This pull request contains the following changes for UML:
- Make stub data pages configurable - Make it harder to mix user and kernel code by accident -----BEGIN PGP SIGNATURE----- iQJKBAABCAA0FiEEdgfidid8lnn52cLTZvlZhesYu8EFAmRSslcWHHJpY2hhcmRA c2lnbWEtc3Rhci5hdAAKCRBm+VmF6xi7wVbGEADWL/4rcVNqaD/b9V3bUXDkNhpG 81Jc9fXcx3OXV87GsxfadiQI05UaOhTAMWJlsdKUF0/IW5tSQSZc0QcDNxTs6aS1 NDkWvjk8s8OpbqdmV0cNKFmaeginrH4AuASajvNleU0BxX4ziqw6BPadih+wGVGz iVEd/M5YH2yet33pvD7Wzh3KZOPlo2OOKBqXzE6Snc3yoOiIfN95U8Cl23nxzMI4 F235LS5m+4+GWIMkYs6+hlWEa8SxSnsH/beQJxAybtetSHRxsDXOHlEpDI9olxYI +OFNqsFLDyhyjib2Snwt8HMES9VmMfUUwT7ZK1cChXN8Quix3lXAyz6rpocmdnL/ X1tzqWb1bz+yqrVRjtN3AGbcav+sQp4UWXsoExVsiz3lzaXfrbPvRZFucH2+SStK Wadyy2v2rHZKNq9sDLUBf5GJ0C4LrBAyT15ADim2L5/K7pZyI7AKSPcdU0Xc8m5y kMswml7FLaI+gsuKOBl7jySaoNDiVZFvQjsxd1+hn5cBNOcyBSt2rSErDw3geJgn pFzVkLtklfxMpHMm+bwXONBZMrXOBPNgo0gSkVrCVzO68x6j/MaBGLFazSqOKxbc UcVULhiomjIae4AcTomzOQx7oM1Xs3XuPo0x2RgJ3gMlCCZKoDNuqDgB3ZmPP/gq cbbHHveXEx7aMOPz0A== =Qb+I -----END PGP SIGNATURE----- Merge tag 'uml-for-linus-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux Pull uml updates from Richard Weinberger: - Make stub data pages configurable - Make it harder to mix user and kernel code by accident * tag 'uml-for-linus-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux: um: make stub data pages size tweakable um: prevent user code in modules um: further clean up user_syms um: don't export printf() um: hostfs: define our own API boundary um: add __weak for exported functions
This commit is contained in:
Linus Torvalds
Коммит
342528ff00
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@ -23,7 +23,8 @@
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#define STUB_START stub_start
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#define STUB_CODE STUB_START
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#define STUB_DATA (STUB_CODE + UM_KERN_PAGE_SIZE)
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#define STUB_END (STUB_DATA + UM_KERN_PAGE_SIZE)
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#define STUB_DATA_PAGES 1 /* must be a power of two */
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#define STUB_END (STUB_DATA + STUB_DATA_PAGES * UM_KERN_PAGE_SIZE)
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#ifndef __ASSEMBLY__
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@ -24,11 +24,12 @@
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void __attribute__ ((__section__ (".__syscall_stub")))
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stub_clone_handler(void)
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{
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struct stub_data *data = get_stub_page();
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struct stub_data *data = get_stub_data();
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long err;
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err = stub_syscall2(__NR_clone, CLONE_PARENT | CLONE_FILES | SIGCHLD,
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(unsigned long)data + UM_KERN_PAGE_SIZE / 2);
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(unsigned long)data +
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STUB_DATA_PAGES * UM_KERN_PAGE_SIZE / 2);
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if (err) {
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data->parent_err = err;
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goto done;
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@ -21,7 +21,7 @@ int init_new_context(struct task_struct *task, struct mm_struct *mm)
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unsigned long stack = 0;
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int ret = -ENOMEM;
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stack = get_zeroed_page(GFP_KERNEL);
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stack = __get_free_pages(GFP_KERNEL | __GFP_ZERO, ilog2(STUB_DATA_PAGES));
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if (stack == 0)
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goto out;
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@ -52,7 +52,7 @@ int init_new_context(struct task_struct *task, struct mm_struct *mm)
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out_free:
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if (to_mm->id.stack != 0)
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free_page(to_mm->id.stack);
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free_pages(to_mm->id.stack, ilog2(STUB_DATA_PAGES));
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out:
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return ret;
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}
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@ -74,6 +74,6 @@ void destroy_context(struct mm_struct *mm)
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}
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os_kill_ptraced_process(mmu->id.u.pid, 1);
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free_page(mmu->id.stack);
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free_pages(mmu->id.stack, ilog2(STUB_DATA_PAGES));
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free_ldt(mmu);
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}
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@ -326,9 +326,13 @@ int __init linux_main(int argc, char **argv)
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add_arg(DEFAULT_COMMAND_LINE_CONSOLE);
