From: Andrej Shadura <andrew.shadura@collabora.co.uk> stable inclusion from stable-5.10.71 commit a7f4c633ae120562e91a0891101ed44eaa6c6d1e bugzilla: 182981 https://gitee.com/openeuler/kernel/issues/I4I3KD Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 22d65765f211cc83186fd8b87521159f354c0da9 upstream. Since the actual_length calculation is performed unsigned, packets shorter than 7 bytes (e.g. packets without data or otherwise truncated) or non-received packets ("zero" bytes) can cause buffer overflow. Link: https://bugzilla.kernel.org/show_bug.cgi?id=214437 Fixes: 42337b9d4d958("HID: add driver for U2F Zero built-in LED and RNG") Signed-off-by: Andrej Shadura <andrew.shadura@collabora.co.uk> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- drivers/hid/hid-u2fzero.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/hid/hid-u2fzero.c b/drivers/hid/hid-u2fzero.c index 95e0807878c7..d70cd3d7f583 100644 --- a/drivers/hid/hid-u2fzero.c +++ b/drivers/hid/hid-u2fzero.c @@ -198,7 +198,9 @@ static int u2fzero_rng_read(struct hwrng *rng, void *data, } ret = u2fzero_recv(dev, &req, &resp); - if (ret < 0) + + /* ignore errors or packets without data */ + if (ret < offsetof(struct u2f_hid_msg, init.data)) return 0; /* only take the minimum amount of data it is safe to take */ -- 2.20.1