lkml.org 
[lkml]   [2020]   [Jan]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.9 17/91] drm: limit to INT_MAX in create_blob ioctl
    Date
    From: Daniel Vetter <daniel.vetter@ffwll.ch>

    [ Upstream commit 5bf8bec3f4ce044a223c40cbce92590d938f0e9c ]

    The hardened usercpy code is too paranoid ever since commit 6a30afa8c1fb
    ("uaccess: disallow > INT_MAX copy sizes")

    Code itself should have been fine as-is.

    Link: http://lkml.kernel.org/r/20191106164755.31478-1-daniel.vetter@ffwll.ch
    Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
    Reported-by: syzbot+fb77e97ebf0612ee6914@syzkaller.appspotmail.com
    Fixes: 6a30afa8c1fb ("uaccess: disallow > INT_MAX copy sizes")
    Cc: Kees Cook <keescook@chromium.org>
    Cc: Alexander Viro <viro@zeniv.linux.org.uk>
    Cc: Stephen Rothwell <sfr@canb.auug.org.au>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
    Signed-off-by: Sasha Levin <sashal@kernel.org>
    ---
    drivers/gpu/drm/drm_property.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    diff --git a/drivers/gpu/drm/drm_property.c b/drivers/gpu/drm/drm_property.c
    index a4d81cf4ffa0..16c72d2ddc2e 100644
    --- a/drivers/gpu/drm/drm_property.c
    +++ b/drivers/gpu/drm/drm_property.c
    @@ -554,7 +554,7 @@ drm_property_create_blob(struct drm_device *dev, size_t length,
    struct drm_property_blob *blob;
    int ret;

    - if (!length || length > ULONG_MAX - sizeof(struct drm_property_blob))
    + if (!length || length > INT_MAX - sizeof(struct drm_property_blob))
    return ERR_PTR(-EINVAL);

    blob = kzalloc(sizeof(struct drm_property_blob)+length, GFP_KERNEL);
    --
    2.20.1


    \
     
     \ /
      Last update: 2020-01-11 11:01    [W:4.056 / U:1.812 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site