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host_task_size = os_get_top_address();
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/* reserve two pages for the stubs */
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host_task_size -= 2 * PAGE_SIZE;
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stub_start = host_task_size;
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/* reserve a few pages for the stubs (taking care of data alignment) */
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/* align the data portion */
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BUILD_BUG_ON(!is_power_of_2(STUB_DATA_PAGES));
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stub_start = (host_task_size - 1) & ~(STUB_DATA_PAGES * PAGE_SIZE - 1);
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/* another page for the code portion */
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stub_start -= PAGE_SIZE;
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host_task_size = stub_start;
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/*
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* TASK_SIZE needs to be PGDIR_SIZE aligned or else exit_mmap craps
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@ -262,7 +262,7 @@ static int userspace_tramp(void *stack)
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if (stack != NULL) {
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fd = phys_mapping(uml_to_phys(stack), &offset);
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addr = mmap((void *) STUB_DATA,
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UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE,
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STUB_DATA_PAGES * UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE,
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MAP_FIXED | MAP_SHARED, fd, offset);
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if (addr == MAP_FAILED) {
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printk(UM_KERN_ERR "mapping segfault stack at 0x%lx failed, errno = %d\n",
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@ -277,7 +277,7 @@ static int userspace_tramp(void *stack)
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(unsigned long) stub_segv_handler -
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(unsigned long) __syscall_stub_start;
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set_sigstack((void *) STUB_DATA, UM_KERN_PAGE_SIZE);
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set_sigstack((void *) STUB_DATA, STUB_DATA_PAGES * UM_KERN_PAGE_SIZE);
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sigemptyset(&sa.sa_mask);
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sa.sa_flags = SA_ONSTACK | SA_NODEFER | SA_SIGINFO;
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sa.sa_sigaction = (void *) v;
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@ -515,7 +515,7 @@ static int __init init_thread_regs(void)
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thread_regs[REGS_IP_INDEX] = STUB_CODE +
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(unsigned long) stub_clone_handler -
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(unsigned long) __syscall_stub_start;
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thread_regs[REGS_SP_INDEX] = STUB_DATA + UM_KERN_PAGE_SIZE -
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thread_regs[REGS_SP_INDEX] = STUB_DATA + STUB_DATA_PAGES * UM_KERN_PAGE_SIZE -
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sizeof(void *);
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#ifdef __SIGNAL_FRAMESIZE
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thread_regs[REGS_SP_INDEX] -= __SIGNAL_FRAMESIZE;
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@ -3,112 +3,40 @@
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#include <linux/types.h>
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#include <linux/module.h>
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/* Some of this are builtin function (some are not but could in the future),
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* so I *must* declare good prototypes for them and then EXPORT them.
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* The kernel code uses the macro defined by include/linux/string.h,
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* so I undef macros; the userspace code does not include that and I
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* add an EXPORT for the glibc one.
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/*
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* This file exports some critical string functions and compiler
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* built-in functions (where calls are emitted by the compiler
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* itself that we cannot avoid even in kernel code) to modules.
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*
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* "_user.c" code that previously used exports here such as hostfs
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* really should be considered part of the 'hypervisor' and define
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* its own API boundary like hostfs does now; don't add exports to
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* this file for such cases.
