Bugzilla – Bug 1222419
VUL-0: CVE-2024-26710: kernel: powerpc/kasan: Limit KASAN thread size increase to 32KB
Last modified: 2024-07-01 16:05:41 UTC
In the Linux kernel, the following vulnerability has been resolved: powerpc/kasan: Limit KASAN thread size increase to 32KB KASAN is seen to increase stack usage, to the point that it was reported to lead to stack overflow on some 32-bit machines (see link). To avoid overflows the stack size was doubled for KASAN builds in commit 3e8635fb2e07 ("powerpc/kasan: Force thread size increase with KASAN"). However with a 32KB stack size to begin with, the doubling leads to a 64KB stack, which causes build errors: arch/powerpc/kernel/switch.S:249: Error: operand out of range (0x000000000000fe50 is not between 0xffffffffffff8000 and 0x0000000000007fff) Although the asm could be reworked, in practice a 32KB stack seems sufficient even for KASAN builds - the additional usage seems to be in the 2-3KB range for a 64-bit KASAN build. So only increase the stack for KASAN if the stack size is < 32KB. References: http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2024-26710 https://www.cve.org/CVERecord?id=CVE-2024-26710 https://git.kernel.org/stable/c/4297217bcf1f0948a19c2bacc6b68d92e7778ad9 https://git.kernel.org/stable/c/4cc31fa07445879a13750cb061bb8c2654975fcb https://git.kernel.org/stable/c/b29b16bd836a838b7690f80e37f8376414c74cbe https://bugzilla.redhat.com/show_bug.cgi?id=2273162 https://git.kernel.org/stable/c/f1acb109505d983779bbb7e20a1ee6244d2b5736