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[37.24.206.209]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3997f99561dsm13322509f8f.12.2025.03.25.01.47.46 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 25 Mar 2025 01:47:47 -0700 (PDT) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: d3e2dea0-0955-11f0-9ea3-5ba50f476ded DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1742892467; x=1743497267; darn=lists.xenproject.org; h=content-transfer-encoding:autocrypt:content-language:cc:to:subject :from:user-agent:mime-version:date:message-id:from:to:cc:subject :date:message-id:reply-to; bh=Yg12JQpbt3xSZii10quMSUNM1Ae6R1UGjJH8iR4jZ4U=; b=bqOO504yx26u0VV21ta4brkjIYNO4UxjWEHdw3OWhfdy6sKVN7X2K4/EDjDESHUjy3 xhRDNk7dORfPaoDQjQkcWObd5oQRk+CquPst1AgAl6WgpMZBpYm2ysjJ2sxab+BkAb28 bsnrAhYQOnNG8kiiM9Vdx24RVP9K3gb9INHh8O++IsFiKofmkj2rPD1nGBbbjKmJZ7BP zefHxQ/BO8QgfQ7YkUZCOUAPtAxq/1kqoF7D8ZroUzw+M0+uQRgZO1YF4C4lTnDY70Ba IG3c+LEt5GcPr9piqIpQwnvO5vorvxlTHAO56/bgrOBez2tLdqzIp0o1KPEkWQrUMhet Y0bw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1742892467; x=1743497267; h=content-transfer-encoding:autocrypt:content-language:cc:to:subject :from:user-agent:mime-version:date:message-id:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=Yg12JQpbt3xSZii10quMSUNM1Ae6R1UGjJH8iR4jZ4U=; b=D+mnBGJ/E/IYCQW+ftNvVzvbfsXbVbgx8fHbhx26ciTATcgyS1L+aTWvLZTdyLXgOO MjLEC08RTAvOwHVYXA7Y2XmKsJ2XbeWNh3WmAToLxVfXk0QlELjFCGA1Sul/7Ao3SFSs gg/pvwUkw8FoC77IuezVCNEvglYhLokDK571cXAHWmgN/5/eE6cEd2K7QHg9WYePClOI EEFPpbobYjc0FvL8z+6BFXFKaeEtaPArMb2vorZtYPQugeCIyXFzuGDNcCrFKHh160oG PUOgtZI+m5++rRo6QTRq5oBNH5Gdl1DZawLTmZTYqzyryo70yyg8uRL5Q0T85AEP+j4X bMGg== X-Gm-Message-State: AOJu0Yx2ruohFH4Ah4cEC5+a6pceqJ1B8pz8HgFEHYCzDvlrEt8Vr02+ jtwUxSG0RVXzvDQf+AUqonf4uqg9DIJEESmG4PamN0A1mja+vDO8iILR5cw5ZsDfEH7nRLQbFcA = X-Gm-Gg: ASbGnctOsmRfo7k4gxnxKCLmXCkTqh0LvDsBvKBH1Bk+OIyDea/XkdSA0xpW18Ex0WJ jpUl40MpEmrbszPHE6K628tTX3wsFseRSBGhcs3tCt9NjasBLDgRSYxbYHuEripDnfI18CTlGyU zu3jjTxLyVWWvl28PQtM0nlfhXIIQmqqAbUAGs/cC0bxaIRPj/03o4UxlAdlcnh6h/opL1hxgtd 80Gs492mccorXzgEc7ZOhp5zHALCYlJDZYCvWaaHb9NuHe+KUkoEIWL6Nhccv6ApOnCItzbVYh8 kvlnB9T7JglllL3quYpacOF0v/Fz6mCP2dnbIX+jnZvbht8NWmjitS0cQc/skby3Z49a1EqHoMc 0q7jOaE/xWdqvTsR/lZ/p5D34ghD6Ow== X-Google-Smtp-Source: AGHT+IEE2txPys+XsdSX06hZvWGqolJ/3k2FKfSlRvhYsJYGeooOzR6LFfel7c8MJBNUvRiVTWmCVA== X-Received: by 2002:a05:6000:4014:b0:391:6fd:bb65 with SMTP id ffacd0b85a97d-3997f8f5e17mr15514201f8f.9.1742892467598; Tue, 25 Mar 2025 01:47:47 -0700 (PDT) Message-ID: <89d87fb0-88af-4495-92dd-cde28d8c25ff@suse.com> Date: Tue, 25 Mar 2025 09:47:46 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: Jan Beulich Subject: [PATCH v4] x86/PVH: account for module command line length To: "xen-devel@lists.xenproject.org" Cc: Andrew Cooper , =?utf-8?q?Roger_Pau_Monn?= =?utf-8?q?=C3=A9?= , Jason Andryuk Content-Language: en-US Autocrypt: addr=jbeulich@suse.com; keydata= xsDiBFk3nEQRBADAEaSw6zC/EJkiwGPXbWtPxl2xCdSoeepS07jW8UgcHNurfHvUzogEq5xk hu507c3BarVjyWCJOylMNR98Yd8VqD9UfmX0Hb8/BrA+Hl6/DB/eqGptrf4BSRwcZQM32aZK 7Pj2XbGWIUrZrd70x1eAP9QE3P79Y2oLrsCgbZJfEwCgvz9JjGmQqQkRiTVzlZVCJYcyGGsD /0tbFCzD2h20ahe8rC1gbb3K3qk+LpBtvjBu1RY9drYk0NymiGbJWZgab6t1jM7sk2vuf0Py O9Hf9XBmK0uE9IgMaiCpc32XV9oASz6UJebwkX+zF2jG5I1BfnO9g7KlotcA/v5ClMjgo6Gl MDY4HxoSRu3i1cqqSDtVlt+AOVBJBACrZcnHAUSuCXBPy0jOlBhxPqRWv6ND4c9PH1xjQ3NP nxJuMBS8rnNg22uyfAgmBKNLpLgAGVRMZGaGoJObGf72s6TeIqKJo/LtggAS9qAUiuKVnygo 