From a61b37ead51488e321fe559a4edd0325c6d4c937 Mon Sep 17 00:00:00 2001 From: Axel Lin Date: Mon, 21 Mar 2016 20:12:20 +0800 Subject: [PATCH 1/4] mailbox: xgene-slimpro: Fix wrong test for devm_kzalloc devm_kzalloc() returns NULL on failure. Signed-off-by: Axel Lin Signed-off-by: Jassi Brar --- drivers/mailbox/mailbox-xgene-slimpro.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/mailbox/mailbox-xgene-slimpro.c b/drivers/mailbox/mailbox-xgene-slimpro.c index bd07f39f0692..dd2afbca51c9 100644 --- a/drivers/mailbox/mailbox-xgene-slimpro.c +++ b/drivers/mailbox/mailbox-xgene-slimpro.c @@ -189,8 +189,8 @@ static int slimpro_mbox_probe(struct platform_device *pdev) int i; ctx = devm_kzalloc(&pdev->dev, sizeof(struct slimpro_mbox), GFP_KERNEL); - if (IS_ERR(ctx)) - return PTR_ERR(ctx); + if (!ctx) + return -ENOMEM; platform_set_drvdata(pdev, ctx); From 17f5f28ffa6e81461a569290ae802a9b05a89072 Mon Sep 17 00:00:00 2001 From: Lee Jones Date: Wed, 23 Mar 2016 14:43:41 +0000 Subject: [PATCH 2/4] mailbox: mailbox-test: Use more consistent format for calling copy_from_user() While we're at it, ensure copy-to location is NULL'ed in the error path. Suggested-by: Dan Carpenter Signed-off-by: Lee Jones Signed-off-by: Jassi Brar --- drivers/mailbox/mailbox-test.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/mailbox/mailbox-test.c b/drivers/mailbox/mailbox-test.c index dc11bbf27274..5f4b439fd45a 100644 --- a/drivers/mailbox/mailbox-test.c +++ b/drivers/mailbox/mailbox-test.c @@ -46,7 +46,6 @@ static ssize_t mbox_test_signal_write(struct file *filp, size_t count, loff_t *ppos) { struct mbox_test_device *tdev = filp->private_data; - int ret; if (!tdev->tx_channel) { dev_err(tdev->dev, "Channel cannot do Tx\n"); @@ -64,13 +63,13 @@ static ssize_t mbox_test_signal_write(struct file *filp, if (!tdev->signal) return -ENOMEM; - ret = copy_from_user(tdev->signal, userbuf, count); - if (ret) { + if (copy_from_user(tdev->signal, userbuf, count)) { kfree(tdev->signal); + tdev->signal = NULL; return -EFAULT; } - return ret < 0 ? ret : count; + return count; } static const struct file_operations mbox_test_signal_ops = { From d1c2f87c9a8f79fa8816bbe7de98da38eae2be5e Mon Sep 17 00:00:00 2001 From: Lee Jones Date: Wed, 23 Mar 2016 14:43:42 +0000 Subject: [PATCH 3/4] mailbox: mailbox-test: Prevent memory leak If we set the Signal twice or more, without using it as part of a message, memory will be re-allocated and the pointer over-written. Prevent this potential leak by only allocating memory when there isn't any already. Reported-by: Dan Carpenter Signed-off-by: Lee Jones Signed-off-by: Jassi Brar --- drivers/mailbox/mailbox-test.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/mailbox/mailbox-test.c b/drivers/mailbox/mailbox-test.c index 5f4b439fd45a..58d04726cdd7 100644 --- a/drivers/mailbox/mailbox-test.c +++ b/drivers/mailbox/mailbox-test.c @@ -59,9 +59,12 @@ static ssize_t mbox_test_signal_write(struct file *filp, return -EINVAL; } - tdev->signal = kzalloc(MBOX_MAX_SIG_LEN, GFP_KERNEL); - if (!tdev->signal) - return -ENOMEM; + /* Only allocate memory if we need to */ + if (!tdev->signal) { + tdev->signal = kzalloc(MBOX_MAX_SIG_LEN, GFP_KERNEL); + if (!tdev->signal) + return -ENOMEM; + } if (copy_from_user(tdev->signal, userbuf, count)) { kfree(tdev->signal); From 0c44d7896cbf9156b8bb10da4f665005622235ae Mon Sep 17 00:00:00 2001 From: Lee Jones Date: Wed, 23 Mar 2016 14:43:43 +0000 Subject: [PATCH 4/4] mailbox: Stop using ENOSYS for anything other than unimplemented syscalls In accordance with e15f431fe2d5 ("errno.h: Improve ENOSYS's comment") and 91c9afaf97ee ("checkpatch.pl: new instances of ENOSYS are errors") we're converting from the old meaning of: ENOSYS "Function not implemented" to a more standard EINVAL. Reported-by: Seraphin Bonnaffe Signed-off-by: Lee Jones Signed-off-by: Jassi Brar --- drivers/mailbox/mailbox.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c index 6a4811f85705..4a36632c236f 100644 --- a/drivers/mailbox/mailbox.c +++ b/drivers/mailbox/mailbox.c @@ -375,13 +375,13 @@ struct mbox_chan *mbox_request_channel_byname(struct mbox_client *cl, if (!np) { dev_err(cl->dev, "%s() currently only supports DT\n", __func__); - return ERR_PTR(-ENOSYS); + return ERR_PTR(-EINVAL); } if (!of_get_property(np, "mbox-names", NULL)) { dev_err(cl->dev, "%s() requires an \"mbox-names\" property\n", __func__); - return ERR_PTR(-ENOSYS); + return ERR_PTR(-EINVAL); } of_property_for_each_string(np, "mbox-names", prop, mbox_name) {