On 06. 07. 22, 7:44, D. Starke wrote:
From: Daniel Starke <daniel.starke@xxxxxxxxxxx>
gsmld_poll() currently fails to handle some corner cases correctly:
- tty ldisc association lost
- remote party closed the associated tty
Add the missing checks and map those to EPOLLHUP.
Reorder the checks to group them by their reaction.
Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Signed-off-by: Daniel Starke <daniel.starke@xxxxxxxxxxx>
---
drivers/tty/n_gsm.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
Based on tty-testing.
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 51447ccccbab..47566bd2ed6e 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -3051,14 +3051,20 @@ static __poll_t gsmld_poll(struct tty_struct *tty, struct file *file,
__poll_t mask = 0;
struct gsm_mux *gsm = tty->disc_data;
+ if (!gsm)
+ return EPOLLHUP;
Hmm, how can this happen? It's a tty bug if it calls ld ops after
NULLing disc_data.
thanks,
--
js
suse labs
