In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
bpf: Reject rdonly\/rdwr_buf_size kfunc arguments that exceed u32 max<\/p>\n
check_kfunc_args() detects a kfunc argument named rdonly_buf_size or
\nrdwr_buf_size and stores reg->var_off.value into meta->r0_size, a u64,
\nand does not bound it. check_kfunc_call() later copies that value into
\nthe returned register’s mem_size field:<\/p>\n
meta->r0_size = reg->var_off.value;
\n …
\n regs[BPF_REG_0].mem_size = meta.r0_size;<\/p>\n
regs[BPF_REG_0].mem_size is u32. A constant whose upper 32 bits are set
\ngets truncated instead of causing a load-time rejection, so the verifier
\nrecords a PTR_TO_MEM register with an approximately 4 GiB mem_size for
\nwhatever allocation the kfunc returned. A later access check against
\nthat register uses the truncated, wrong bound.<\/p>\n
Reject rdonly_buf_size\/rdwr_buf_size values that exceed U32_MAX at the
\npoint meta->r0_size is set.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
bpf: Reject rdonly\/rdwr_buf_size kfunc arguments that exceed u32 max<\/p>\n
check_kfunc_args() detects a kfunc argument named rdonly_buf_<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-25982","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/25982","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=25982"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=25982"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=25982"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}