mirrors
/
anolis-cloud-kernel
mirror of https://gitee.com/anolis/cloud-kernel.git
8
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

tty: Don't call panic() at tty_ldisc_init() 

syzbot is reporting kernel panic [1] triggered by memory allocation failure
at tty_ldisc_get() from tty_ldisc_init(). But since both tty_ldisc_get()
and caller of tty_ldisc_init() can cleanly handle errors, tty_ldisc_init()
does not need to call panic() when tty_ldisc_get() failed.

[1] https://syzkaller.appspot.com/bug?id=883431818e036ae6a9981156a64b821110f39187

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Tetsuo Handa 2018-04-05 19:40:16 +09:00 committed by Greg Kroah-Hartman
parent 598c2d41ff
commit 903f9db10f
3 changed files with 8 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
drivers/tty/tty_io.c
View File

@ -2816,7 +2816,10 @@ struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx)
kref_init(&tty->kref); kref_init(&tty->kref);
tty->magic = TTY_MAGIC; tty->magic = TTY_MAGIC;
tty_ldisc_init(tty); if (tty_ldisc_init(tty)) {
kfree(tty);
return NULL;
}
tty->session = NULL; tty->session = NULL;
tty->pgrp = NULL; tty->pgrp = NULL;
mutex_init(&tty->legacy_mutex); mutex_init(&tty->legacy_mutex);

5
drivers/tty/tty_ldisc.c
View File

@ -821,12 +821,13 @@ EXPORT_SYMBOL_GPL(tty_ldisc_release);
* the tty structure is not completely set up when this call is made. * the tty structure is not completely set up when this call is made.
*/ */
void tty_ldisc_init(struct tty_struct *tty) int tty_ldisc_init(struct tty_struct *tty)
{ {
struct tty_ldisc *ld = tty_ldisc_get(tty, N_TTY); struct tty_ldisc *ld = tty_ldisc_get(tty, N_TTY);
if (IS_ERR(ld)) if (IS_ERR(ld))
panic("n_tty: init_tty"); return PTR_ERR(ld);
tty->ldisc = ld; tty->ldisc = ld;
return 0;
} }
/** /**

2
include/linux/tty.h
View File

@ -701,7 +701,7 @@ extern int tty_unregister_ldisc(int disc);
extern int tty_set_ldisc(struct tty_struct *tty, int disc); extern int tty_set_ldisc(struct tty_struct *tty, int disc);
extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
extern void tty_ldisc_release(struct tty_struct *tty); extern void tty_ldisc_release(struct tty_struct *tty);
extern void tty_ldisc_init(struct tty_struct *tty); extern int __must_check tty_ldisc_init(struct tty_struct *tty);
extern void tty_ldisc_deinit(struct tty_struct *tty); extern void tty_ldisc_deinit(struct tty_struct *tty);
extern int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p, extern int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p,
char *f, int count); char *f, int count);