Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
of: check previous kernel’s ima-kexec-buffer against memory bounds
Presently ima_get_kexec_buffer() doesn’t check if the previous kernel’s ima-kexec-buffer lies outside the addressable memory range. This can result in a kernel panic if the new kernel is booted with ‘mem=X’ arg and the ima-kexec-buffer was allocated beyond that range by the previous kernel. The panic is usually of the form below:
$ sudo kexec –initrd initrd vmlinux –append=‘mem=16G’
Fix this issue by checking returned PFN range of previous kernel’s ima-kexec-buffer with page_is_ram() to ensure correct memory bounds.
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Oracle Linux 7 ELS , TuxCare 9.6 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- linux-hwe @ 4.15.0 (+8 more)
In the Linux kernel, the following vulnerability has been resolved:
of: check previous kernel’s ima-kexec-buffer against memory bounds
Presently ima_get_kexec_buffer() doesn’t check if the previous kernel’s ima-kexec-buffer lies outside the addressable memory range. This can result in a kernel panic if the new kernel is booted with ‘mem=X’ arg and the ima-kexec-buffer was allocated beyond that range by the previous kernel. The panic is usually of the form below:
$ sudo kexec –initrd initrd vmlinux –append=‘mem=16G’
Fix this issue by checking returned PFN range of previous kernel’s ima-kexec-buffer with page_is_ram() to ensure correct memory bounds.