vfs: O_* bit numbers uniqueness check (454eedb8) · Commits · 戴 / test

The O_* bit numbers are defined in 20+ arch/*, and can silently overlap. Add a compile time check to ensure the uniqueness as suggested by David Miller. Signed-off-by:

Wu Fengguang <fengguang.wu@intel.com> Cc: David Miller <davem@davemloft.net> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: Eric Paris <eparis@redhat.com> Cc: Roland Dreier <rdreier@cisco.com> Cc: Jamie Lokier <jamie@shareable.org> Cc: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

fs/fcntl.c

+13 −2

Original line number	Diff line number	Diff line
		@@ -767,11 +767,22 @@ void kill_fasync(struct fasync_struct **fp, int sig, int band)
		}
		EXPORT_SYMBOL(kill_fasync);

		static int __init fasync_init(void)
		static int __init fcntl_init(void)
		{
		/* please add new bits here to ensure allocation uniqueness */
		BUILD_BUG_ON(19 - 1 /* for O_RDONLY being 0 */ != HWEIGHT32(
		O_RDONLY \| O_WRONLY \| O_RDWR \|
		O_CREAT \| O_EXCL \| O_NOCTTY \|
		O_TRUNC \| O_APPEND \| O_NONBLOCK \|
		__O_SYNC \| O_DSYNC \| FASYNC \|
		O_DIRECT \| O_LARGEFILE \| O_DIRECTORY \|
		O_NOFOLLOW \| O_NOATIME \| O_CLOEXEC \|
		FMODE_EXEC
		));

		fasync_cache = kmem_cache_create("fasync_cache",
		sizeof(struct fasync_struct), 0, SLAB_PANIC, NULL);
		return 0;
		}

		module_init(fasync_init)
		module_init(fcntl_init)

include/asm-generic/fcntl.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -11,6 +11,10 @@
		* -Eric Paris
		*/

		/*
		* When introducing new O_* bits, please check its uniqueness in fcntl_init().
		*/

		#define O_ACCMODE 00000003
		#define O_RDONLY 00000000
		#define O_WRONLY 00000001

Admin message