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*/
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#undef strlen
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#undef strstr
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#undef memcpy
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#undef memset
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extern size_t strlen(const char *);
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extern void *memmove(void *, const void *, size_t);
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extern void *memset(void *, int, size_t);
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extern int printf(const char *, ...);
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/* If it's not defined, the export is included in lib/string.c.*/
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#ifdef __HAVE_ARCH_STRSTR
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#undef strstr
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EXPORT_SYMBOL(strstr);
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#endif
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#ifndef __x86_64__
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#undef memcpy
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extern void *memcpy(void *, const void *, size_t);
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EXPORT_SYMBOL(memcpy);
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extern void *memmove(void *, const void *, size_t);
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EXPORT_SYMBOL(memmove);
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#undef memset
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extern void *memset(void *, int, size_t);
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EXPORT_SYMBOL(memset);
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#endif
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EXPORT_SYMBOL(printf);
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/* Here, instead, I can provide a fake prototype. Yes, someone cares: genksyms.
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* However, the modules will use the CRC defined *here*, no matter if it is
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* good; so the versions of these symbols will always match
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*/
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#define EXPORT_SYMBOL_PROTO(sym) \
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int sym(void); \
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EXPORT_SYMBOL(sym);
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extern void readdir64(void) __attribute__((weak));
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EXPORT_SYMBOL(readdir64);
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extern void truncate64(void) __attribute__((weak));
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EXPORT_SYMBOL(truncate64);
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#ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA
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/* needed for __access_ok() */
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EXPORT_SYMBOL(vsyscall_ehdr);
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EXPORT_SYMBOL(vsyscall_end);
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#endif
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EXPORT_SYMBOL_PROTO(__errno_location);
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EXPORT_SYMBOL_PROTO(access);
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EXPORT_SYMBOL_PROTO(open);
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EXPORT_SYMBOL_PROTO(open64);
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EXPORT_SYMBOL_PROTO(close);
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EXPORT_SYMBOL_PROTO(read);
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EXPORT_SYMBOL_PROTO(write);
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EXPORT_SYMBOL_PROTO(dup2);
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EXPORT_SYMBOL_PROTO(__xstat);
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EXPORT_SYMBOL_PROTO(__lxstat);
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EXPORT_SYMBOL_PROTO(__lxstat64);
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EXPORT_SYMBOL_PROTO(__fxstat64);
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EXPORT_SYMBOL_PROTO(lseek);
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EXPORT_SYMBOL_PROTO(lseek64);
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EXPORT_SYMBOL_PROTO(chown);
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EXPORT_SYMBOL_PROTO(fchown);
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EXPORT_SYMBOL_PROTO(truncate);
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EXPORT_SYMBOL_PROTO(ftruncate64);
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EXPORT_SYMBOL_PROTO(utime);
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EXPORT_SYMBOL_PROTO(utimes);
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EXPORT_SYMBOL_PROTO(futimes);
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EXPORT_SYMBOL_PROTO(chmod);
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EXPORT_SYMBOL_PROTO(fchmod);
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EXPORT_SYMBOL_PROTO(rename);
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EXPORT_SYMBOL_PROTO(__xmknod);
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EXPORT_SYMBOL_PROTO(symlink);
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EXPORT_SYMBOL_PROTO(link);
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EXPORT_SYMBOL_PROTO(unlink);
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EXPORT_SYMBOL_PROTO(readlink);
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EXPORT_SYMBOL_PROTO(mkdir);
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EXPORT_SYMBOL_PROTO(rmdir);
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EXPORT_SYMBOL_PROTO(opendir);
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EXPORT_SYMBOL_PROTO(readdir);
