In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
parport: Fix race between port and client registration<\/p>\n
The parport subsystem registers port devices before they are fully
\ninitialised, resulting in a race condition where client drivers such
\nas lp can attach to ports that are not completely initialised or even
\nbeing torn down.<\/p>\n
When the port and client drivers are built as modules and loaded
\naround the same time during boot, this occasionally results in a
\ncrash. I was able to make this happen reliably in a VM with a
\nPC-style parallel port by patching parport_pc to fail probing:<\/p>\n
> — a\/drivers\/parport\/parport_pc.c
\n> +++ b\/drivers\/parport\/parport_pc.c
\n> @@ -2069,7 +2069,7 @@ static struct parport *__parport_pc_probe_port(unsigned long int base,
\n> \tif (!p)
\n> \t\tgoto out3;
\n>
\n> –\tbase_res = request_region(base, 3, p->name);
\n> +\tbase_res = NULL;
\n> \tif (!base_res)
\n> \t\tgoto out4;
\n><\/p>\n
and then running:<\/p>\n
while true; do
\n modprobe lp & modprobe parport_pc
\n\twait
\n\trmmod lp parport_pc
\n done<\/p>\n
for a few seconds.<\/p>\n
In the long term I think port registration should be changed to put
\nthe call to device_add() inside parport_announce_port(), but since the
\nlatter currently cannot fail this will require changing all port
\ndrivers.<\/p>\n
For now, add a flag to indicate whether a port has been “announced”
\nand only try to attach client drivers to ports when the flag is set.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
parport: Fix race between port and client registration<\/p>\n
The parport subsystem registers port devices before they are fully
\ninitiali<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-14972","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/14972","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=14972"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=14972"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=14972"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}