In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
fuse: Fix the condition to enable over-io-uring<\/p>\n
The existing condition in fuse_uring_cmd() is there only to avoid
\ndisabling io-uring for connections that already run with it, missing
\nwas a condition to refuse any IORING_OP_URING_CMD if the
\nconnection\/channel didn’t get enabled because of missing FUSE_INIT
\nreply flag FUSE_OVER_IO_URING. Without the reply flag the barrier in
\nfuse_uring_ready() doesn’t work and IO could already be going on and
\ncause deadlock states (at a minimum one between fch->bg_lock and
\nqueue->lock).<\/p>\n
The change itself is trivial, but brings behavior change,
\nFUSE_OVER_IO_URING has to be set in the FUSE_INIT_REPLY by fuse servers
\nto accept any IORING_OP_URING_CMD. Libfuse does that and the only
\nnon-libfuse implementation I found (fractal-fuse) also does it.
\nQemu patches for fuse-io-uring are not merged yet, as far as I know.<\/p>\n
Moved up is the smp_load_acquire(&fch->initialized) check, as a
\nfuse-server implementation might try to setup io-uring before FUSE_INIT
\nis processed and might have gotten -EOPNOTSUPP instead of -EAGAIN.<\/p>\n
Also fixed is a stale comment that explains the handling of the
\nFUSE_OVER_IO_URING flag in early RFC versions.<\/p>\n
If there should be a report from any library or application we
\nprobably need to revert this commit.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
fuse: Fix the condition to enable over-io-uring<\/p>\n
The existing condition in fuse_uring_cmd() is there only to avoid
\ndisabling io-uri<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-25504","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/25504","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=25504"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=25504"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=25504"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}