]> git.ipfire.org Git - thirdparty/kernel/linux.git/commit
media: solo6x10: Check for out of bounds chip_id
authorKees Cook <kees@kernel.org>
Fri, 12 Dec 2025 03:00:35 +0000 (19:00 -0800)
committerHans Verkuil <hverkuil+cisco@kernel.org>
Tue, 13 Jan 2026 12:21:03 +0000 (13:21 +0100)
commit0fdf6323c35a134f206dcad5babb4ff488552076
tree69657657f0c151a4c541ae5250643ccc97fa1d02
parenta813338d910b49375018ebe960f912ca7672f88c
media: solo6x10: Check for out of bounds chip_id

Clang with CONFIG_UBSAN_SHIFT=y noticed a condition where a signed type
(literal "1" is an "int") could end up being shifted beyond 32 bits,
so instrumentation was added (and due to the double is_tw286x() call
seen via inlining), Clang decides the second one must now be undefined
behavior and elides the rest of the function[1]. This is a known problem
with Clang (that is still being worked on), but we can avoid the entire
problem by actually checking the existing max chip ID, and now there is
no runtime instrumentation added at all since everything is known to be
within bounds.

Additionally use an unsigned value for the shift to remove the
instrumentation even without the explicit bounds checking.

Link: https://github.com/ClangBuiltLinux/linux/issues/2144
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
[hverkuil: fix checkpatch warning for is_tw286x]
drivers/media/pci/solo6x10/solo6x10-tw28.c