{"id":12313,"date":"2026-09-04T18:54:16","date_gmt":"2026-09-04T10:54:16","guid":{"rendered":"https:\/\/www.54iter.cn\/?vuln=cve-2026-80633"},"modified":"2026-09-04T18:54:16","modified_gmt":"2026-09-04T10:54:16","slug":"cve-2026-80633","status":"publish","type":"vuln","link":"https:\/\/www.54iter.cn\/?vuln=cve-2026-80633","title":{"rendered":"CVE-2026-80633 [HIGH] &#8211; In the Linux kernel, the following vulnerability has been resolved:\n\niommufd: Take dma_res"},"content":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>iommufd: Take dma_resv lock before dma_buf_unpin() in release path<\/p>\n<p>dma_buf_unpin() requires the caller to hold the exporter&#8217;s dma_resv<br \/>\nlock:<\/p>\n<p>  void dma_buf_unpin(struct dma_buf_attachment *attach)<br \/>\n  {<br \/>\n          &#8230;<br \/>\n          dma_resv_assert_held(dmabuf-&gt;resv);<br \/>\n          &#8230;<br \/>\n  }<\/p>\n<p>iopt_release_pages() calls dma_buf_unpin() without taking that lock,<br \/>\nso every iommufd_ioas_destroy()\/iommufd_ioas_unmap() that releases<br \/>\nthe last reference on a DMABUF-backed iopt_pages triggers a WARN.<br \/>\nThis was hit while running tools\/testing\/selftests\/iommu\/iommufd:<\/p>\n<p>  WARNING: drivers\/dma-buf\/dma-buf.c:1137 at dma_buf_unpin+0x62\/0x70<br \/>\n  RIP: 0010:dma_buf_unpin+0x62\/0x70<br \/>\n  Call Trace:<\/p>\n<p>   dma_buf_unpin+0x62\/0x70<br \/>\n   iopt_release_pages+0xe4\/0x190<br \/>\n   iopt_unmap_iova_range+0x1c7\/0x290<br \/>\n   iopt_unmap_all+0x1a\/0x30<br \/>\n   iommufd_ioas_destroy+0x1d\/0x50<br \/>\n   iommufd_fops_release+0x93\/0x150<br \/>\n   __fput+0xfc\/0x2c0<br \/>\n   __x64_sys_close+0x3d\/0x80<br \/>\n   do_syscall_64+0x65\/0x180<\/p>\n<p>Take the dma_resv lock around dma_buf_unpin() in iopt_release_pages(),<br \/>\nmatching the iopt_map_dmabuf() convention. dma_buf_detach() acquires the<br \/>\nreservation lock internally, so it must remain outside the locked region.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>iommufd: Take dma_resv lock before dma_buf_unpin() in release path<\/p>\n<p>dma_buf_unpin() requires the caller to hold the exporter&#8217;s dma_<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-12313","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/12313","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=12313"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=12313"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=12313"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}