From: Guo Ren Date: Sat, 4 Feb 2023 06:35:31 +0000 (-0500) Subject: riscv: kprobe: Fixup misaligned load text X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=14a2de5c16f3da3fdb28398a5119d6fc911aade3;p=linux.git riscv: kprobe: Fixup misaligned load text [ Upstream commit eb7423273cc9922ee2d05bf660c034d7d515bb91 ] The current kprobe would cause a misaligned load for the probe point. This patch fixup it with two half-word loads instead. Fixes: c22b0bcb1dd0 ("riscv: Add kprobes supported") Signed-off-by: Guo Ren Signed-off-by: Guo Ren Link: https://lore.kernel.org/linux-riscv/878rhig9zj.fsf@all.your.base.are.belong.to.us/ Reported-by: Bjorn Topel Reviewed-by: Björn Töpel Link: https://lore.kernel.org/r/20230204063531.740220-1-guoren@kernel.org Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin --- diff --git a/arch/riscv/kernel/probes/kprobes.c b/arch/riscv/kernel/probes/kprobes.c index b53aa0209e079..7548b1d62509c 100644 --- a/arch/riscv/kernel/probes/kprobes.c +++ b/arch/riscv/kernel/probes/kprobes.c @@ -65,16 +65,18 @@ static bool __kprobes arch_check_kprobe(struct kprobe *p) int __kprobes arch_prepare_kprobe(struct kprobe *p) { - unsigned long probe_addr = (unsigned long)p->addr; + u16 *insn = (u16 *)p->addr; - if (probe_addr & 0x1) + if ((unsigned long)insn & 0x1) return -EILSEQ; if (!arch_check_kprobe(p)) return -EILSEQ; /* copy instruction */ - p->opcode = *p->addr; + p->opcode = (kprobe_opcode_t)(*insn++); + if (GET_INSN_LENGTH(p->opcode) == 4) + p->opcode |= (kprobe_opcode_t)(*insn) << 16; /* decode instruction */ switch (riscv_probe_decode_insn(p->addr, &p->ainsn.api)) {