CC: [email protected] CC: [email protected] CC: [email protected] TO: Jing Zhang <[email protected]> CC: Paolo Bonzini <[email protected]> CC: David Matlack <[email protected]> CC: Ricardo Koller <[email protected]> CC: Krish Sadhukhan <[email protected]> CC: Fuad Tabba <[email protected]>
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 9a73fa375d58fee5262dd16473c8e7522bdf44de commit: cb082bfab59a224a49ae803fed52cd03e8d6b5e0 KVM: stats: Add fd-based API to read binary stats data date: 7 weeks ago :::::: branch date: 15 hours ago :::::: commit date: 7 weeks ago config: x86_64-randconfig-c001-20210806 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 42b9c2a17a0b63cccf3ac197a82f91b28e53e643) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=cb082bfab59a224a49ae803fed52cd03e8d6b5e0 git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout cb082bfab59a224a49ae803fed52cd03e8d6b5e0 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 clang-analyzer If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <[email protected]> clang-analyzer warnings: (new ones prefixed by >>) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/xen/grant-table.c:1360:2: note: Taking true branch if (xen_feature(XENFEAT_auto_translated_physmap)) { ^ drivers/xen/grant-table.c:1364:10: note: Assuming 'nr_gframes' is <= field 'count' BUG_ON(xen_auto_xlat_grant_frames.count < nr_gframes); ^ include/asm-generic/bug.h:63:45: note: expanded from macro 'BUG_ON' #define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0) ^~~~~~~~~ include/linux/compiler.h:78:42: note: expanded from macro 'unlikely' # define unlikely(x) __builtin_expect(!!(x), 0) ^ drivers/xen/grant-table.c:1364:3: note: Taking false branch BUG_ON(xen_auto_xlat_grant_frames.count < nr_gframes); ^ include/asm-generic/bug.h:63:32: note: expanded from macro 'BUG_ON' #define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0) ^ drivers/xen/grant-table.c:1364:3: note: Loop condition is false. Exiting loop BUG_ON(xen_auto_xlat_grant_frames.count < nr_gframes); ^ include/asm-generic/bug.h:63:27: note: expanded from macro 'BUG_ON' #define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0) ^ drivers/xen/grant-table.c:1374:9: note: Calling 'HYPERVISOR_memory_op' rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/x86/include/asm/xen/hypercall.h:334:9: note: Assigned value is garbage or undefined return _hypercall2(long, memory_op, cmd, arg); ^ arch/x86/include/asm/xen/hypercall.h:169:2: note: expanded from macro '_hypercall2' __HYPERCALL_DECLS; \ ^~~~~~~~~~~~~~~~~ arch/x86/include/asm/xen/hypercall.h:113:2: note: expanded from macro '__HYPERCALL_DECLS' register unsigned long __arg1 asm(__HYPERCALL_ARG1REG) = __arg1; \ ^ ~~~~~~ arch/x86/include/asm/xen/hypercall.h:382:9: warning: Assigned value is garbage or undefined [clang-analyzer-core.uninitialized.Assign] return _hypercall3(int, grant_table_op, cmd, uop, count); ^ arch/x86/include/asm/xen/hypercall.h:180:2: note: expanded from macro '_hypercall3' __HYPERCALL_DECLS; \ ^ arch/x86/include/asm/xen/hypercall.h:113:2: note: expanded from macro '__HYPERCALL_DECLS' register unsigned long __arg1 asm(__HYPERCALL_ARG1REG) = __arg1; \ ^ drivers/xen/grant-table.c:1479:19: note: Calling 'gnttab_max_grant_frames' max_nr_gframes = gnttab_max_grant_frames(); ^~~~~~~~~~~~~~~~~~~~~~~~~ drivers/xen/grant-table.c:716:25: note: Calling '__max_nr_grant_frames' unsigned int xen_max = __max_nr_grant_frames(); ^~~~~~~~~~~~~~~~~~~~~~~ drivers/xen/grant-table.c:707:7: note: Calling 'HYPERVISOR_grant_table_op' rc = HYPERVISOR_grant_table_op(GNTTABOP_query_size, &query, 1); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/x86/include/asm/xen/hypercall.h:382:9: note: Assigned value is garbage or