* bug in arm_kprobe_decode_insn
@ 2011-02-20 18:24 ` Marcin Slusarz
0 siblings, 0 replies; 4+ messages in thread
From: Marcin Slusarz @ 2011-02-20 18:24 UTC (permalink / raw)
To: linux-arm-kernel; +Cc: Quentin Barnes, Nicolas Pitre, LKML
Hi
In arch/arm/kernel/kprobes-decode.c there's a function arm_kprobe_decode_insn
which does:
} else if ((insn & 0x0e000000) == 0x0c400000) {
...
This is always false, so code below is dead.
I'm not sure about what was intended here, but I think this change might be correct:
diff --git a/arch/arm/kernel/kprobes-decode.c b/arch/arm/kernel/kprobes-decode.c
index 2c1f005..8f6ed43 100644
--- a/arch/arm/kernel/kprobes-decode.c
+++ b/arch/arm/kernel/kprobes-decode.c
@@ -1437,7 +1437,7 @@ arm_kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi)
return space_cccc_1100_010x(insn, asi);
- } else if ((insn & 0x0e000000) == 0x0c400000) {
+ } else if ((insn & 0x0e000000) == 0x0c000000) {
return space_cccc_110x(insn, asi);
--
I found this bug by coccinelle (http://coccinelle.lip6.fr/).
(The script is ugly, so I'm not attaching it here)
Marcin Slusarz
^ permalink raw reply related [flat|nested] 4+ messages in thread
* bug in arm_kprobe_decode_insn
@ 2011-02-20 18:24 ` Marcin Slusarz
0 siblings, 0 replies; 4+ messages in thread
From: Marcin Slusarz @ 2011-02-20 18:24 UTC (permalink / raw)
To: linux-arm-kernel
Hi
In arch/arm/kernel/kprobes-decode.c there's a function arm_kprobe_decode_insn
which does:
} else if ((insn & 0x0e000000) == 0x0c400000) {
...
This is always false, so code below is dead.
I'm not sure about what was intended here, but I think this change might be correct:
diff --git a/arch/arm/kernel/kprobes-decode.c b/arch/arm/kernel/kprobes-decode.c
index 2c1f005..8f6ed43 100644
--- a/arch/arm/kernel/kprobes-decode.c
+++ b/arch/arm/kernel/kprobes-decode.c
@@ -1437,7 +1437,7 @@ arm_kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi)
return space_cccc_1100_010x(insn, asi);
- } else if ((insn & 0x0e000000) == 0x0c400000) {
+ } else if ((insn & 0x0e000000) == 0x0c000000) {
return space_cccc_110x(insn, asi);
--
I found this bug by coccinelle (http://coccinelle.lip6.fr/).
(The script is ugly, so I'm not attaching it here)
Marcin Slusarz
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: bug in arm_kprobe_decode_insn
2011-02-20 18:24 ` Marcin Slusarz
@ 2011-02-21 3:41 ` Nicolas Pitre
-1 siblings, 0 replies; 4+ messages in thread
From: Nicolas Pitre @ 2011-02-21 3:41 UTC (permalink / raw)
To: Marcin Slusarz; +Cc: linux-arm-kernel, Quentin Barnes, LKML
On Sun, 20 Feb 2011, Marcin Slusarz wrote:
> Hi
>
> In arch/arm/kernel/kprobes-decode.c there's a function arm_kprobe_decode_insn
> which does:
>
> } else if ((insn & 0x0e000000) == 0x0c400000) {
> ...
>
> This is always false, so code below is dead.
Good catch, thanks.
Nicolas
^ permalink raw reply [flat|nested] 4+ messages in thread
* bug in arm_kprobe_decode_insn
@ 2011-02-21 3:41 ` Nicolas Pitre
0 siblings, 0 replies; 4+ messages in thread
From: Nicolas Pitre @ 2011-02-21 3:41 UTC (permalink / raw)
To: linux-arm-kernel
On Sun, 20 Feb 2011, Marcin Slusarz wrote:
> Hi
>
> In arch/arm/kernel/kprobes-decode.c there's a function arm_kprobe_decode_insn
> which does:
>
> } else if ((insn & 0x0e000000) == 0x0c400000) {
> ...
>
> This is always false, so code below is dead.
Good catch, thanks.
Nicolas
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2011-02-21 3:41 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2011-02-20 18:24 bug in arm_kprobe_decode_insn Marcin Slusarz
2011-02-20 18:24 ` Marcin Slusarz
2011-02-21 3:41 ` Nicolas Pitre
2011-02-21 3:41 ` Nicolas Pitre
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