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55ee64b30a
Walking rbtree while it's modified is a Bad Idea(tm); besides, the result of find_vma() can be freed just as it's getting returned to caller. Fortunately, it's easy to fix - just take ->mmap_sem a bit earlier (and don't bother with find_vma() at all if virtp >= PAGE_OFFSET - in that case we don't even look at its result). While we are at it, what prevents VIDIOC_PREPARE_BUF calling v4l_prepare_buf() -> (e.g) vb2_ioctl_prepare_buf() -> vb2_prepare_buf() -> __buf_prepare() -> __qbuf_userptr() -> vb2_vmalloc_get_userptr() -> find_vma(), AFAICS without having taken ->mmap_sem anywhere in process? The code flow is bloody convoluted and depends on a bunch of things done by initialization, so I certainly might've missed something... Cc: stable@vger.kernel.org [2.6.35] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Sakari Ailus <sakari.ailus@iki.fi> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Cc: Archit Taneja <archit@ti.com> Cc: Prabhakar Lad <prabhakar.lad@ti.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com> |
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| .. | ||
| common | ||
| dvb-core | ||
| dvb-frontends | ||
| firewire | ||
| i2c | ||
| mmc | ||
| parport | ||
| pci | ||
| platform | ||
| radio | ||
| rc | ||
| tuners | ||
| usb | ||
| v4l2-core | ||
| Kconfig | ||
| Makefile | ||
| media-device.c | ||
| media-devnode.c | ||
| media-entity.c | ||