Guanghui Feng 5cf604ee53 uio: Fix use-after-free in uio_open ... commit 0c9ae0b860 upstream. core-1 core-2 ------------------------------------------------------- uio_unregister_device uio_open idev = idr_find() device_unregister(&idev->dev) put_device(&idev->dev) uio_device_release get_device(&idev->dev) kfree(idev) uio_free_minor(minor) uio_release put_device(&idev->dev) kfree(idev) ------------------------------------------------------- In the core-1 uio_unregister_device(), the device_unregister will kfree idev when the idev->dev kobject ref is 1. But after core-1 device_unregister, put_device and before doing kfree, the core-2 may get_device. Then: 1. After core-1 kfree idev, the core-2 will do use-after-free for idev. 2. When core-2 do uio_release and put_device, the idev will be double freed. To address this issue, we can get idev atomic & inc idev reference with minor_lock. Fixes: 57c5f4df0a ("uio: fix crash after the device is unregistered") Cc: stable <stable@kernel.org> Signed-off-by: Guanghui Feng <guanghuifeng@linux.alibaba.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Link: https://lore.kernel.org/r/1703152663-59949-1-git-send-email-guanghuifeng@linux.alibaba.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2024-01-25 14:52:31 -08:00
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Kconfig
Makefile
uio_aec.c
uio_cif.c
uio_dfl.c
uio_dmem_genirq.c
uio_fsl_elbc_gpcm.c
uio_hv_generic.c
uio_mf624.c
uio_netx.c
uio_pci_generic.c
uio_pdrv_genirq.c
uio_pruss.c
uio_sercos3.c
uio.c	uio: Fix use-after-free in uio_open	2024-01-25 14:52:31 -08:00