[PATCH v3 1/4] arm64: kprobes: Move extable address check into arch_prepare_kprobe()

From: Masami Hiramatsu
Date: Tue Feb 12 2019 - 10:43:48 EST


Move extable address check into arch_prepare_kprobe() from
arch_within_kprobe_blacklist().
The blacklist is exposed via debugfs as a list of symbols.
The extable entries are smaller, so must be filtered out
by arch_prepare_kprobe().

Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Reviewed-by: James Morse <james.morse@xxxxxxx>
---
Update in v2:
- Update commit message.
- Add Reviewed-by from James.
---
arch/arm64/kernel/probes/kprobes.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c
index f17afb99890c..9989ec9baa11 100644
--- a/arch/arm64/kernel/probes/kprobes.c
+++ b/arch/arm64/kernel/probes/kprobes.c
@@ -102,6 +102,10 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p)

if (in_exception_text(probe_addr))
return -EINVAL;
+
+ if (search_exception_tables(probe_addr))
+ return -EINVAL;
+
if (probe_addr >= (unsigned long) __start_rodata &&
probe_addr <= (unsigned long) __end_rodata)
return -EINVAL;
@@ -479,8 +483,7 @@ bool arch_within_kprobe_blacklist(unsigned long addr)
(addr >= (unsigned long)__idmap_text_start &&
addr < (unsigned long)__idmap_text_end) ||
(addr >= (unsigned long)__hyp_text_start &&
- addr < (unsigned long)__hyp_text_end) ||
- !!search_exception_tables(addr))
+ addr < (unsigned long)__hyp_text_end))
return true;

if (!is_kernel_in_hyp_mode()) {