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| author | Marc Kleine-Budde <mkl@pengutronix.de> | 2021-05-07 11:18:39 +0200 |
|---|---|---|
| committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2021-10-19 09:10:30 +0200 |
| commit | d674a8f123b4096d85955c7eaabec688f29724c9 (patch) | |
| tree | 32763e6e9e06edaa3a5fa538918b8cd40790613e | |
| parent | 8a64ef042eab8a6cec04a6c79d44d1af79b628ca (diff) | |
| download | lwn-d674a8f123b4096d85955c7eaabec688f29724c9.tar.gz lwn-d674a8f123b4096d85955c7eaabec688f29724c9.zip | |
can: isotp: isotp_sendmsg(): fix return error on FC timeout on TX path
When the a large chunk of data send and the receiver does not send a
Flow Control frame back in time, the sendmsg() does not return a error
code, but the number of bytes sent corresponding to the size of the
packet.
If a timeout occurs the isotp_tx_timer_handler() is fired, sets
sk->sk_err and calls the sk->sk_error_report() function. It was
wrongly expected that the error would be propagated to user space in
every case. For isotp_sendmsg() blocking on wait_event_interruptible()
this is not the case.
This patch fixes the problem by checking if sk->sk_err is set and
returning the error to user space.
Fixes: e057dd3fc20f ("can: add ISO 15765-2:2016 transport protocol")
Link: https://github.com/hartkopp/can-isotp/issues/42
Link: https://github.com/hartkopp/can-isotp/pull/43
Link: https://lore.kernel.org/all/20210507091839.1366379-1-mkl@pengutronix.de
Cc: stable@vger.kernel.org
Reported-by: Sottas Guillaume (LMB) <Guillaume.Sottas@liebherr.com>
Tested-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
| -rw-r--r-- | net/can/isotp.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/net/can/isotp.c b/net/can/isotp.c index d1f54273c0bb..df6968b28bf4 100644 --- a/net/can/isotp.c +++ b/net/can/isotp.c @@ -971,6 +971,9 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) if (wait_tx_done) { /* wait for complete transmission of current pdu */ wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE); + + if (sk->sk_err) + return -sk->sk_err; } return size; |