linux-kernel - [ 169/221] drm/nvc0/fb: fix crash when different mutex is used to protect same list

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

Message-Id: <20130115185010.240198388@linuxfoundation.org>
Date:	Tue, 15 Jan 2013 10:51:36 -0800
From:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	alan@...rguk.ukuu.org.uk, Aleksi Torhamo <aleksi@...hamo.net>,
	Roy Spliet <r.spliet@...dent.tudelft.nl>,
	Ben Skeggs <bskeggs@...hat.com>
Subject: [ 169/221] drm/nvc0/fb: fix crash when different mutex is used to protect same list

3.7-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Aleksi Torhamo <aleksi@...hamo.net>

commit 43f789792e2c7ea2bff37195e4c4b4239e9e02b7 upstream.

Fixes regression introduced in commit 861d2107
"drm/nouveau/fb: merge fb/vram and port to subdev interfaces"

nv50_fb_vram_{new,del} functions were changed to use
nouveau_subdev->mutex instead of the old nouveau_mm->mutex.
nvc0_fb_vram_new still uses the nouveau_mm->mutex, but nvc0 doesn't
have its own fb_vram_del function, using nv50_fb_vram_del instead.
Because of this, on nvc0 a different mutex ends up being used to protect
additions and deletions to the same list.

This patch is a -stable candidate for 3.7.

Signed-off-by: Aleksi Torhamo <aleksi@...hamo.net>
Reported-by: Roy Spliet <r.spliet@...dent.tudelft.nl>
Tested-by: Roy Spliet <r.spliet@...dent.tudelft.nl>
Signed-off-by: Ben Skeggs <bskeggs@...hat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 drivers/gpu/drm/nouveau/core/subdev/fb/nvc0.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/gpu/drm/nouveau/core/subdev/fb/nvc0.c
+++ b/drivers/gpu/drm/nouveau/core/subdev/fb/nvc0.c
@@ -86,14 +86,14 @@ nvc0_fb_vram_new(struct nouveau_fb *pfb,
 	mem->memtype = type;
 	mem->size = size;
 
-	mutex_lock(&mm->mutex);
+	mutex_lock(&pfb->base.mutex);
 	do {
 		if (back)
 			ret = nouveau_mm_tail(mm, 1, size, ncmin, align, &r);
 		else
 			ret = nouveau_mm_head(mm, 1, size, ncmin, align, &r);
 		if (ret) {
-			mutex_unlock(&mm->mutex);
+			mutex_unlock(&pfb->base.mutex);
 			pfb->ram.put(pfb, &mem);
 			return ret;
 		}
@@ -101,7 +101,7 @@ nvc0_fb_vram_new(struct nouveau_fb *pfb,
 		list_add_tail(&r->rl_entry, &mem->regions);
 		size -= r->length;
 	} while (size);
-	mutex_unlock(&mm->mutex);
+	mutex_unlock(&pfb->base.mutex);
 
 	r = list_first_entry(&mem->regions, struct nouveau_mm_node, rl_entry);
 	mem->offset = (u64)r->offset << 12;


--
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/