diff options
author | Nathan Chancellor <nathan@kernel.org> | 2024-05-29 14:29:42 -0700 |
---|---|---|
committer | Kees Cook <kees@kernel.org> | 2024-06-28 08:54:56 -0700 |
commit | 1c07c9be87dd3dd0634033bf08728b32465f08fb (patch) | |
tree | 2727e6d898ccc0bcc85599b8a2cd6804393bc6d9 | |
parent | 6db1208bf95b4c091897b597c415e11edeab2e2d (diff) |
tty: mxser: Remove __counted_by from mxser_board.ports[]
Work for __counted_by on generic pointers in structures (not just
flexible array members) has started landing in Clang 19 (current tip of
tree). During the development of this feature, a restriction was added
to __counted_by to prevent the flexible array member's element type from
including a flexible array member itself such as:
struct foo {
int count;
char buf[];
};
struct bar {
int count;
struct foo data[] __counted_by(count);
};
because the size of data cannot be calculated with the standard array
size formula:
sizeof(struct foo) * count
This restriction was downgraded to a warning but due to CONFIG_WERROR,
it can still break the build. The application of __counted_by on the
ports member of 'struct mxser_board' triggers this restriction,
resulting in:
drivers/tty/mxser.c:291:2: error: 'counted_by' should not be applied to an array with element of unknown size because 'struct mxser_port' is a struct type with a flexible array member. This will be an error in a future compiler version [-Werror,-Wbounds-safety-counted-by-elt-type-unknown-size]
291 | struct mxser_port ports[] __counted_by(nports);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.
Remove this use of __counted_by to fix the warning/error. However,
rather than remove it altogether, leave it commented, as it may be
possible to support this in future compiler releases.
Cc: <stable@vger.kernel.org>
Closes: https://github.com/ClangBuiltLinux/linux/issues/2026
Fixes: f34907ecca71 ("mxser: Annotate struct mxser_board with __counted_by")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20240529-drop-counted-by-ports-mxser-board-v1-1-0ab217f4da6d@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
-rw-r--r-- | drivers/tty/mxser.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c index 458bb1280ebf..5b97e420a95f 100644 --- a/drivers/tty/mxser.c +++ b/drivers/tty/mxser.c @@ -288,7 +288,7 @@ struct mxser_board { enum mxser_must_hwid must_hwid; speed_t max_baud; - struct mxser_port ports[] __counted_by(nports); + struct mxser_port ports[] /* __counted_by(nports) */; }; static DECLARE_BITMAP(mxser_boards, MXSER_BOARDS); |