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R. Silva" , Bill Wendling , Justin Stitt , linux-kernel@vger.kernel.org Subject: Re: [PATCH 30/82] s390/kexec_file: Refactor intentional wrap-around calculation In-Reply-To: (Alexander Gordeev's message of "Wed, 31 Jan 2024 15:22:01 +0100") References: <20240122235208.work.748-kees@kernel.org> <20240123002814.1396804-30-keescook@chromium.org> Date: Wed, 31 Jan 2024 15:40:31 +0100 Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Precedence: bulk X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain X-TM-AS-GCONF: 00 X-Proofpoint-GUID: hi5JB6CrT1YccCS8U5iW7QtK_X6slFsm X-Proofpoint-ORIG-GUID: ZPRMgtNbIfwvBkgv-v1cJY0vDW_eM9Fd X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.1011,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2024-01-31_08,2024-01-31_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 mlxlogscore=848 adultscore=0 impostorscore=0 suspectscore=0 priorityscore=1501 malwarescore=0 mlxscore=0 phishscore=0 spamscore=0 clxscore=1011 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311290000 definitions=main-2401310112 Alexander Gordeev writes: > On Mon, Jan 22, 2024 at 04:27:05PM -0800, Kees Cook wrote: >> diff --git a/arch/s390/kernel/machine_kexec_file.c b/arch/s390/kernel/machine_kexec_file.c >> index 8d207b82d9fe..e5e925423061 100644 >> --- a/arch/s390/kernel/machine_kexec_file.c >> +++ b/arch/s390/kernel/machine_kexec_file.c >> @@ -238,6 +238,7 @@ void *kexec_file_add_components(struct kimage *image, >> unsigned long max_command_line_size = LEGACY_COMMAND_LINE_SIZE; >> struct s390_load_data data = {0}; >> unsigned long minsize; >> + unsigned long sum; > > Please, use min_kernel_buf_len instead of sum. > > @Sven, could you please correct me if (minsize + max_command_line_size) > means something else. Your understanding is correct, minsize + max_command_line_size is the minimum required size of the kernel image.