: Christophe Leroy <christophe.leroy@csgroup.eu>
[ Upstream commit 33e1402435cb9f3021439a15935ea2dc69ec1844 ]
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
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/powerpc/kernel/misc.S | 2 +-
arch/powerpc/kernel/misc_32.S | 2 +-
arch/powerpc/kernel/misc_64.S | 2 +-
arch/powerpc/kernel/reloc_32.S | 2 +-
arch/powerpc/kexec/relocate_32.S | 12 ++++++------
5 files changed, 10 insertions(+), 10 deletions(-)
diff --git a/arch/powerpc/kernel/misc.S b/arch/powerpc/kernel/misc.S
index 5be96feccb55..fb7de3543c03 100644
--- a/arch/powerpc/kernel/misc.S
+++ b/arch/powerpc/kernel/misc.S
@@ -29,7 +29,7 @@ _GLOBAL(reloc_offset)
li r3, 0
_GLOBAL(add_reloc_offset)
mflr r0
- bl 1f
+ bcl 20,31,$+4
1: mflr r5
PPC_LL r4,(2f-1b)(r5)
subf r5,r4,r5
diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index 39ab15419592..921d4198bfaa 100644
--- a/arch/powerpc/kernel/misc_32.S
+++ b/arch/powerpc/kernel/misc_32.S
@@ -67,7 +67,7 @@ _GLOBAL(reloc_got2)
srwi. r8,r8,2
beqlr
mtctr r8
- bl 1f
+ bcl 20,31,$+4
1: mflr r0
lis r4,1b@ha
addi r4,r4,1b@l
diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
index 4b761a18a74d..d38a019b38e1 100644
--- a/arch/powerpc/kernel/misc_64.S
+++ b/arch/powerpc/kernel/misc_64.S
@@ -255,7 +255,7 @@ _GLOBAL(scom970_write)
* Physical (hardware) cpu id should be in r3.
*/
_GLOBAL(kexec_wait)
- bl 1f
+ bcl 20,31,$+4
1: mflr r5
addi r5,r5,kexec_flag-1b
diff --git a/arch/powerpc/kernel/reloc_32.S b/arch/powerpc/kernel/reloc_32.S
index 10e96f3e22fe..0508c14b4c28 100644
--- a/arch/powerpc/kernel/reloc_32.S
+++ b/arch/powerpc/kernel/reloc_32.S
@@ -30,7 +30,7 @@ R_PPC_RELATIVE = 22
_GLOBAL(relocate)
mflr r0 /* Save our LR */
- bl 0f /* Find our current runtime address */
+ bcl 20,31,$+4 /* Find our current runtime address */
0: mflr r12 /* Make it accessible */
mtlr r0
diff --git a/arch/powerpc/kexec/relocate_32.S b/arch/powerpc/kexec/relocate_32.S
index 61946c19e07c..cf6e52bdf8d8 100644
--- a/arch/powerpc/kexec/relocate_32.S
+++ b/arch/powerpc/kexec/relocate_32.S
@@ -93,7 +93,7 @@ wmmucr:
* Invalidate all the TLB entries except the current entry
* where we are running from
*/
- bl 0f /* Find our address */
+ bcl 20,31,$+4 /* Find our address */
0: mflr r5 /* Make it accessible */
tlbsx r23,0,r5 /* Find entry we are in */
li r4,0 /* Start at TLB entry 0 */
@@ -158,7 +158,7 @@ write_out:
/* Switch to other address space in MSR */
insrwi r9, r7, 1, 26 /* Set MSR[IS] = r7 */
- bl 1f
+ bcl 20,31,$+4
1: mflr r8
addi r8, r8, (2f-1b) /* Find the target offset */
@@ -202,7 +202,7 @@ next_tlb:
li r9,0
insrwi r9, r7, 1, 26 /* Set MSR[IS] = r7 */
- bl 1f
+ bcl 20,31,$+4
1: mflr r8
and r8, r8, r11 /* Get our offset within page */
addi r8, r8, (2f-1b)
@@ -240,7 +240,7 @@ setup_map_47x:
sync
/* Find the entry we are running from */
- bl 2f
+ bcl 20,31,$+4
2: mflr r23
tlbsx r23, 0, r23
tlbre r24, r23, 0 /* TLB Word 0 */
@@ -296,7 +296,7 @@ clear_utlb_entry:
/* Update the msr to the new TS */
insrwi r5, r7, 1, 26
- bl 1f
+ bcl 20,31,$+4
1: mflr r6
addi r6, r6, (2f-1b)
@@ -355,7 +355,7 @@ write_utlb:
/* Defaults to 256M */
lis r10, 0x1000
- bl 1f
+ bcl 20,31,$+4
1: mflr r4
addi r4, r4, (2f-1b) /* virtual address of 2f */
--
2.30.2
next prev parent reply other threads:[~2021-09-10 0:20 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20210910001558.173296-1-sashal@kernel.org>
2021-09-10 0:14 ` [PATCH AUTOSEL 5.14 31/99] cpuidle: pseries: Do not cap the CEDE0 latency in fixup_cede0_latency() Sasha Levin
2021-09-10 0:14 ` [PATCH AUTOSEL 5.14 32/99] powerpc: make the install target not depend on any build artifact Sasha Levin
2021-09-10 0:14 ` [PATCH AUTOSEL 5.14 37/99] powerpc: Always inline radix_enabled() to fix build failure Sasha Levin
2021-09-10 0:14 ` [PATCH AUTOSEL 5.14 38/99] KVM: PPC: Book3S HV: XICS: Fix mapping of passthrough interrupts Sasha Levin
2021-09-10 5:48 ` Cédric Le Goater
2021-09-11 14:35 ` Sasha Levin
2021-09-13 16:19 ` Cédric Le Goater
2021-09-10 0:15 ` [PATCH AUTOSEL 5.14 68/99] powerpc/32: indirect function call use bctrl rather than blrl in ret_from_kernel_thread Sasha Levin
2021-09-10 0:15 ` [PATCH AUTOSEL 5.14 69/99] powerpc/booke: Avoid link stack corruption in several places Sasha Levin
2021-09-10 0:15 ` Sasha Levin [this message]
2021-09-10 0:15 ` [PATCH AUTOSEL 5.14 71/99] KVM: PPC: Book3S HV: Initialise vcpu MSR with MSR_ME Sasha Levin
2021-09-10 0:15 ` [PATCH AUTOSEL 5.14 72/99] KVM: PPC: Book3S HV P9: Fixes for TM softpatch interrupt NIP Sasha Levin
2021-09-10 0:15 ` [PATCH AUTOSEL 5.14 73/99] KVM: PPC: Book3S HV Nested: Fix TM softpatch HFAC interrupt emulation Sasha Levin
2021-09-10 0:15 ` [PATCH AUTOSEL 5.14 78/99] powerpc/pseries/iommu: Allow DDW windows starting at 0x00 Sasha Levin
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