undefined return _hypercall3(int, grant_table_op, cmd, uop, count); ^ arch/x86/include/asm/xen/hypercall.h:180:2: note: expanded from macro '_hypercall3' __HYPERCALL_DECLS; \ ^~~~~~~~~~~~~~~~~ arch/x86/include/asm/xen/hypercall.h:113:2: note: expanded from macro '__HYPERCALL_DECLS' register unsigned long __arg1 asm(__HYPERCALL_ARG1REG) = __arg1; \ ^ ~~~~~~ drivers/xen/grant-table.c:1363:3: warning: Value stored to 'rc' is never read [clang-analyzer-deadcode.DeadStores] rc = 0; ^ ~ drivers/xen/grant-table.c:1363:3: note: Value stored to 'rc' is never read rc = 0; ^ ~ Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 5 warnings generated. Suppressed 5 warnings (5 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 5 warnings generated. Suppressed 5 warnings (5 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 6 warnings generated. arch/x86/kvm/../../../virt/kvm/eventfd.c:385:2: warning: Value stored to 'ret' is never read [clang-analyzer-deadcode.DeadStores] ret = 0; ^ ~ arch/x86/kvm/../../../virt/kvm/eventfd.c:385:2: note: Value stored to 'ret' is never read ret = 0; ^ ~ Suppressed 5 warnings (5 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 5 warnings generated. Suppressed 5 warnings (5 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 5 warnings generated. Suppressed 5 warnings (5 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 6 warnings generated. Suppressed 6 warnings (5 in non-user code, 1 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 7 warnings generated. >> arch/x86/kvm/../../../virt/kvm/binary_stats.c:139:3: warning: Value stored >> to 'remain' is never read [clang-analyzer-deadcode.DeadStores] remain -= copylen; ^ ~~~~~~~ arch/x86/kvm/../../../virt/kvm/binary_stats.c:139:3: note: Value stored to 'remain' is never read remain -= copylen; ^ ~~~~~~~ >> arch/x86/kvm/../../../virt/kvm/binary_stats.c:141:3: warning: Value stored >> to 'dest' is never read [clang-analyzer-deadcode.DeadStores] dest += copylen; ^ ~~~~~~~ arch/x86/kvm/../../../virt/kvm/binary_stats.c:141:3: note: Value stored to 'dest' is never read dest += copylen; ^ ~~~~~~~ Suppressed 5 warnings (5 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 3 warnings generated. drivers/mfd/vx855.c:89:2: warning: Value stored to 'ret' is never read [clang-analyzer-deadcode.DeadStores] ret = mfd_add_devices(&pdev->dev, -1, vx855_cells, ARRAY_SIZE(vx855_cells), ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/mfd/vx855.c:89:2: note: Value stored to 'ret' is never read ret = mfd_add_devices(&pdev->dev, -1, vx855_cells, ARRAY_SIZE(vx855_cells), ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 3 warnings generated. kernel/trace/trace_printk.c:77:5: warning: Call to function 'strcpy' is insecure as it does not provide bounding of the memory buffer. Replace unbounded copy functions with analogous functions that support length arguments such as 'strlcpy'. CWE-119 [clang-analyzer-security.insecureAPI.strcpy] strcpy(fmt, *iter); ^~~~~~ kernel/trace/trace_printk.c:77:5: note: Call to function 'strcpy' is insecure as it does not provide bounding of the memory buffer. Replace unbounded copy functions with analogous functions that support length arguments such as 'strlcpy'. CWE-119 strcpy(fmt, *iter); ^~~~~~ Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (2 in non-user code, 2 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 3 warnings generated. drivers/acpi/acpica/rscreate.c:327:5: warning: Call to function 'strcpy' is insecure as it does not provide bounding of the memory buffer. Replace unbounded copy functions with analogous functions that support length arguments such as 'strlcpy'. CWE-119 [clang-analyzer-security.insecureAPI.strcpy] strcpy(user_prt->source, ^~~~~~ drivers/acpi/acpica/rscreate.c:327:5: note: Call to function 'strcpy' is insecure as it does not provide bounding of the memory buffer. Replace unbounded copy functions with analogous functions that support length arguments such as 'strlcpy'. CWE-119 strcpy(user_prt->source, ^~~~~~ Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. drivers/misc/eeprom/at24.c:334:2: warning: Value stored to 'client' is never read [clang-analyzer-deadcode.DeadStores] client = at24_client->client; ^ ~~~~~~~~~~~~~~~~~~~ drivers/misc/eeprom/at24.c:334:2: note: Value stored to 'client' is never read client = at24_client->client; ^ ~~~~~~~~~~~~~~~~~~~ drivers/misc/eeprom/at24.c:397:2: warning: Value stored to 'client' is never read [clang-analyzer-deadcode.DeadStores] client = at24_client->client; ^ ~~~~~~~~~~~~~~~~~~~ drivers/misc/eeprom/at24.c:397:2: note: Value stored to 'client' is never read client = at24_client->client; ^ ~~~~~~~~~~~~~~~~~~~ Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 6 warnings generated. drivers/misc/eeprom/idt_89hpesx.c:977:3: warning: Value stored to 'csraddr_len' is never read [clang-analyzer-deadcode.DeadStores] csraddr_len = strnlen(csraddr_str, count); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/misc/eeprom/idt_89hpesx.c:977:3: note: Value stored to 'csraddr_len' is never read csraddr_len = strnlen(csraddr_str, count); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~ Suppressed 5 warnings (2 in non-user code, 3 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. vim +/remain +139 arch/x86/kvm/../../../virt/kvm/binary_stats.c cb082bfab59a224 Jing Zhang 2021-06-18 12 cb082bfab59a224 Jing Zhang 2021-06-18 13 /** cb082bfab59a224 Jing Zhang 2021-06-18 14 * kvm_stats_read() - Common function to read from the binary statistics cb082bfab59a224 Jing Zhang 2021-06-18 15 * file descriptor. cb082bfab59a224 Jing Zhang 2021-06-18 16 * cb082bfab59a224 Jing Zhang 2021-06-18 17 * @id: identification string of the stats cb082bfab59a224 Jing Zhang 2021-06-18 18 * @header: stats header for a vm or a vcpu cb082bfab59a224 Jing Zhang 2021-06-18 19 * @desc: start address of an array of stats descriptors for a vm or a vcpu cb082bfab59a224 Jing Zhang 2021-06-18 20 * @stats: start address of stats data block for a vm or a vcpu cb082bfab59a224 Jing Zhang 2021-06-18 21 * @size_stats: the size of stats data block pointed by @stats cb082bfab59a224 Jing Zhang 2021-06-18 22 * @user_buffer: start address of userspace buffer cb082bfab59a224 Jing Zhang 2021-06-18 23 * @size: requested read size from userspace cb082bfab59a224 Jing Zhang 2021-06-18 24 * @offset: the start position from which the content will be read for the cb082bfab59a224 Jing Zhang 2021-06-18 25 * corresponding vm or vcp file descriptor cb082bfab59a224 Jing Zhang 2021-06-18 26 * cb082bfab59a224 Jing Zhang 2021-06-18 27 * The file content of a vm/vcpu file descriptor is now defined as below: cb082bfab59a224 Jing Zhang 2021-06-18 28 * +-------------+ cb082bfab59a224 Jing Zhang 2021-06-18 29 * | Header | cb082bfab59a224 Jing Zhang 2021-06-18 30 * +-------------+ cb082bfab59a224 Jing Zhang 2021-06-18 31 * | id string | cb082bfab59a224 Jing Zhang 2021-06-18 32 * +-------------+ cb082bfab59a224 Jing Zhang 2021-06-18 33 * | Descriptors | cb082bfab59a224 Jing Zhang 2021-06-18 34 * +-------------+ cb082bfab59a224 Jing Zhang 2021-06-18 35 * | Stats Data | cb082bfab59a224 Jing Zhang 2021-06-18 36 * +-------------+ cb082bfab59a224 Jing Zhang 2021-06-18 37 * Although this function allows userspace to read any amount of data (as long cb082bfab59a224 Jing Zhang 2021-06-18 38 * as in the limit) from any position, the typical usage would follow below cb082bfab59a224 Jing Zhang 2021-06-18 39 * steps: cb082bfab59a224 Jing Zhang 2021-06-18 