1

mm: ptdump: add check_wx_pages debugfs attribute

Add a readable attribute in debugfs to trigger a W^X pages check at any
time.

To trigger the test, just read /sys/kernel/debug/check_wx_pages It will
report FAILED if the test failed, SUCCESS otherwise.

Detailed result is provided into dmesg.

Link: https://lkml.kernel.org/r/e947fb1a9f3f5466344823e532d343ff194ae03d.1706610398.git.christophe.leroy@csgroup.eu
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@kernel.org>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Greg KH <greg@kroah.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Phong Tran <tranmanphong@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Steven Price <steven.price@arm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Christophe Leroy 2024-01-30 11:34:36 +01:00 committed by Andrew Morton
parent 6cdc82db0c
commit 565474afe0

View File

@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0 // SPDX-License-Identifier: GPL-2.0
#include <linux/pagewalk.h> #include <linux/pagewalk.h>
#include <linux/debugfs.h>
#include <linux/ptdump.h> #include <linux/ptdump.h>
#include <linux/kasan.h> #include <linux/kasan.h>
@ -163,3 +164,24 @@ void ptdump_walk_pgd(struct ptdump_state *st, struct mm_struct *mm, pgd_t *pgd)
/* Flush out the last page */ /* Flush out the last page */
st->note_page(st, 0, -1, 0); st->note_page(st, 0, -1, 0);
} }
static int check_wx_show(struct seq_file *m, void *v)
{
if (ptdump_check_wx())
seq_puts(m, "SUCCESS\n");
else
seq_puts(m, "FAILED\n");
return 0;
}
DEFINE_SHOW_ATTRIBUTE(check_wx);
static int ptdump_debugfs_init(void)
{
debugfs_create_file("check_wx_pages", 0400, NULL, NULL, &check_wx_fops);
return 0;
}
device_initcall(ptdump_debugfs_init);