The Wire ยท Showcase
BOOTCONFIG NULL POINTER FIX LANDS IN 7.2-RC1
By RepoJournal ยท Filed ยท About Linux
Kernel 7.2-rc1 merges a critical bootconfig patch that stops undefined pointer arithmetic from triggering UBSan and FORTIFY_SOURCE build failures.
The fix [1] addresses a real problem in xbc_snprint_cmdline() where the bootconfig subsystem was performing pointer arithmetic on NULL with size 0 during buffer length probing. This isn't a runtime crash waiting to happen - it's an undefined behavior catch that modern toolchains (UBSan, FORTIFY_SOURCE) were already flagging at build time. The patch reworks length tracking to use size_t instead, eliminating the undefined behavior without changing the actual logic. This lands early in the rc cycle, so expect it in stable by final release.
Action items
- โ Monitor 7.2-rc1 for any bootconfig-related regressions in your build pipeline torvalds/linux [monitor]
References
- [1] Merge tag 'bootconfig-fixes-v7.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace torvalds/linux
FAQ
- What changed in Linux on July 2, 2026?
- Kernel 7.2-rc1 merges a critical bootconfig patch that stops undefined pointer arithmetic from triggering UBSan and FORTIFY_SOURCE build failures.
- What should Linux teams do about it?
- Monitor 7.2-rc1 for any bootconfig-related regressions in your build pipeline
- Which Linux repositories shipped on July 2, 2026?
- torvalds/linux