40 * 1. Read header from offset 0. Get the offset of descriptors and stats data cb082bfab59a224 Jing Zhang 2021-06-18 41 * and some other necessary information. This is a one-time work for the cb082bfab59a224 Jing Zhang 2021-06-18 42 * lifecycle of the corresponding vm/vcpu stats fd. cb082bfab59a224 Jing Zhang 2021-06-18 43 * 2. Read id string from its offset. This is a one-time work for the lifecycle cb082bfab59a224 Jing Zhang 2021-06-18 44 * of the corresponding vm/vcpu stats fd. cb082bfab59a224 Jing Zhang 2021-06-18 45 * 3. Read descriptors from its offset and discover all the stats by parsing cb082bfab59a224 Jing Zhang 2021-06-18 46 * descriptors. This is a one-time work for the lifecycle of the cb082bfab59a224 Jing Zhang 2021-06-18 47 * corresponding vm/vcpu stats fd. cb082bfab59a224 Jing Zhang 2021-06-18 48 * 4. Periodically read stats data from its offset using pread. cb082bfab59a224 Jing Zhang 2021-06-18 49 * cb082bfab59a224 Jing Zhang 2021-06-18 50 * Return: the number of bytes that has been successfully read cb082bfab59a224 Jing Zhang 2021-06-18 51 */ cb082bfab59a224 Jing Zhang 2021-06-18 52 ssize_t kvm_stats_read(char *id, const struct kvm_stats_header *header, cb082bfab59a224 Jing Zhang 2021-06-18 53 const struct _kvm_stats_desc *desc, cb082bfab59a224 Jing Zhang 2021-06-18 54 void *stats, size_t size_stats, cb082bfab59a224 Jing Zhang 2021-06-18 55 char __user *user_buffer, size_t size, loff_t *offset) cb082bfab59a224 Jing Zhang 2021-06-18 56 { cb082bfab59a224 Jing Zhang 2021-06-18 57 ssize_t len; cb082bfab59a224 Jing Zhang 2021-06-18 58 ssize_t copylen; cb082bfab59a224 Jing Zhang 2021-06-18 59 ssize_t remain = size; cb082bfab59a224 Jing Zhang 2021-06-18 60 size_t size_desc; cb082bfab59a224 Jing Zhang 2021-06-18 61 size_t size_header; cb082bfab59a224 Jing Zhang 2021-06-18 62 void *src; cb082bfab59a224 Jing Zhang 2021-06-18 63 loff_t pos = *offset; cb082bfab59a224 Jing Zhang 2021-06-18 64 char __user *dest = user_buffer; cb082bfab59a224 Jing Zhang 2021-06-18 65 cb082bfab59a224 Jing Zhang 2021-06-18 66 size_header = sizeof(*header); cb082bfab59a224 Jing Zhang 2021-06-18 67 size_desc = header->num_desc * sizeof(*desc); cb082bfab59a224 Jing Zhang 2021-06-18 68 cb082bfab59a224 Jing Zhang 2021-06-18 69 len = KVM_STATS_NAME_SIZE + size_header + size_desc + size_stats - pos; cb082bfab59a224 Jing Zhang 2021-06-18 70 len = min(len, remain); cb082bfab59a224 Jing Zhang 2021-06-18 71 if (len <= 0) cb082bfab59a224 Jing Zhang 2021-06-18 72 return 0; cb082bfab59a224 Jing Zhang 2021-06-18 73 remain = len; cb082bfab59a224 Jing Zhang 2021-06-18 74 cb082bfab59a224 Jing Zhang 2021-06-18 75 /* cb082bfab59a224 Jing Zhang 2021-06-18 76 * Copy kvm stats header. cb082bfab59a224 Jing Zhang 2021-06-18 77 * The header is the first block of content userspace usually read out. cb082bfab59a224 Jing Zhang 2021-06-18 78 * The pos is 0 and the copylen and remain would be the size of header. cb082bfab59a224 Jing Zhang 2021-06-18 79 * The copy of the header would be skipped if offset is larger than the cb082bfab59a224 Jing Zhang 2021-06-18 80 * size of header. That usually happens when userspace reads stats cb082bfab59a224 Jing Zhang 2021-06-18 81 * descriptors and stats data. cb082bfab59a224 Jing Zhang 2021-06-18 82 */ cb082bfab59a224 Jing Zhang 2021-06-18 83 copylen = size_header - pos; cb082bfab59a224 Jing Zhang 2021-06-18 84 copylen = min(copylen, remain); cb082bfab59a224 Jing Zhang 2021-06-18 85 if (copylen > 0) { cb082bfab59a224 Jing Zhang 2021-06-18 86 src = (void *)header + pos; cb082bfab59a224 Jing Zhang 2021-06-18 87 if (copy_to_user(dest, src, copylen)) cb082bfab59a224 Jing Zhang 2021-06-18 88 return -EFAULT; cb082bfab59a224 Jing Zhang 2021-06-18 89 remain -= copylen; cb082bfab59a224 