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| author | Sami Tolvanen <samitolvanen@google.com> | 2021-01-25 11:09:25 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-01-25 12:08:07 -0800 |
| commit | 9f12e37cae44a96132fc3031535a0b165486941a (patch) | |
| tree | d9cd1e0696432dde2a714f2abbe36685b2b78c72 | |
| parent | 007ad27d7bafc6df36e1d6ad4a13f6d602376193 (diff) | |
| download | linux-9f12e37cae44a96132fc3031535a0b165486941a.tar.bz2 | |
Commit 9bb48c82aced ("tty: implement write_iter") converted the tty
layer to use write_iter. Fix the redirected_tty_write declaration
also in n_tty and change the comparisons to use write_iter instead of
write.
[ Also moved the declaration of redirected_tty_write() to the proper
location in a header file. The reason for the bug was the bogus extern
declaration in n_tty.c silently not matching the changed definition in
tty_io.c, and because it wasn't in a shared header file, there was no
cross-checking of the declaration.
Sami noticed because Clang's Control Flow Integrity checking ended up
incidentally noticing the inconsistent declaration. - Linus ]
Fixes: 9bb48c82aced ("tty: implement write_iter")
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | drivers/tty/n_tty.c | 7 | ||||
| -rw-r--r-- | drivers/tty/tty_io.c | 2 | ||||
| -rw-r--r-- | include/linux/tty.h | 1 |
3 files changed, 3 insertions, 7 deletions
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c index 319d68c8a5df..219e85756171 100644 --- a/drivers/tty/n_tty.c +++ b/drivers/tty/n_tty.c @@ -2081,9 +2081,6 @@ static int canon_copy_from_read_buf(struct tty_struct *tty, return 0; } -extern ssize_t redirected_tty_write(struct file *, const char __user *, - size_t, loff_t *); - /** * job_control - check job control * @tty: tty @@ -2105,7 +2102,7 @@ static int job_control(struct tty_struct *tty, struct file *file) /* NOTE: not yet done after every sleep pending a thorough check of the logic of this change. -- jlc */ /* don't stop on /dev/console */ - if (file->f_op->write == redirected_tty_write) + if (file->f_op->write_iter == redirected_tty_write) return 0; return __tty_check_change(tty, SIGTTIN); @@ -2309,7 +2306,7 @@ static ssize_t n_tty_write(struct tty_struct *tty, struct file *file, ssize_t retval = 0; /* Job control check -- must be done at start (POSIX.1 7.1.1.4). */ - if (L_TOSTOP(tty) && file->f_op->write != redirected_tty_write) { + if (L_TOSTOP(tty) && file->f_op->write_iter != redirected_tty_write) { retval = tty_check_change(tty); if (retval) return retval; diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index 4a208a95e921..48de20916ca7 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -144,10 +144,8 @@ DEFINE_MUTEX(tty_mutex); static ssize_t tty_read(struct file *, char __user *, size_t, loff_t *); static ssize_t tty_write(struct kiocb *, struct iov_iter *); -ssize_t redirected_tty_write(struct kiocb *, struct iov_iter *); static __poll_t tty_poll(struct file *, poll_table *); static int tty_open(struct inode *, struct file *); -long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); #ifdef CONFIG_COMPAT static long tty_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg); diff --git a/include/linux/tty.h b/include/linux/tty.h index c873f475f0a7..37803f3e6d49 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -421,6 +421,7 @@ extern void tty_kclose(struct tty_struct *tty); extern int tty_dev_name_to_number(const char *name, dev_t *number); extern int tty_ldisc_lock(struct tty_struct *tty, unsigned long timeout); extern void tty_ldisc_unlock(struct tty_struct *tty); +extern ssize_t redirected_tty_write(struct kiocb *, struct iov_iter *); #else static inline void tty_kref_put(struct tty_struct *tty) { } |