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EXPORT_SYMBOL_PROTO(closedir);
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EXPORT_SYMBOL_PROTO(seekdir);
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EXPORT_SYMBOL_PROTO(telldir);
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EXPORT_SYMBOL_PROTO(ioctl);
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EXPORT_SYMBOL_PROTO(pread64);
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EXPORT_SYMBOL_PROTO(pwrite64);
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EXPORT_SYMBOL_PROTO(statfs);
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EXPORT_SYMBOL_PROTO(statfs64);
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EXPORT_SYMBOL_PROTO(getuid);
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EXPORT_SYMBOL_PROTO(fsync);
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EXPORT_SYMBOL_PROTO(fdatasync);
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EXPORT_SYMBOL_PROTO(lstat64);
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EXPORT_SYMBOL_PROTO(fstat64);
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EXPORT_SYMBOL_PROTO(mknod);
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/* Export symbols used by GCC for the stack protector. */
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extern void __stack_smash_handler(void *) __attribute__((weak));
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EXPORT_SYMBOL(__stack_smash_handler);
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@ -117,6 +45,6 @@ extern long __guard __attribute__((weak));
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EXPORT_SYMBOL(__guard);
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#ifdef _FORTIFY_SOURCE
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extern int __sprintf_chk(char *str, int flag, size_t strlen, const char *format);
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extern int __sprintf_chk(char *str, int flag, size_t len, const char *format);
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EXPORT_SYMBOL(__sprintf_chk);
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#endif
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@ -4,8 +4,8 @@
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# ===========================================================================
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USER_SINGLE_OBJS := \
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$(foreach f,$(patsubst %.o,%,$(obj-y) $(obj-m)),$($(f)-objs))
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USER_OBJS += $(filter %_user.o,$(obj-y) $(obj-m) $(USER_SINGLE_OBJS))
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$(foreach f,$(patsubst %.o,%,$(obj-y)),$($(f)-objs))
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USER_OBJS += $(filter %_user.o,$(obj-y) $(USER_SINGLE_OBJS))
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USER_OBJS := $(foreach file,$(USER_OBJS),$(obj)/$(file))
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$(USER_OBJS:.o=.%): \
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@ -89,19 +89,19 @@ static inline void remap_stack_and_trap(void)
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"addl %4,%%ebx ; movl %%eax, (%%ebx) ;"
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"int $3"
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: :
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"g" (~(UM_KERN_PAGE_SIZE - 1)),
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"g" (~(STUB_DATA_PAGES * UM_KERN_PAGE_SIZE - 1)),
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"g" (STUB_MMAP_NR),
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"g" (UML_STUB_FIELD_FD),
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"g" (UML_STUB_FIELD_OFFSET),
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"g" (UML_STUB_FIELD_CHILD_ERR),
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"c" (UM_KERN_PAGE_SIZE),
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"c" (STUB_DATA_PAGES * UM_KERN_PAGE_SIZE),
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"d" (PROT_READ | PROT_WRITE),
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"S" (MAP_FIXED | MAP_SHARED)
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:
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"memory");
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}
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static __always_inline void *get_stub_page(void)
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static __always_inline void *get_stub_data(void)
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{
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unsigned long ret;
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@ -109,7 +109,7 @@ static __always_inline void *get_stub_page(void)
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"movl %%esp,%0 ;"
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"andl %1,%0"
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: "=a" (ret)
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: "g" (~(UM_KERN_PAGE_SIZE - 1)));
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: "g" (~(STUB_DATA_PAGES * UM_KERN_PAGE_SIZE - 1)));
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return (void *)ret;
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}
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|
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|
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@ -98,18 +98,18 @@ static inline void remap_stack_and_trap(void)
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"int3"
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: :
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"g" (STUB_MMAP_NR),
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"g" (~(UM_KERN_PAGE_SIZE - 1)),
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"g" (~(STUB_DATA_PAGES * UM_KERN_PAGE_SIZE - 1)),
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"g" (MAP_FIXED | MAP_SHARED),
