Patch "x86/alternative: Print unadorned pointers" has been added to the 4.15-stable tree

Patch "x86/alternative: Print unadorned pointers" has been added to the 4.15-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    x86/alternative: Print unadorned pointers

to the 4.15-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     x86alternative_Print_unadorned_pointers.patch
and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


Subject: x86/alternative: Print unadorned pointers
From: Borislav Petkov bp@suse.de
Date: Fri Jan 26 13:11:36 2018 +0100

From: Borislav Petkov bp@suse.de

commit 0e6c16c652cadaffd25a6bb326ec10da5bcec6b4

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@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: riel@redhat.com
Cc: ak@linux.intel.com
Cc: peterz@infradead.org
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: jikos@kernel.org
Cc: luto@amacapital.net
Cc: dave.hansen@intel.com
Cc: torvalds@linux-foundation.org
Cc: keescook@google.com
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: tim.c.chen@linux.intel.com
Cc: gregkh@linux-foundation.org
Cc: pjt@google.com
Link: https://lkml.kernel.org/r/20180126121139.31959-2-bp@alien8.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


---
 arch/x86/kernel/alternative.c |   14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -298,7 +298,7 @@ recompute_jump(struct alt_instr *a, u8 *
 	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 op
 	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_alt
 	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_alt
 			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_alt
 				 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);
 	}


Patches currently in stable-queue which might be from bp@suse.de are

queue-4.15/x86pti_Do_not_enable_PTI_on_CPUs_which_are_not_vulnerable_to_Meltdown.patch
queue-4.15/x86cpufeatures_Add_Intel_feature_bits_for_Speculation_Control.patch
queue-4.15/x86alternative_Print_unadorned_pointers.patch
queue-4.15/x86cpufeatures_Add_CPUID_7_EDX_CPUID_leaf.patch
queue-4.15/x86bugs_Drop_one_mitigation_from_dmesg.patch
queue-4.15/x86speculation_Simplify_indirect_branch_prediction_barrier().patch
queue-4.15/x86nospec_Fix_header_guards_names.patch
queue-4.15/x86retpoline_Simplify_vmexit_fill_RSB().patch
queue-4.15/x86cpufeatures_Clean_up_Spectre_v2_related_CPUID_flags.patch