6.4-stable review patch. If anyone has any objections, please let me know.
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From: Rahul Rameshbabu sergeantsagara@protonmail.com
[ Upstream commit dd613a4e45f8d35f49a63a2064e5308fa5619e29 ]
Reference the HID device rather than the input device for the devm allocation of the input_dev name. Referencing the input_dev would lead to a use-after-free when the input_dev was unregistered and subsequently fires a uevent that depends on the name. At the point of firing the uevent, the name would be freed by devres management.
Use devm_kasprintf to simplify the logic for allocating memory and formatting the input_dev name string.
Reported-by: syzbot+3a0ebe8a52b89c63739d@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-input/ZOZIZCND+L0P1wJc@penguin/T/ Reported-by: Maxime Ripard mripard@kernel.org Closes: https://lore.kernel.org/linux-input/ZOZIZCND+L0P1wJc@penguin/T/#m443f3dce925... Fixes: cce2dbdf258e ("HID: uclogic: name the input nodes based on their tool") Suggested-by: Maxime Ripard mripard@kernel.org Suggested-by: Dmitry Torokhov dmitry.torokhov@gmail.com Signed-off-by: Rahul Rameshbabu sergeantsagara@protonmail.com Reviewed-by: Maxime Ripard mripard@kernel.org Link: https://lore.kernel.org/r/20230824061308.222021-2-sergeantsagara@protonmail.... Signed-off-by: Benjamin Tissoires bentiss@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/hid/hid-uclogic-core.c | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-)
diff --git a/drivers/hid/hid-uclogic-core.c b/drivers/hid/hid-uclogic-core.c index f67835f9ed4cc..ad74cbc9a0aa5 100644 --- a/drivers/hid/hid-uclogic-core.c +++ b/drivers/hid/hid-uclogic-core.c @@ -85,10 +85,8 @@ static int uclogic_input_configured(struct hid_device *hdev, { struct uclogic_drvdata *drvdata = hid_get_drvdata(hdev); struct uclogic_params *params = &drvdata->params; - char *name; const char *suffix = NULL; struct hid_field *field; - size_t len; size_t i; const struct uclogic_params_frame *frame;
@@ -146,14 +144,9 @@ static int uclogic_input_configured(struct hid_device *hdev, } }
- if (suffix) { - len = strlen(hdev->name) + 2 + strlen(suffix); - name = devm_kzalloc(&hi->input->dev, len, GFP_KERNEL); - if (name) { - snprintf(name, len, "%s %s", hdev->name, suffix); - hi->input->name = name; - } - } + if (suffix) + hi->input->name = devm_kasprintf(&hdev->dev, GFP_KERNEL, + "%s %s", hdev->name, suffix);
return 0; }