zfsdev_getminor() should check for invalid file handles #3506
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Unit testing at ClusterHQ found that passing an invalid file handle to zfs_ioc_hold results in a NULL pointer dereference on a system without assertions: IP: [<ffffffffa0218aa0>] zfsdev_getminor+0x10/0x20 [zfs] Call Trace: [<ffffffffa021b4b0>] zfs_onexit_fd_hold+0x20/0x40 [zfs] [<ffffffffa0214043>] zfs_ioc_hold+0x93/0xd0 [zfs] [<ffffffffa0215890>] zfsdev_ioctl+0x200/0x500 [zfs] An assertion would have caught this had they been enabled, but this is something that the kernel module should handle without failing. We resolve this by searching the linked list to ensure that the file handle's private_data points to a valid zfsdev_state_t. Signed-off-by: Richard Yao <ryao@gentoo.org> Signed-off-by: Andriy Gapon <avg@FreeBSD.org> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
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Unit testing at ClusterHQ found that passing an invalid file handle to
zfs_ioc_hold results in a NULL pointer dereference on a system without
assertions:
IP: [] zfsdev_getminor+0x10/0x20 [zfs]
Call Trace:
[] zfs_onexit_fd_hold+0x20/0x40 [zfs]
[] zfs_ioc_hold+0x93/0xd0 [zfs]
[] zfsdev_ioctl+0x200/0x500 [zfs]
An assertion would have caught this had they been enabled, but this is
something that the kernel module should handle without failing. We
resolve this by searching the linked list to ensure that the file
handle's private_data points to a valid zfsdev_state_t.
Signed-off-by: Richard Yao ryao@gentoo.org
Signed-off-by: Andriy Gapon avg@FreeBSD.org
Signed-off-by: Brian Behlendorf behlendorf1@llnl.gov