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"g" (UML_STUB_FIELD_FD),
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"g" (UML_STUB_FIELD_OFFSET),
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"g" (UML_STUB_FIELD_CHILD_ERR),
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"S" (UM_KERN_PAGE_SIZE),
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"S" (STUB_DATA_PAGES * UM_KERN_PAGE_SIZE),
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"d" (PROT_READ | PROT_WRITE)
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:
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__syscall_clobber, "r10", "r8", "r9");
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}
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static __always_inline void *get_stub_page(void)
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static __always_inline void *get_stub_data(void)
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{
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unsigned long ret;
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@ -117,7 +117,7 @@ static __always_inline void *get_stub_page(void)
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"movq %%rsp,%0 ;"
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"andq %1,%0"
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: "=a" (ret)
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: "g" (~(UM_KERN_PAGE_SIZE - 1)));
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: "g" (~(STUB_DATA_PAGES * UM_KERN_PAGE_SIZE - 1)));
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return (void *)ret;
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}
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|
|
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|
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@ -11,7 +11,7 @@
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void __attribute__ ((__section__ (".__syscall_stub")))
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stub_segv_handler(int sig, siginfo_t *info, void *p)
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{
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struct faultinfo *f = get_stub_page();
|
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struct faultinfo *f = get_stub_data();
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ucontext_t *uc = p;
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|
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GET_FAULTINFO_FROM_MC(*f, &uc->uc_mcontext);
|
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|
|
|
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|
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@ -123,7 +123,7 @@ obj-$(CONFIG_9P_FS) += 9p/
|
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obj-$(CONFIG_AFS_FS) += afs/
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obj-$(CONFIG_NILFS2_FS) += nilfs2/
|
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obj-$(CONFIG_BEFS_FS) += befs/
|
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obj-$(CONFIG_HOSTFS) += hostfs/
|
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obj-y += hostfs/
|
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obj-$(CONFIG_CACHEFILES) += cachefiles/
|
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obj-$(CONFIG_DEBUG_FS) += debugfs/
|
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obj-$(CONFIG_TRACING) += tracefs/
|
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|
|
|
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|
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@ -3,9 +3,11 @@
|
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# Licensed under the GPL
|
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#
|
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|
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hostfs-objs := hostfs_kern.o hostfs_user.o
|
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hostfs-objs := hostfs_kern.o
|
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|
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obj-y :=
|
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hostfs-builtin-$(CONFIG_HOSTFS) += hostfs_user.o hostfs_user_exp.o
|
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|
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obj-y := $(hostfs-builtin-y) $(hostfs-builtin-m)
|
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obj-$(CONFIG_HOSTFS) += hostfs.o
|
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|
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include $(srctree)/arch/um/scripts/Makefile.rules
|
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|
|
|
|||
|
|
@ -0,0 +1,28 @@
|
|||
#include <linux/module.h>
|
||||
#include "hostfs.h"
|
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|
||||
EXPORT_SYMBOL_GPL(stat_file);
|
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EXPORT_SYMBOL_GPL(access_file);
|
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EXPORT_SYMBOL_GPL(open_file);
|
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EXPORT_SYMBOL_GPL(open_dir);
|
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EXPORT_SYMBOL_GPL(seek_dir);
|
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EXPORT_SYMBOL_GPL(read_dir);
|
||||
EXPORT_SYMBOL_GPL(read_file);
|
||||
EXPORT_SYMBOL_GPL(write_file);
|
||||
EXPORT_SYMBOL_GPL(lseek_file);
|
||||
EXPORT_SYMBOL_GPL(fsync_file);
|
||||
EXPORT_SYMBOL_GPL(replace_file);
|
||||
EXPORT_SYMBOL_GPL(close_file);
|
||||
EXPORT_SYMBOL_GPL(close_dir);
|
||||
EXPORT_SYMBOL_GPL(file_create);
|
||||
EXPORT_SYMBOL_GPL(set_attr);
|
||||
EXPORT_SYMBOL_GPL(make_symlink);
|
||||
EXPORT_SYMBOL_GPL(unlink_file);
|
||||
EXPORT_SYMBOL_GPL(do_mkdir);
|
||||
EXPORT_SYMBOL_GPL(hostfs_do_rmdir);
|
||||
EXPORT_SYMBOL_GPL(do_mknod);
|
||||
EXPORT_SYMBOL_GPL(link_file);
|
||||
EXPORT_SYMBOL_GPL(hostfs_do_readlink);
|
||||
EXPORT_SYMBOL_GPL(rename_file);
|
||||
EXPORT_SYMBOL_GPL(rename2_file);
|
||||
EXPORT_SYMBOL_GPL(do_statfs);
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