linux-kernel - [PATCH] mm: trigger panic on bad page or PTE states if panic_on

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1426495021-6408-1-git-send-email-borntraeger@de.ibm.com>
Date:	Mon, 16 Mar 2015 09:37:01 +0100
From:	Christian Borntraeger <borntraeger@...ibm.com>
To:	linux-mm@...ck.org
Cc:	linux-kernel@...r.kernel.org,
	Christian Borntraeger <borntraeger@...ibm.com>
Subject: [PATCH] mm: trigger panic on bad page or PTE states if panic_on_oops

while debugging a memory management problem it helped a lot to
get a system dump as early as possible for bad page states.

Lets assume that if panic_on_oops is set then the system should
not continue with broken mm data structures.

Signed-off-by: Christian Borntraeger <borntraeger@...ibm.com>
---
 mm/memory.c     | 2 ++
 mm/page_alloc.c | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/mm/memory.c b/mm/memory.c
index 2c3536c..bdbf9cc 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -696,6 +696,8 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr,
 		printk(KERN_ALERT "vma->vm_file->f_op->mmap: %pSR\n",
 		       vma->vm_file->f_op->mmap);
 	dump_stack();
+	if (panic_on_oops)
+		panic("Fatal exception");
 	add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
 }
 
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 8e20f9c..8c19db3 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -337,6 +337,8 @@ static void bad_page(struct page *page, const char *reason,
 
 	print_modules();
 	dump_stack();
+	if (panic_on_oops)
+		panic("Fatal exception");
 out:
 	/* Leave bad fields for debug, except PageBuddy could make trouble */
 	page_mapcount_reset(page); /* remove PageBuddy */
-- 
2.3.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/