linux-kernel - [PATCH AUTOSEL 4.19 087/167] drm/i915: Handle vm_mmap error during I915_GEM

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: <20190903162519.7136-87-sashal@kernel.org>
Date:   Tue,  3 Sep 2019 12:23:59 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Joonas Lahtinen <joonas.lahtinen@...ux.intel.com>,
        Adam Zabrocki <adamza@...rosoft.com>,
        Chris Wilson <chris@...is-wilson.co.uk>,
        Tvrtko Ursulin <tvrtko.ursulin@...ux.intel.com>,
        Tvrtko Ursulin <tvrtko.ursulin@...el.com>,
        Sasha Levin <sashal@...nel.org>,
        intel-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org
Subject: [PATCH AUTOSEL 4.19 087/167] drm/i915: Handle vm_mmap error during I915_GEM_MMAP ioctl with WC set

From: Joonas Lahtinen <joonas.lahtinen@...ux.intel.com>

[ Upstream commit ebfb6977801da521d8d5d752d373a187e2a2b9b3 ]

Add err goto label and use it when VMA can't be established or changes
underneath.

v2:
- Dropping Fixes: as it's indeed impossible to race an object to the
  error address. (Chris)
v3:
- Use IS_ERR_VALUE (Chris)

Reported-by: Adam Zabrocki <adamza@...rosoft.com>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@...ux.intel.com>
Cc: Chris Wilson <chris@...is-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@...ux.intel.com>
Cc: Adam Zabrocki <adamza@...rosoft.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@...el.com> #v2
Reviewed-by: Chris Wilson <chris@...is-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190207085454.10598-2-joonas.lahtinen@linux.intel.com
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/gpu/drm/i915/i915_gem.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index e81abd468a15d..9634d3adb8d01 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -1881,6 +1881,9 @@ i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
 	addr = vm_mmap(obj->base.filp, 0, args->size,
 		       PROT_READ | PROT_WRITE, MAP_SHARED,
 		       args->offset);
+	if (IS_ERR_VALUE(addr))
+		goto err;
+
 	if (args->flags & I915_MMAP_WC) {
 		struct mm_struct *mm = current->mm;
 		struct vm_area_struct *vma;
@@ -1896,17 +1899,22 @@ i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
 		else
 			addr = -ENOMEM;
 		up_write(&mm->mmap_sem);
+		if (IS_ERR_VALUE(addr))
+			goto err;
 
 		/* This may race, but that's ok, it only gets set */
 		WRITE_ONCE(obj->frontbuffer_ggtt_origin, ORIGIN_CPU);
 	}
 	i915_gem_object_put(obj);
-	if (IS_ERR((void *)addr))
-		return addr;
 
 	args->addr_ptr = (uint64_t) addr;
 
 	return 0;
+
+err:
+	i915_gem_object_put(obj);
+
+	return addr;
 }
 
 static unsigned int tile_row_pages(struct drm_i915_gem_object *obj)
-- 
2.20.1