CVE-2025-71139

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> kernel/kexec: fix IMA when allocation happens in CMA area<br /> <br /> *** Bug description ***<br /> <br /> When I tested kexec with the latest kernel, I ran into the following warning:<br /> <br /> [ 40.712410] ------------[ cut here ]------------<br /> [ 40.712576] WARNING: CPU: 2 PID: 1562 at kernel/kexec_core.c:1001 kimage_map_segment+0x144/0x198<br /> [...]<br /> [ 40.816047] Call trace:<br /> [ 40.818498] kimage_map_segment+0x144/0x198 (P)<br /> [ 40.823221] ima_kexec_post_load+0x58/0xc0<br /> [ 40.827246] __do_sys_kexec_file_load+0x29c/0x368<br /> [...]<br /> [ 40.855423] ---[ end trace 0000000000000000 ]---<br /> <br /> *** How to reproduce ***<br /> <br /> This bug is only triggered when the kexec target address is allocated in<br /> the CMA area. If no CMA area is reserved in the kernel, use the "cma="<br /> option in the kernel command line to reserve one.<br /> <br /> *** Root cause ***<br /> The commit 07d24902977e ("kexec: enable CMA based contiguous<br /> allocation") allocates the kexec target address directly on the CMA area<br /> to avoid copying during the jump. In this case, there is no IND_SOURCE<br /> for the kexec segment. But the current implementation of<br /> kimage_map_segment() assumes that IND_SOURCE pages exist and map them<br /> into a contiguous virtual address by vmap().<br /> <br /> *** Solution ***<br /> If IMA segment is allocated in the CMA area, use its page_address()<br /> directly.