[PATCH 1/4] x86/alternative: Print unadorned pointers

From: Borislav Petkov
Date: Fri Jan 26 2018 - 07:13:01 EST


From: Borislav Petkov <bp@xxxxxxx>

After commit

ad67b74d2469 ("printk: hash addresses printed with %p")

pointers are being hashed when printed. However, this makes the
alternative debug output completely useless. Switch to %px in order to
see the unadorned kernel pointers.

Signed-off-by: Borislav Petkov <bp@xxxxxxx>
---
arch/x86/kernel/alternative.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 4817d743c263..30571fdaaf6f 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -298,7 +298,7 @@ recompute_jump(struct alt_instr *a, u8 *orig_insn, u8 *repl_insn, u8 *insnbuf)
tgt_rip = next_rip + o_dspl;
n_dspl = tgt_rip - orig_insn;

- DPRINTK("target RIP: %p, new_displ: 0x%x", tgt_rip, n_dspl);
+ DPRINTK("target RIP: %px, new_displ: 0x%x", tgt_rip, n_dspl);

if (tgt_rip - orig_insn >= 0) {
if (n_dspl - 2 <= 127)
@@ -355,7 +355,7 @@ static void __init_or_module noinline optimize_nops(struct alt_instr *a, u8 *ins
add_nops(instr + (a->instrlen - a->padlen), a->padlen);
local_irq_restore(flags);

- DUMP_BYTES(instr, a->instrlen, "%p: [%d:%d) optimized NOPs: ",
+ DUMP_BYTES(instr, a->instrlen, "%px: [%d:%d) optimized NOPs: ",
instr, a->instrlen - a->padlen, a->padlen);
}

@@ -376,7 +376,7 @@ void __init_or_module noinline apply_alternatives(struct alt_instr *start,
u8 *instr, *replacement;
u8 insnbuf[MAX_PATCH_LEN];

- DPRINTK("alt table %p -> %p", start, end);
+ DPRINTK("alt table %px, -> %px", start, end);
/*
* The scan order should be from start to end. A later scanned
* alternative code can overwrite previously scanned alternative code.
@@ -400,14 +400,14 @@ void __init_or_module noinline apply_alternatives(struct alt_instr *start,
continue;
}

- DPRINTK("feat: %d*32+%d, old: (%p, len: %d), repl: (%p, len: %d), pad: %d",
+ DPRINTK("feat: %d*32+%d, old: (%px len: %d), repl: (%px, len: %d), pad: %d",
a->cpuid >> 5,
a->cpuid & 0x1f,
instr, a->instrlen,
replacement, a->replacementlen, a->padlen);

- DUMP_BYTES(instr, a->instrlen, "%p: old_insn: ", instr);
- DUMP_BYTES(replacement, a->replacementlen, "%p: rpl_insn: ", replacement);
+ DUMP_BYTES(instr, a->instrlen, "%px: old_insn: ", instr);
+ DUMP_BYTES(replacement, a->replacementlen, "%px: rpl_insn: ", replacement);

memcpy(insnbuf, replacement, a->replacementlen);
insnbuf_sz = a->replacementlen;
@@ -433,7 +433,7 @@ void __init_or_module noinline apply_alternatives(struct alt_instr *start,
a->instrlen - a->replacementlen);
insnbuf_sz += a->instrlen - a->replacementlen;
}
- DUMP_BYTES(insnbuf, insnbuf_sz, "%p: final_insn: ", instr);
+ DUMP_BYTES(insnbuf, insnbuf_sz, "%px: final_insn: ", instr);

text_poke_early(instr, insnbuf, insnbuf_sz);
}
--
2.13.0