All of lore.kernel.org
 help / color / mirror / Atom feed
From: Arnd Bergmann <arnd@arndb.de>
To: unlisted-recipients:; (no To-header on input)
Cc: Arnd Bergmann <arnd@arndb.de>,
	"Uladzislau Rezki (Sony)" <urezki@gmail.com>,
	Roman Gushchin <guro@fb.com>, Michal Hocko <mhocko@suse.com>,
	Matthew Wilcox <willy@infradead.org>,
	Thomas Garnier <thgarnie@google.com>,
	Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Joel Fernandes <joelaf@google.com>,
	Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
	Tejun Heo <tj@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Stephen Rothwell <sfr@canb.auug.org.au>,
	Roman Penyaev <rpenyaev@suse.de>,
	Rick Edgecombe <rick.p.edgecombe@intel.com>,
	Andrey Ryabinin <aryabinin@virtuozzo.com>,
	Mike Rapoport <rppt@linux.ibm.com>,
	linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: [BUG]: mm/vmalloc: uninitialized variable access in pcpu_get_vm_areas
Date: Mon, 17 Jun 2019 14:14:11 +0200	[thread overview]
Message-ID: <20190617121427.77565-1-arnd@arndb.de> (raw)

gcc points out some obviously broken code in linux-next

mm/vmalloc.c: In function 'pcpu_get_vm_areas':
mm/vmalloc.c:991:4: error: 'lva' may be used uninitialized in this function [-Werror=maybe-uninitialized]
    insert_vmap_area_augment(lva, &va->rb_node,
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     &free_vmap_area_root, &free_vmap_area_list);
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mm/vmalloc.c:916:20: note: 'lva' was declared here
  struct vmap_area *lva;
                    ^~~

Remove the obviously broken code. This is almost certainly
not the correct solution, but it's what I have applied locally
to get a clean build again.

Please fix this properly.

Fixes: 68ad4a330433 ("mm/vmalloc.c: keep track of free blocks for vmap allocation")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 mm/vmalloc.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index a9213fc3802d..bfcf0124a773 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -984,14 +984,9 @@ adjust_va_to_fit_type(struct vmap_area *va,
 		return -1;
 	}
 
-	if (type != FL_FIT_TYPE) {
+	if (type == FL_FIT_TYPE)
 		augment_tree_propagate_from(va);
 
-		if (type == NE_FIT_TYPE)
-			insert_vmap_area_augment(lva, &va->rb_node,
-				&free_vmap_area_root, &free_vmap_area_list);
-	}
-
 	return 0;
 }
 
-- 
2.20.0


WARNING: multiple messages have this Message-ID (diff)
From: Arnd Bergmann <arnd@arndb.de>
Cc: Arnd Bergmann <arnd@arndb.de>,
	"Uladzislau Rezki (Sony)" <urezki@gmail.com>,
	Roman Gushchin <guro@fb.com>, Michal Hocko <mhocko@suse.com>,
	Matthew Wilcox <willy@infradead.org>,
	Thomas Garnier <thgarnie@google.com>,
	Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Joel Fernandes <joelaf@google.com>,
	Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
	Tejun Heo <tj@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Stephen Rothwell <sfr@canb.auug.org.au>,
	Roman Penyaev <rpenyaev@suse.de>,
	Rick Edgecombe <rick.p.edgecombe@intel.com>,
	Andrey Ryabinin <aryabinin@virtuozzo.com>,
	Mike Rapoport <rppt@linux.ibm.com>,
	linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: [BUG]: mm/vmalloc: uninitialized variable access in pcpu_get_vm_areas
Date: Mon, 17 Jun 2019 14:14:11 +0200	[thread overview]
Message-ID: <20190617121427.77565-1-arnd@arndb.de> (raw)

gcc points out some obviously broken code in linux-next

mm/vmalloc.c: In function 'pcpu_get_vm_areas':
mm/vmalloc.c:991:4: error: 'lva' may be used uninitialized in this function [-Werror=maybe-uninitialized]
    insert_vmap_area_augment(lva, &va->rb_node,
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     &free_vmap_area_root, &free_vmap_area_list);
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mm/vmalloc.c:916:20: note: 'lva' was declared here
  struct vmap_area *lva;
                    ^~~

Remove the obviously broken code. This is almost certainly
not the correct solution, but it's what I have applied locally
to get a clean build again.

Please fix this properly.

Fixes: 68ad4a330433 ("mm/vmalloc.c: keep track of free blocks for vmap allocation")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 mm/vmalloc.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index a9213fc3802d..bfcf0124a773 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -984,14 +984,9 @@ adjust_va_to_fit_type(struct vmap_area *va,
 		return -1;
 	}
 
-	if (type != FL_FIT_TYPE) {
+	if (type == FL_FIT_TYPE)
 		augment_tree_propagate_from(va);
 
-		if (type == NE_FIT_TYPE)
-			insert_vmap_area_augment(lva, &va->rb_node,
-				&free_vmap_area_root, &free_vmap_area_list);
-	}
-
 	return 0;
 }
 
-- 
2.20.0


             reply	other threads:[~2019-06-17 12:16 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-06-17 12:14 Arnd Bergmann [this message]
2019-06-17 12:14 ` [BUG]: mm/vmalloc: uninitialized variable access in pcpu_get_vm_areas Arnd Bergmann
2019-06-17 13:49 ` Roman Penyaev
2019-06-17 14:04   ` Arnd Bergmann
2019-06-17 14:04     ` Arnd Bergmann
2019-06-17 14:40     ` Roman Penyaev
2019-06-17 14:12 ` Uladzislau Rezki
2019-06-17 14:44   ` Arnd Bergmann
2019-06-17 14:44     ` Arnd Bergmann
2019-06-17 14:50     ` Roman Penyaev
2019-06-17 14:50     ` Arnd Bergmann
2019-06-17 14:50       ` Arnd Bergmann
2019-06-17 16:57       ` Uladzislau Rezki
2019-06-17 19:29         ` Arnd Bergmann
2019-06-17 19:29           ` Arnd Bergmann
2019-06-18  8:01           ` Arnd Bergmann
2019-06-18  8:01             ` Arnd Bergmann
2019-06-18  8:53             ` Uladzislau Rezki

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190617121427.77565-1-arnd@arndb.de \
    --to=arnd@arndb.de \
    --cc=akpm@linux-foundation.org \
    --cc=aryabinin@virtuozzo.com \
    --cc=guro@fb.com \
    --cc=joelaf@google.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mhocko@suse.com \
    --cc=mingo@elte.hu \
    --cc=oleksiy.avramchenko@sonymobile.com \
    --cc=rick.p.edgecombe@intel.com \
    --cc=rostedt@goodmis.org \
    --cc=rpenyaev@suse.de \
    --cc=rppt@linux.ibm.com \
    --cc=sfr@canb.auug.org.au \
    --cc=tglx@linutronix.de \
    --cc=thgarnie@google.com \
    --cc=tj@kernel.org \
    --cc=torvalds@linux-foundation.org \
    --cc=urezki@gmail.com \
    --cc=willy@infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.