[PATCH v10 3/9] arm64: add copy_to/from_user to kprobes blacklist

David Long
2016-03-01T03:00:39Z

From: "David A. Long" <dave.long@linaro.org>

Currrently taking exceptions when accessing user data from a kprobe'd
instruction doesn't work. Avoid this situation by blacklisting the relevant
functions.

Signed-off-by: David A. Long <dave.long@linaro.org>
---
arch/arm64/lib/copy_from_user.S | 1 +
arch/arm64/lib/copy_to_user.S | 1 +
2 files changed, 2 insertions(+)

diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S
index 4699cd7..0ac2131 100644
--- a/arch/arm64/lib/copy_from_user.S
+++ b/arch/arm64/lib/copy_from_user.S
@@ -66,6 +66,7 @@
.endm

end .req x5
+ .section .kprobes.text,"ax",%progbits
ENTRY(__copy_from_user)
ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_HAS_PAN, \
CONFIG_ARM64_PAN)
diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S
index 7512bbb..e4eb84c 100644
--- a/arch/arm64/lib/copy_to_user.S
+++ b/arch/arm64/lib/copy_to_user.S
@@ -65,6 +65,7 @@
.endm

end .req x5
+ .section .kprobes.text,"ax",%progbits
ENTRY(__copy_to_user)
ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_HAS_PAN, \
CONFIG_ARM64_PAN)
--
2.5.0