On Mon 2014-07-21 08:02:36, Alex Elder wrote: > If a log record has LOG_PREFIX set, its predecessor record should be > terminated if it was marked LOG_CONT. > > In devkmsg_read(), this condition was being ignored, which would > lead to such records showing up combined when reading /dev/kmsg. > Fix this oversight. > > We should similarly insert a newline in msg_print_text() in this > case, to avoid formatted records getting merged. > > Suggested-by: Petr Mládek <[email protected]> > Signed-off-by: Alex Elder <[email protected]>
Reviewed-by: Petr Mladek <[email protected]> Best Regards, Petr > --- > kernel/printk/printk.c | 12 +++++++++++- > 1 file changed, 11 insertions(+), 1 deletion(-) > > diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c > index ffc9928..9f11eab 100644 > --- a/kernel/printk/printk.c > +++ b/kernel/printk/printk.c > @@ -575,6 +575,7 @@ static ssize_t devkmsg_read(struct file *file, char > __user *buf, > char cont = '-'; > size_t len; > ssize_t ret; > + bool insert_newline; > > if (!user) > return -EBADF; > @@ -625,7 +626,10 @@ static ssize_t devkmsg_read(struct file *file, char > __user *buf, > ((user->prev & LOG_CONT) && !(msg->flags & LOG_PREFIX))) > cont = '+'; > > - len = sprintf(user->buf, "%u,%llu,%llu,%c;", > + /* Insert a newline if the previous line was not terminated properly */ > + insert_newline = (user->prev & LOG_CONT) && (msg->flags & LOG_PREFIX); > + len = sprintf(user->buf, "%s%u,%llu,%llu,%c;", > + insert_newline ? "\n" : "", > (msg->facility << 3) | msg->level, > user->seq, ts_usec, cont); > user->prev = msg->flags; > @@ -1013,6 +1017,12 @@ static size_t msg_print_text(const struct printk_log > *msg, enum log_flags prev, > newline = false; > } > > + if ((prev & LOG_CONT) && (msg->flags & LOG_PREFIX) && len < size) { > + if (buf) > + buf[len++] = '\n'; > + else > + len++; > + } > do { > const char *next = memchr(text, '\n', text_size); > size_t text_len; > -- > 1.9.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
