10:58 p.m.
The tty termios bits cannot change while n_tty_read() is in the
i/o loop; the termios_rwsem ensures mutual exclusion with termios
changes in n_tty_set_termios(). Check L_ICANON() directly and
eliminate icanon parameter.
NB: tty_audit_add_data() => tty_audit_buf_get() => tty_audit_buf_alloc()
is a single path; ie., tty_audit_buf_get() and tty_audit_buf_alloc()
have no other callers.
Signed-off-by: Peter Hurley <peter(a)hurleysoftware.com>
---
drivers/tty/n_tty.c | 6 +++---
drivers/tty/tty_audit.c | 22 +++++++++-------------
include/linux/tty.h | 4 ++--
3 files changed, 14 insertions(+), 18 deletions(-)
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index eeae6bc..5d060fc 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -162,7 +162,7 @@ static int tty_copy_to_user(struct tty_struct *tty, void __user *to,
int uncopied;
if (n > size) {
- tty_audit_add_data(tty, from, size, ldata->icanon);
+ tty_audit_add_data(tty, from, size);
uncopied = copy_to_user(to, from, size);
if (uncopied)
return uncopied;
@@ -171,7 +171,7 @@ static int tty_copy_to_user(struct tty_struct *tty, void __user *to,
from = ldata->read_buf;
}
- tty_audit_add_data(tty, from, n, ldata->icanon);
+ tty_audit_add_data(tty, from, n);
return copy_to_user(to, from, n);
}
@@ -1984,7 +1984,7 @@ static int copy_from_read_buf(struct tty_struct *tty,
retval = copy_to_user(*b, from, n);
n -= retval;
is_eof = n == 1 && *from == EOF_CHAR(tty);
- tty_audit_add_data(tty, from, n, ldata->icanon);
+ tty_audit_add_data(tty, from, n);
smp_store_release(&ldata->read_tail, ldata->read_tail + n);
/* Turn single EOF into zero-length read */
if (L_EXTPROC(tty) && ldata->icanon && is_eof &&
diff --git a/drivers/tty/tty_audit.c b/drivers/tty/tty_audit.c
index ead924e..d2a004a 100644
--- a/drivers/tty/tty_audit.c
+++ b/drivers/tty/tty_audit.c
@@ -22,8 +22,7 @@ struct tty_audit_buf {
unsigned char *data; /* Allocated size N_TTY_BUF_SIZE */
};
-static struct tty_audit_buf *tty_audit_buf_alloc(int major, int minor,
- unsigned icanon)
+static struct tty_audit_buf *tty_audit_buf_alloc(struct tty_struct *tty)
{
struct tty_audit_buf *buf;
@@ -35,9 +34,9 @@ static struct tty_audit_buf *tty_audit_buf_alloc(int major, int minor,
goto err_buf;
atomic_set(&buf->count, 1);
mutex_init(&buf->mutex);
- buf->major = major;
- buf->minor = minor;
- buf->icanon = icanon;
+ buf->major = tty->driver->major;
+ buf->minor = tty->driver->minor_start + tty->index;
+ buf->icanon = !!L_ICANON(tty);
buf->valid = 0;
return buf;
@@ -216,8 +215,7 @@ int tty_audit_push_current(void)
* if TTY auditing is disabled or out of memory. Otherwise, return a new
* reference to the buffer.
*/
-static struct tty_audit_buf *tty_audit_buf_get(struct tty_struct *tty,
- unsigned icanon)
+static struct tty_audit_buf *tty_audit_buf_get(struct tty_struct *tty)
{
struct tty_audit_buf *buf, *buf2;
unsigned long flags;
@@ -234,9 +232,7 @@ static struct tty_audit_buf *tty_audit_buf_get(struct tty_struct
*tty,
}
spin_unlock_irqrestore(¤t->sighand->siglock, flags);
- buf2 = tty_audit_buf_alloc(tty->driver->major,
- tty->driver->minor_start + tty->index,
- icanon);
+ buf2 = tty_audit_buf_alloc(tty);
if (buf2 == NULL) {
audit_log_lost("out of memory in TTY auditing");
return NULL;
@@ -265,13 +261,13 @@ static struct tty_audit_buf *tty_audit_buf_get(struct tty_struct
*tty,
*
* Audit @data of @size from @tty, if necessary.
*/
-void tty_audit_add_data(struct tty_struct *tty, const void *data,
- size_t size, unsigned icanon)
+void tty_audit_add_data(struct tty_struct *tty, const void *data, size_t size)
{
struct tty_audit_buf *buf;
int major, minor;
int audit_log_tty_passwd;
unsigned long flags;
+ unsigned int icanon = !!L_ICANON(tty);
if (unlikely(size == 0))
return;
@@ -286,7 +282,7 @@ void tty_audit_add_data(struct tty_struct *tty, const void *data,
if (!audit_log_tty_passwd && icanon && !L_ECHO(tty))
return;
- buf = tty_audit_buf_get(tty, icanon);
+ buf = tty_audit_buf_get(tty);
if (!buf)
return;
diff --git a/include/linux/tty.h b/include/linux/tty.h
index 56d1133..c1d1f08 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -604,7 +604,7 @@ extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
/* tty_audit.c */
#ifdef CONFIG_AUDIT
extern void tty_audit_add_data(struct tty_struct *tty, const void *data,
- size_t size, unsigned icanon);
+ size_t size);
extern void tty_audit_exit(void);
extern void tty_audit_fork(struct signal_struct *sig);
extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
@@ -612,7 +612,7 @@ extern void tty_audit_push(struct tty_struct *tty);
extern int tty_audit_push_current(void);
#else
static inline void tty_audit_add_data(struct tty_struct *tty, const void *data,
- size_t size, unsigned icanon)
+ size_t size)
{
}
static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
--
2.7.0