diff options
author | Sasha Levin | 2021-02-05 22:50:32 -0500 |
---|---|---|
committer | Masahiro Yamada | 2021-02-16 12:01:45 +0900 |
commit | 9b82f13e7ef316cdc0a8858f1349f4defce3f9e0 (patch) | |
tree | ef2f3228421cb729a14a75950063009d95592f56 | |
parent | 98cd6f521f1016171e9e263effc7d6edfbf61da1 (diff) |
kbuild: clamp SUBLEVEL to 255
Right now if SUBLEVEL becomes larger than 255 it will overflow into the
territory of PATCHLEVEL, causing havoc in userspace that tests for
specific kernel version.
While userspace code tests for MAJOR and PATCHLEVEL, it doesn't test
SUBLEVEL at any point as ABI changes don't happen in the context of
stable tree.
Thus, to avoid overflows, simply clamp SUBLEVEL to it's maximum value in
the context of LINUX_VERSION_CODE. This does not affect "make
kernelversion" and such.
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
-rw-r--r-- | Makefile | 12 |
1 files changed, 9 insertions, 3 deletions
@@ -1247,9 +1247,15 @@ define filechk_utsrelease.h endef define filechk_version.h - echo \#define LINUX_VERSION_CODE $(shell \ - expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \ - echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))' + if [ $(SUBLEVEL) -gt 255 ]; then \ + echo \#define LINUX_VERSION_CODE $(shell \ + expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 255); \ + else \ + echo \#define LINUX_VERSION_CODE $(shell \ + expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \ + fi; \ + echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + \ + ((c) > 255 ? 255 : (c)))' endef $(version_h): FORCE |