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e0b057b406
Commit f23571e8 "TOMOYO: Copy directly to userspace buffer." introduced tomoyo_flush() that flushes data to be read as soon as possible. tomoyo_select_domain() (which is called by write()) enqueues data which meant to be read by next read(), but previous read()'s read buffer's size was not cleared. As a result, since 2.6.36, sequence like char *cp = "select global-pid=1\n"; read(fd, buf1, sizeof(buf1)); write(fd, cp, strlen(cp)); read(fd, buf2, sizeof(buf2)); causes enqueued data to be flushed to buf1 rather than buf2. Fix this bug by clearing read buffer's size upon write() request. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>