3wjfkS9A3DRO+SpU7JqWdsveeIQyeyEJ/8PTowmSQLakF+3fote9ybzd880fSmFuIEJldWxp Y2ggPGpiZXVsaWNoQHN1c2UuY29tPsJgBBMRAgAgBQJZN5xEAhsDBgsJCAcDAgQVAggDBBYC AwECHgECF4AACgkQoDSui/t3IH4J+wCfQ5jHdEjCRHj23O/5ttg9r9OIruwAn3103WUITZee e7Sbg12UgcQ5lv7SzsFNBFk3nEQQCACCuTjCjFOUdi5Nm244F+78kLghRcin/awv+IrTcIWF hUpSs1Y91iQQ7KItirz5uwCPlwejSJDQJLIS+QtJHaXDXeV6NI0Uef1hP20+y8qydDiVkv6l IreXjTb7DvksRgJNvCkWtYnlS3mYvQ9NzS9PhyALWbXnH6sIJd2O9lKS1Mrfq+y0IXCP10eS FFGg+Av3IQeFatkJAyju0PPthyTqxSI4lZYuJVPknzgaeuJv/2NccrPvmeDg6Coe7ZIeQ8Yj t0ARxu2xytAkkLCel1Lz1WLmwLstV30g80nkgZf/wr+/BXJW/oIvRlonUkxv+IbBM3dX2OV8 AmRv1ySWPTP7AAMFB/9PQK/VtlNUJvg8GXj9ootzrteGfVZVVT4XBJkfwBcpC/XcPzldjv+3 HYudvpdNK3lLujXeA5fLOH+Z/G9WBc5pFVSMocI71I8bT8lIAzreg0WvkWg5V2WZsUMlnDL9 mpwIGFhlbM3gfDMs7MPMu8YQRFVdUvtSpaAs8OFfGQ0ia3LGZcjA6Ik2+xcqscEJzNH+qh8V m5jjp28yZgaqTaRbg3M/+MTbMpicpZuqF4rnB0AQD12/3BNWDR6bmh+EkYSMcEIpQmBM51qM EKYTQGybRCjpnKHGOxG0rfFY1085mBDZCH5Kx0cl0HVJuQKC+dV2ZY5AqjcKwAxpE75MLFkr wkkEGBECAAkFAlk3nEQCGwwACgkQoDSui/t3IH7nnwCfcJWUDUFKdCsBH/E5d+0ZnMQi+G0A nAuWpQkjM1ASeQwSHEeAWPgskBQL As per observation in practice, initrd->cmdline_pa is not normally zero. Hence so far we always appended at least one byte. That alone may already render insufficient the "allocation" made by find_memory(). Things would be worse when there's actually a (perhaps long) command line. Skip setup when the command line is empty. Amend the "allocation" size by padding and actual size of module command line. Along these lines also skip initrd setup when the initrd is zero size. Fixes: 0ecb8eb09f9f ("x86/pvh: pass module command line to dom0") Signed-off-by: Jan Beulich Reviewed-by: Jason Andryuk --- v4: Keep only ever accumulating into extra_space. v3: Permit empty initrd with non-empty module command line again. v2: Use elf_round_up(). Introduce initrd_cmdline local. Re-base. --- a/xen/arch/x86/hvm/dom0_build.c +++ b/xen/arch/x86/hvm/dom0_build.c @@ -652,6 +652,7 @@ static int __init pvh_load_kernel( unsigned long image_len = image->size; unsigned long initrd_len = initrd ? initrd->size : 0; const char *cmdline = image->cmdline_pa ? __va(image->cmdline_pa) : NULL; + const char *initrd_cmdline = NULL; struct elf_binary elf; struct elf_dom_parms parms; size_t extra_space; @@ -715,7 +716,23 @@ static int __init pvh_load_kernel( extra_space = sizeof(start_info); if ( initrd ) - extra_space += sizeof(mod) + ROUNDUP(initrd_len, PAGE_SIZE); + { + size_t initrd_space = elf_round_up(&elf, initrd_len); + + if ( initrd->cmdline_pa ) + { + initrd_cmdline = __va(initrd->cmdline_pa); + if ( !*initrd_cmdline ) + initrd_cmdline = NULL; + } + if ( initrd_cmdline ) + initrd_space += strlen(initrd_cmdline) + 1; + + if ( initrd_space ) + extra_space += ROUNDUP(initrd_space, PAGE_SIZE) + sizeof(mod); + else + initrd = NULL; + } if ( cmdline ) extra_space += elf_round_up(&elf, strlen(cmdline) + 1); @@ -740,12 +757,11 @@ static int __init pvh_load_kernel( mod.paddr = last_addr; mod.size = initrd_len; last_addr += elf_round_up(&elf, initrd_len); - if ( initrd->cmdline_pa ) + if ( initrd_cmdline ) { - char *str = __va(initrd->cmdline_pa); - size_t len = strlen(str) + 1; + size_t len = strlen(initrd_cmdline) + 1; - rc = hvm_copy_to_guest_phys(last_addr, str, len, v); + rc = hvm_copy_to_guest_phys(last_addr, initrd_cmdline, len, v); if ( rc ) { printk("Unable to copy module command line\n");