[PATCH 26/29] csky: kprobe: fix code in simulate without 'long'

From: guoren
Date: Thu Jan 21 2021 - 02:11:04 EST


From: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>

The type of 'val' is 'unsigned long' in simulate_blz32, so 'val < 0'
can't be true.

Cast 'val' to 'long' here to determine branch token or not,

Fixup instructions: bnezad32, bhsz32, bhz32, blsz32, blz32

Link: https://lore.kernel.org/linux-csky/CAJF2gTQjKXR9gpo06WAWG1aquiT87mATiMGorXs6ChxOxoe90Q@xxxxxxxxxxxxxx/T/#t
Signed-off-by: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>
Co-developed-by: Menglong Dong <dong.menglong@xxxxxxxxxx>
Signed-off-by: Menglong Dong <dong.menglong@xxxxxxxxxx>
---
arch/csky/kernel/probes/simulate-insn.c | 22 +++++++---------------
1 file changed, 7 insertions(+), 15 deletions(-)

diff --git a/arch/csky/kernel/probes/simulate-insn.c b/arch/csky/kernel/probes/simulate-insn.c
index 4e464fed52ec..d6e8d092c9b7 100644
--- a/arch/csky/kernel/probes/simulate-insn.c
+++ b/arch/csky/kernel/probes/simulate-insn.c
@@ -274,9 +274,9 @@ void __kprobes
simulate_bnezad32(u32 opcode, long addr, struct pt_regs *regs)
{
unsigned long tmp = opcode & 0x1f;
- unsigned long val;
+ long val;

- csky_insn_reg_get_val(regs, tmp, &val);
+ csky_insn_reg_get_val(regs, tmp, (unsigned long *)&val);

val -= 1;

@@ -286,7 +286,7 @@ simulate_bnezad32(u32 opcode, long addr, struct pt_regs *regs)
} else
instruction_pointer_set(regs, addr + 4);

- csky_insn_reg_set_val(regs, tmp, val);
+ csky_insn_reg_set_val(regs, tmp, (unsigned long)val);
}

void __kprobes
@@ -297,13 +297,11 @@ simulate_bhsz32(u32 opcode, long addr, struct pt_regs *regs)

csky_insn_reg_get_val(regs, tmp, &val);

- if (val >= 0) {
+ if ((long) val >= 0) {
instruction_pointer_set(regs,
addr + sign_extend32((opcode & 0xffff0000) >> 15, 15));
} else
instruction_pointer_set(regs, addr + 4);
-
- csky_insn_reg_set_val(regs, tmp, val);
}

void __kprobes
@@ -314,13 +312,11 @@ simulate_bhz32(u32 opcode, long addr, struct pt_regs *regs)

csky_insn_reg_get_val(regs, tmp, &val);

- if (val > 0) {
+ if ((long) val > 0) {
instruction_pointer_set(regs,
addr + sign_extend32((opcode & 0xffff0000) >> 15, 15));
} else
instruction_pointer_set(regs, addr + 4);
-
- csky_insn_reg_set_val(regs, tmp, val);
}

void __kprobes
@@ -331,13 +327,11 @@ simulate_blsz32(u32 opcode, long addr, struct pt_regs *regs)

csky_insn_reg_get_val(regs, tmp, &val);

- if (val <= 0) {
+ if ((long) val <= 0) {
instruction_pointer_set(regs,
addr + sign_extend32((opcode & 0xffff0000) >> 15, 15));
} else
instruction_pointer_set(regs, addr + 4);
-
- csky_insn_reg_set_val(regs, tmp, val);
}

void __kprobes
@@ -348,13 +342,11 @@ simulate_blz32(u32 opcode, long addr, struct pt_regs *regs)

csky_insn_reg_get_val(regs, tmp, &val);

- if (val < 0) {
+ if ((long) val < 0) {
instruction_pointer_set(regs,
addr + sign_extend32((opcode & 0xffff0000) >> 15, 15));
} else
instruction_pointer_set(regs, addr + 4);
-
- csky_insn_reg_set_val(regs, tmp, val);
}

void __kprobes
--
2.17.1