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Wed, 12 Feb 2025 14:03:00 +0100 Message-ID: <612ab8e6-a712-41f7-ae7f-7bdc0e3c1b90@web.de> Date: Wed, 12 Feb 2025 14:02:58 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: Wentao Liang , cgroups@vger.kernel.org, linux-block@vger.kernel.org Cc: stable@vger.kernel.org, LKML , Jens Axboe , Josef Bacik , Tejun Heo References: <20250212083203.1030-1-vulab@iscas.ac.cn> Subject: Re: [PATCH] block: Check blkg_to_lat() return value to avoid NULL dereference Content-Language: en-GB From: Markus Elfring In-Reply-To: <20250212083203.1030-1-vulab@iscas.ac.cn> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:oku5XT0L9VHT9UFRSvoG+4mbuVUZMifD03n2hUg0w+6+WPGrNAP Xc/Wbq87YEsS0LU84nPcZYuTW1WT9/t3F9NgZDbVsjz2Hwsd7atkKN5uqtzVK5NCLA+uhz4 leeRuhTgcsVWIPuZOkwFAWXYw+gZKn/7tKMn/HAyWOp6saYqAy3I+giefqXhK7N24gH18BU RFUNqC2ZNdf4CfkFZ25Gw== X-Spam-Flag: NO UI-OutboundReport: notjunk:1;M01:P0:Br8sEHTNNaU=;7Y7yedgzvBUlld/sjcV0dPcHaOM 7HNJxMyDRZFkPzc5REL5/tjhqNf4HJeBRJCC2DxMgC559YqNeoVtkRMfeBcP2GsAVtezymQ8q Hwe6fexjRkFzTQxoRbJAfcxNMBjOtGwrveenPm+wEJ/WONr5yqLRcjbF8i4OPOWzgJQ5PjgHA 3B8QNxe4sSjd0VeUdvWCRzwwEYWNOzOkA8RrQxOvE08wdGMMkx3ysd1uhjG3SJvIdkMj3NnFs +gRmLXv02iC5sO3KxXFaArPzxX5V+BTAb3lOEP8L1K5TMvXK+oMj3lFxdQ5x9Pv1AgUahE/3x /ki6YUC76RWPfJj3/f9IOrdPC5Hq2Rmg2nH8IQzkMr0Te0GmLDtfzOhxhe/rOKGPerGG/p6e5 /9d7Y6R1XtGs2M81vEvcU8qZjlB5Fvi10zQQsB69SUf2KX1fxT+rcvgvZHRMlzRcY83NXV1k4 rcnJfDPfSWmQY8reF15Y4MsWTRNnrLo/BQH/2M1FrRxw4deTIMVsM4fdUHP8eJploh7epLz9B J17DEVUTliDQNcpvCrSGYUYi3xhXUPxeXEKwKBvTtlEdhoDJy6P3FqwFM5RePsn5HbTbVXTmb s2SfytFSn+TAbtJ+RaUpgkMmvj5TrgkUtnQzSw63rk2JTvJsBQvcb0FyONX1CtdRhfjxap8lu NS+Y55WQuDnW4u6GulUC9NfU/iChLbbIXMkxnImXdyqK+wLN38N7GKPyDSGLimF8sS23+EBK/ 5mu614v9feRwrLSoCBpijCnTyoIYuIZCdFhIiYY3c0sKwPMiXl72Wvm70x4y2f3WUNOtBi3bc nmFT9RJNdnBxK7rQpvZSKrXLXkF6Klmwvl2ZQhhBvAd4WtQ6MG42Z/V3rDtOtolm9ZgvB7osu aYkRBRrO0jLkJA3i6ki9PcuKvtkUNc0tmE64mICv7MTYRdzPQJIDpB8beeCFq9A/H8k1lHBuk SMZFDsgl+GyMKOSQJql85YAoXBzl9rBm0t8+XVsEb6Srcpw8WJUsqQrSstrEvtUYR4go2bD49 0usK+I92gQUI1+RAY3Ca+fNOfv1vixylTYcSpwapi0qHx1mBqwzoTYmzKoEX0QVupOr/xS9q8 rOULITCLT5prF5a0ANHeWIiPRSIEFpSjYvB/vMlQ7nQR98xSZJ+s3EEQybycrQDMyLrK16t2u Ton7UNVbFbn3DRDl19BROFlYnx1EXpDOqdjdFDAfPJPCi/qas7f7T7fjhdhUq6z/EmalmyAAO v5M6QLELytl4UrGP04OebNUXXIrbHdJw+zbkHJeNQuKxkjvNv/GOWx9bx2UXLtMolPl4Fkenb dhGhAcRObIVhSfwoWw9TGrQcZjc1fnKV4lBVz2kOXO30eOvm+nGf3MfpT/WTTpxgh90iTQ01Y nxUcBLgxy9wLyGgDVW1evOvWcHogikcGFDGJxkYObAfFVayvxzBj6AlaDCC+HZTi/svDZNP87 FamWEQvOrlV04zSmdBtJg+lGRk1M= =E2=80=A6 > This patch adds checks for the return values of blkg_to_lat and let it See also: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Do= cumentation/process/submitting-patches.rst?h=3Dv6.14-rc2#n94 > returns early if it is NULL, preventing the NULL pointer dereference. return? Regards, Markus