In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
drm\/imagination: acquire vm_ctx->lock before mapping memory to GPU VM<\/p>\n
The drm gpuvm code doesn’t protect find operation against map operation,
\nand the driver needs to ensure a map operation shouldn’t happen when a
\nfind operation is in progress.<\/p>\n
In some cases a find operation will be in progress when doing map\/unmap
\noperations, and the find operation will do a NULL pointer dereference.<\/p>\n
An example of the stack trace of such NULL dereference is shown below:<\/p>\n
“`
\nUnable to handle kernel access to user memory without uaccess routines at
\nvirtual address 0000000000000010<\/p>\n
[] drm_gpuva_find+0x28\/0x6c [drm_gpuvm]
\n[] pvr_vm_unmap+0x34\/0x68 [powervr]
\n[] pvr_ioctl_vm_unmap+0x2e\/0x50 [powervr]
\n[] drm_ioctl_kernel+0x8e\/0xdc
\n[] drm_ioctl+0x1be\/0x3e0
\n[] __riscv_sys_ioctl+0xba\/0xc4
\n[] do_trap_ecall_u+0x23e\/0x3f4
\n[] handle_exception+0x168\/0x174
\n“`<\/p>\n
As all occurences of drm_gpuva_find*() are already guarded by
\nvm_ctx->lock, make pvr_vm_map() to acquire this lock to prevent
\ndisturbing any find operation. This fixes the NULL deference problem in
\ndrm_gpuva_find*().<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
drm\/imagination: acquire vm_ctx->lock before mapping memory to GPU VM<\/p>\n
The drm gpuvm code doesn’t protect find operation against ma<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-5400","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/5400","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=5400"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=5400"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=5400"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}