Jing Zhang 2021-06-18 90 pos += copylen; cb082bfab59a224 Jing Zhang 2021-06-18 91 dest += copylen; cb082bfab59a224 Jing Zhang 2021-06-18 92 } cb082bfab59a224 Jing Zhang 2021-06-18 93 cb082bfab59a224 Jing Zhang 2021-06-18 94 /* cb082bfab59a224 Jing Zhang 2021-06-18 95 * Copy kvm stats header id string. cb082bfab59a224 Jing Zhang 2021-06-18 96 * The id string is unique for every vm/vcpu, which is stored in kvm cb082bfab59a224 Jing Zhang 2021-06-18 97 * and kvm_vcpu structure. cb082bfab59a224 Jing Zhang 2021-06-18 98 * The id string is part of the stat header from the perspective of cb082bfab59a224 Jing Zhang 2021-06-18 99 * userspace, it is usually read out together with previous constant cb082bfab59a224 Jing Zhang 2021-06-18 100 * header part and could be skipped for later descriptors and stats cb082bfab59a224 Jing Zhang 2021-06-18 101 * data readings. cb082bfab59a224 Jing Zhang 2021-06-18 102 */ cb082bfab59a224 Jing Zhang 2021-06-18 103 copylen = header->id_offset + KVM_STATS_NAME_SIZE - pos; cb082bfab59a224 Jing Zhang 2021-06-18 104 copylen = min(copylen, remain); cb082bfab59a224 Jing Zhang 2021-06-18 105 if (copylen > 0) { cb082bfab59a224 Jing Zhang 2021-06-18 106 src = id + pos - header->id_offset; cb082bfab59a224 Jing Zhang 2021-06-18 107 if (copy_to_user(dest, src, copylen)) cb082bfab59a224 Jing Zhang 2021-06-18 108 return -EFAULT; cb082bfab59a224 Jing Zhang 2021-06-18 109 remain -= copylen; cb082bfab59a224 Jing Zhang 2021-06-18 110 pos += copylen; cb082bfab59a224 Jing Zhang 2021-06-18 111 dest += copylen; cb082bfab59a224 Jing Zhang 2021-06-18 112 } cb082bfab59a224 Jing Zhang 2021-06-18 113 cb082bfab59a224 Jing Zhang 2021-06-18 114 /* cb082bfab59a224 Jing Zhang 2021-06-18 115 * Copy kvm stats descriptors. cb082bfab59a224 Jing Zhang 2021-06-18 116 * The descriptors copy would be skipped in the typical case that cb082bfab59a224 Jing Zhang 2021-06-18 117 * userspace periodically read stats data, since the pos would be cb082bfab59a224 Jing Zhang 2021-06-18 118 * greater than the end address of descriptors cb082bfab59a224 Jing Zhang 2021-06-18 119 * (header->header.desc_offset + size_desc) causing copylen <= 0. cb082bfab59a224 Jing Zhang 2021-06-18 120 */ cb082bfab59a224 Jing Zhang 2021-06-18 121 copylen = header->desc_offset + size_desc - pos; cb082bfab59a224 Jing Zhang 2021-06-18 122 copylen = min(copylen, remain); cb082bfab59a224 Jing Zhang 2021-06-18 123 if (copylen > 0) { cb082bfab59a224 Jing Zhang 2021-06-18 124 src = (void *)desc + pos - header->desc_offset; cb082bfab59a224 Jing Zhang 2021-06-18 125 if (copy_to_user(dest, src, copylen)) cb082bfab59a224 Jing Zhang 2021-06-18 126 return -EFAULT; cb082bfab59a224 Jing Zhang 2021-06-18 127 remain -= copylen; cb082bfab59a224 Jing Zhang 2021-06-18 128 pos += copylen; cb082bfab59a224 Jing Zhang 2021-06-18 129 dest += copylen; cb082bfab59a224 Jing Zhang 2021-06-18 130 } cb082bfab59a224 Jing Zhang 2021-06-18 131 cb082bfab59a224 Jing Zhang 2021-06-18 132 /* Copy kvm stats values */ cb082bfab59a224 Jing Zhang 2021-06-18 133 copylen = header->data_offset + size_stats - pos; cb082bfab59a224 Jing Zhang 2021-06-18 134 copylen = min(copylen, remain); cb082bfab59a224 Jing Zhang 2021-06-18 135 if (copylen > 0) { cb082bfab59a224 Jing Zhang 2021-06-18 136 src = stats + pos - header->data_offset; cb082bfab59a224 Jing Zhang 2021-06-18 137 if (copy_to_user(dest, src, copylen)) cb082bfab59a224 Jing Zhang 2021-06-18 138 return -EFAULT; cb082bfab59a224 Jing Zhang 2021-06-18 @139 remain -= copylen; cb082bfab59a224 Jing Zhang 2021-06-18 140 pos += copylen; cb082bfab59a224 Jing Zhang 2021-06-18 @141 dest += copylen; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/[email protected]
.config.gz
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