CVE-2023-53550

In the Linux kernel, the following vulnerability has been resolved:

cpufreq: amd-pstate: fix global sysfs attribute type

In commit 3666062b87ec (cpufreq: amd-pstate: move to use bus_get_dev_root()) the amd_pstate attributes where moved from a dedicated kobject to the cpu root kobject.

While the dedicated kobject expects to contain kobj_attributes the root kobject needs device_attributes.

As the changed arguments are not used by the callbacks it works most of the time. However CFI will detect this issue:

[ 4947.849350] CFI failure at dev_attr_show+0x24/0x60 (target: show_status+0x0/0x70; expected type: 0x8651b1de) … [ 4947.849409] Call Trace: [ 4947.849410] [ 4947.849411] ? __warn+0xcf/0x1c0 [ 4947.849414] ? dev_attr_show+0x24/0x60 [ 4947.849415] ? report_cfi_failure+0x4e/0x60 [ 4947.849417] ? handle_cfi_failure+0x14c/0x1d0 [ 4947.849419] ? __cfi_show_status+0x10/0x10 [ 4947.849420] ? handle_bug+0x4f/0x90 [ 4947.849421] ? exc_invalid_op+0x1a/0x60 [ 4947.849422] ? asm_exc_invalid_op+0x1a/0x20 [ 4947.849424] ? __cfi_show_status+0x10/0x10 [ 4947.849425] ? dev_attr_show+0x24/0x60 [ 4947.849426] sysfs_kf_seq_show+0xa6/0x110 [ 4947.849433] seq_read_iter+0x16c/0x4b0 [ 4947.849436] vfs_read+0x272/0x2d0 [ 4947.849438] ksys_read+0x72/0xe0 [ 4947.849439] do_syscall_64+0x76/0xb0 [ 4947.849440] ? do_user_addr_fault+0x252/0x650 [ 4947.849442] ? exc_page_fault+0x7a/0x1b0 [ 4947.849443] entry_SYSCALL_64_after_hwframe+0x72/0xdc

Affected Software

References

• https://git.kernel.org/stable/c/5e720f8c8c9d959283c3908bbf32a91a01a86547
• https://git.kernel.org/stable/c/ddcfc33a20380508f7fea18e1c330abe17ed4fc0