[PATCH AUTOSEL 4.14 50/60] mailbox: handle failed named mailbox channel request

From: Sasha Levin
Date: Fri Jul 19 2019 - 00:20:21 EST


From: morten petersen <morten_bp@xxxxxxx>

[ Upstream commit 25777e5784a7b417967460d4fcf9660d05a0c320 ]

Previously, if mbox_request_channel_byname was used with a name
which did not exist in the "mbox-names" property of a mailbox
client, the mailbox corresponding to the last entry in the
"mbox-names" list would be incorrectly selected.
With this patch, -EINVAL is returned if the named mailbox is
not found.

Signed-off-by: Morten Borup Petersen <morten_bp@xxxxxxx>
Signed-off-by: Jassi Brar <jaswinder.singh@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/mailbox/mailbox.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c
index 537f4f6d009b..44b49a2676f0 100644
--- a/drivers/mailbox/mailbox.c
+++ b/drivers/mailbox/mailbox.c
@@ -391,11 +391,13 @@ struct mbox_chan *mbox_request_channel_byname(struct mbox_client *cl,

of_property_for_each_string(np, "mbox-names", prop, mbox_name) {
if (!strncmp(name, mbox_name, strlen(name)))
- break;
+ return mbox_request_channel(cl, index);
index++;
}

- return mbox_request_channel(cl, index);
+ dev_err(cl->dev, "%s() could not locate channel named \"%s\"\n",
+ __func__, name);
+ return ERR_PTR(-EINVAL);
}
EXPORT_SYMBOL_GPL(mbox_request_channel_byname);

--
2.20.1