In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
platform\/x86: hp-bioscfg: fix heap OOB read in sk_store() and kek_store()<\/p>\n
sk_store() and kek_store() strip a trailing newline from the sysfs
\nwrite before allocating the key buffer:<\/p>\n
\tlength = count;
\n\tif (buf[length – 1] == ‘n’)
\n\t\tlength–;
\n\tbioscfg_drv.spm_data.signing_key = kmemdup(buf, length, GFP_KERNEL);<\/p>\n
but then pass the original “count” (not “length”) as the copy size to
\nhp_wmi_perform_query(), which memcpy()s that many bytes out of the
\n“length”-sized allocation, reading one byte past it whenever the write
\nends in a newline, the normal case for a shell “echo” into sysfs.<\/p>\n
KASAN confirms this directly:<\/p>\n
BUG: KASAN: slab-out-of-bounds in hp_wmi_perform_query+0x1e9\/0x460 [hp_bioscfg]
\n Read of size 28 at addr ffff88813c8e2b80 by task python3\/16022
\n …
\n sk_store+0xa7\/0x240 [hp_bioscfg]
\n kernfs_fop_write_iter+0x3e1\/0x5d0
\n …
\n The buggy address is located 0 bytes inside of
\n allocated 27-byte region [ffff88813c8e2b80, ffff88813c8e2b9b)<\/p>\n
Reproduced identically for kek_store, and at multiple write sizes
\n(28, 57, 201 bytes), each time reading exactly one byte past a
\nkmemdup() allocation one byte smaller than the write.<\/p>\n
Fix by passing “length” instead of “count” to hp_wmi_perform_query()
\nin both functions.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
platform\/x86: hp-bioscfg: fix heap OOB read in sk_store() and kek_store()<\/p>\n
sk_store() and kek_store() strip a trailing newline from<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-21347","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/21347","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=21347"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=21347"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=21347"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}