net: phy: fix phy_get_internal_delay accessing an empty array

stable inclusion
from stable-v5.10.214
commit 06dd21045a7e8bc8701b0ebedcd9a30a6325878b
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9L9N4

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=06dd21045a7e8bc8701b0ebedcd9a30a6325878b



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[ Upstream commit 4469c0c5b14a0919f5965c7ceac96b523eb57b79 ]

The phy_get_internal_delay function could try to access to an empty
array in the case that the driver is calling phy_get_internal_delay
without defining delay_values and rx-internal-delay-ps or
tx-internal-delay-ps is defined to 0 in the device-tree.
This will lead to "unable to handle kernel NULL pointer dereference at
virtual address 0". To avoid this kernel oops, the test should be delay
>= 0. As there is already delay < 0 test just before, the test could
only be size == 0.

Fixes: 92252eec ("net: phy: Add a helper to return the index for of the internal delay")
Co-developed-by: Enguerrand de Ribaucourt <enguerrand.de-ribaucourt@savoirfairelinux.com>
Signed-off-by: Enguerrand de Ribaucourt <enguerrand.de-ribaucourt@savoirfairelinux.com>
Signed-off-by: Kévin L'hôpital <kevin.lhopital@savoirfairelinux.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Wang Hai <wanghai38@huawei.com>