[PATCH 4.9 10/56] ARM: 8731/1: Fix csum_partial_copy_from_user() stack mismatch

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

--

From: Chunyan Zhang 


[ Upstream commit 36b0cb84ee858f02c256d26f0cb4229c78e3399e ]

An additional 'ip' will be pushed to the stack, for restoring the
DACR later, if CONFIG_CPU_SW_DOMAIN_PAN defined.

However, the fixup still get the err_ptr by add #8*4 to sp, which
results in the fact that the code area pointed by the LR will be
overwritten, or the kernel will crash if CONFIG_DEBUG_RODATA is enabled.

This patch fixes the stack mismatch.

Fixes: a5e090acbf54 ("ARM: software-based priviledged-no-access support")
Signed-off-by: Lvqiang Huang 
Signed-off-by: Chunyan Zhang 
Signed-off-by: Russell King 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman 
---
 arch/arm/lib/csumpartialcopyuser.S |4 
 1 file changed, 4 insertions(+)

--- a/arch/arm/lib/csumpartialcopyuser.S
+++ b/arch/arm/lib/csumpartialcopyuser.S
@@ -85,7 +85,11 @@
.pushsection .text.fixup,"ax"
.align  4
 9001:  mov r4, #-EFAULT
+#ifdef CONFIG_CPU_SW_DOMAIN_PAN
+   ldr r5, [sp, #9*4]  @ *err_ptr
+#else
ldr r5, [sp, #8*4]  @ *err_ptr
+#endif
str r4, [r5]
ldmia   sp, {r1, r2}@ retrieve dst, len
add r2, r2, r1

[PATCH 4.9 10/56] ARM: 8731/1: Fix csum_partial_copy_from_user() stack mismatch

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

--

From: Chunyan Zhang 


[ Upstream commit 36b0cb84ee858f02c256d26f0cb4229c78e3399e ]

An additional 'ip' will be pushed to the stack, for restoring the
DACR later, if CONFIG_CPU_SW_DOMAIN_PAN defined.

However, the fixup still get the err_ptr by add #8*4 to sp, which
results in the fact that the code area pointed by the LR will be
overwritten, or the kernel will crash if CONFIG_DEBUG_RODATA is enabled.

This patch fixes the stack mismatch.

Fixes: a5e090acbf54 ("ARM: software-based priviledged-no-access support")
Signed-off-by: Lvqiang Huang 
Signed-off-by: Chunyan Zhang 
Signed-off-by: Russell King 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman 
---
 arch/arm/lib/csumpartialcopyuser.S |4 
 1 file changed, 4 insertions(+)

--- a/arch/arm/lib/csumpartialcopyuser.S
+++ b/arch/arm/lib/csumpartialcopyuser.S
@@ -85,7 +85,11 @@
.pushsection .text.fixup,"ax"
.align  4
 9001:  mov r4, #-EFAULT
+#ifdef CONFIG_CPU_SW_DOMAIN_PAN
+   ldr r5, [sp, #9*4]  @ *err_ptr
+#else
ldr r5, [sp, #8*4]  @ *err_ptr
+#endif
str r4, [r5]
ldmia   sp, {r1, r2}@ retrieve dst, len
add r2, r2, r1