// SPDX-License-Identifier: GPL-2.0/****************************************************************************//* * linux/fs/binfmt_flat.c * * Copyright (C) 2000-2003 David McCullough <davidm@snapgear.com> * Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com> * Copyright (C) 2002 SnapGear, by Paul Dale <pauli@snapgear.com> * Copyright (C) 2000, 2001 Lineo, by David McCullough <davidm@lineo.com> * based heavily on: * * linux/fs/binfmt_aout.c: * Copyright (C) 1991, 1992, 1996 Linus Torvalds * linux/fs/binfmt_flat.c for 2.0 kernel * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com> * JAN/99 -- coded full program relocation (gerg@snapgear.com) */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/kernel.h>#include <linux/sched.h>#include <linux/sched/task_stack.h>#include <linux/mm.h>#include <linux/mman.h>#include <linux/errno.h>#include <linux/signal.h>#include <linux/string.h>#include <linux/fs.h>#include <linux/file.h>#include <linux/ptrace.h>#include <linux/user.h>#include <linux/slab.h>#include <linux/binfmts.h>#include <linux/personality.h>#include <linux/init.h>#include <linux/flat.h>#include <linux/uaccess.h>#include <linux/vmalloc.h> #include <asm/byteorder.h>#include <linux/unaligned.h>#include <asm/cacheflush.h>#include <asm/page.h>#include <asm/flat.h> #ifndef flat_get_relocate_addr#define flat_get_relocate_addr(rel) (rel)#endif /****************************************************************************/ /* * User data (data section and bss) needs to be aligned. * We pick 0x20 here because it is the max value elf2flt has always * used in producing FLAT files, and because it seems to be large * enough to make all the gcc alignment related tests happy. */#define FLAT_DATA_ALIGN (0x20) /* * User data (stack) also needs to be aligned. * Here we can be a bit looser than the data sections since this * needs to only meet arch ABI requirements. */#define FLAT_STACK_ALIGN max_t(unsigned long, sizeof(void *), ARCH_SLAB_MINALIGN) #define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */#define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */ #define MAX_SHARED_LIBS (1) #ifdef CONFIG_BINFMT_FLAT_NO_DATA_START_OFFSET#define DATA_START_OFFSET_WORDS (0)#define MAX_SHARED_LIBS_UPDATE (0)#else#define DATA_START_OFFSET_WORDS (MAX_SHARED_LIBS)#define MAX_SHARED_LIBS_UPDATE (MAX_SHARED_LIBS)#endif struct lib_info { struct { unsigned long start_code; /* Start of text segment */ unsigned long start_data; /* Start of data segment */ unsigned long start_brk; /* End of data segment */ unsigned long text_len; /* Length of text segment */ unsigned long entry; /* Start address for this module */ unsigned long build_date; /* When this one was compiled */ bool loaded; /* Has this library been loaded? */ } lib_list[MAX_SHARED_LIBS];}; static int load_flat_binary(struct linux_binprm *); static struct linux_binfmt flat_format = { .module = THIS_MODULE, .load_binary = load_flat_binary,}; /****************************************************************************//* * create_flat_tables() parses the env- and arg-strings in new user * memory and creates the pointer tables from them, and puts their * addresses on the "stack", recording the new stack pointer value. */ static int create_flat_tables(struct linux_binprm *bprm, unsigned long arg_start){ char __user *p; unsigned long __user *sp; long i, len; p = (char __user *)arg_start; sp = (unsigned long __user *)current->mm->start_stack; sp -= bprm->envc + 1; sp -= bprm->argc + 1; if (IS_ENABLED(CONFIG_BINFMT_FLAT_ARGVP_ENVP_ON_STACK)) sp -= 2; /* argvp + envp */ sp -= 1; /* &argc */ current->mm->start_stack = (unsigned long)sp & -FLAT_STACK_ALIGN; sp = (unsigned long __user *)current->mm->start_stack; if (put_user(bprm->argc, sp++)) return -EFAULT; if (IS_ENABLED(CONFIG_BINFMT_FLAT_ARGVP_ENVP_ON_STACK)) { unsigned long argv, envp; argv = (unsigned long)(sp + 2); envp = (unsigned long)(sp + 2 + bprm->argc + 1); if (put_user(argv, sp++) || put_user(envp, sp++)) return -EFAULT; } current->mm->arg_start = (unsigned long)p; for (i = bprm->argc; i > 0; i--) { if (put_user((unsigned long)p, sp++)) return -EFAULT; len = strnlen_user(p, MAX_ARG_STRLEN); if (!len || len > MAX_ARG_STRLEN) return -EINVAL; p += len; } if (put_user(0, sp++)) return -EFAULT; current->mm->arg_end = (unsigned long)p; current->mm->env_start = (unsigned long) p; for (i = bprm->envc; i > 0; i--) { if (put_user((unsigned long)p, sp++)) return -EFAULT; len = strnlen_user(p, MAX_ARG_STRLEN); if (!len || len > MAX_ARG_STRLEN) return -EINVAL; p += len; } if (put_user(0, sp++)) return -EFAULT; current->mm->env_end = (unsigned long)p; return 0;} /****************************************************************************/ #ifdef CONFIG_BINFMT_ZFLAT #include <linux/zlib.h> #define LBUFSIZE 4000 /* gzip flag byte */#define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */#define ORIG_NAME 0x08 /* bit 3 set: original file name present */#define COMMENT 0x10 /* bit 4 set: file comment present */#define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */#define RESERVED 0xC0 /* bit 6,7: reserved */ static int decompress_exec(struct linux_binprm *bprm, loff_t fpos, char *dst, long len, int fd){ unsigned char *buf; z_stream strm; int ret, retval; pr_debug("decompress_exec(offset=%llx,buf=%p,len=%lx)\n", fpos, dst, len); memset(&strm, 0, sizeof(strm)); strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL); if (!strm.workspace) return -ENOMEM; buf = kmalloc(LBUFSIZE, GFP_KERNEL); if (!buf) { retval = -ENOMEM; goto out_free; } /* Read in first chunk of data and parse gzip header. */ ret = kernel_read(bprm->file, buf, LBUFSIZE, &fpos); strm.next_in = buf; strm.avail_in = ret; strm.total_in = 0; retval = -ENOEXEC; /* Check minimum size -- gzip header */ if (ret < 10) { pr_debug("file too small?\n"); goto out_free_buf; } /* Check gzip magic number */ if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) { pr_debug("unknown compression magic?\n"); goto out_free_buf; } /* Check gzip method */ if (buf[2] != 8) { pr_debug("unknown compression method?\n"); goto out_free_buf; } /* Check gzip flags */ if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) || (buf[3] & RESERVED)) { pr_debug("unknown flags?\n"); goto out_free_buf; } ret = 10; if (buf[3] & EXTRA_FIELD) { ret += 2 + buf[10] + (buf[11] << 8); if (unlikely(ret >= LBUFSIZE)) { pr_debug("buffer overflow (EXTRA)?\n"); goto out_free_buf; } } if (buf[3] & ORIG_NAME) { while (ret < LBUFSIZE && buf[ret++] != 0) ; if (unlikely(ret == LBUFSIZE)) { pr_debug("buffer overflow (ORIG_NAME)?\n"); goto out_free_buf; } } if (buf[3] & COMMENT) { while (ret < LBUFSIZE && buf[ret++] != 0) ; if (unlikely(ret == LBUFSIZE)) { pr_debug("buffer overflow (COMMENT)?\n"); goto out_free_buf; } } strm.next_in += ret; strm.avail_in -= ret; strm.next_out = dst; strm.avail_out = len; strm.total_out = 0; if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) { pr_debug("zlib init failed?\n"); goto out_free_buf; } while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) { ret = kernel_read(bprm->file, buf, LBUFSIZE, &fpos); if (ret <= 0) break; len -= ret; strm.next_in = buf; strm.avail_in = ret; strm.total_in = 0; } if (ret < 0) { pr_debug("decompression failed (%d), %s\n", ret, strm.msg); goto out_zlib; } retval = 0;out_zlib: zlib_inflateEnd(&strm);out_free_buf: kfree(buf);out_free: kfree(strm.workspace); return retval;} #endif /* CONFIG_BINFMT_ZFLAT */ /****************************************************************************/ static unsigned longcalc_reloc(unsigned long r, struct lib_info *p){ unsigned long addr; unsigned long start_brk; unsigned long start_data; unsigned long text_len; unsigned long start_code; start_brk = p->lib_list[0].start_brk; start_data = p->lib_list[0].start_data; start_code = p->lib_list[0].start_code; text_len = p->lib_list[0].text_len; if (r > start_brk - start_data + text_len) { pr_err("reloc outside program 0x%lx (0 - 0x%lx/0x%lx)", r, start_brk-start_data+text_len, text_len); goto failed; } if (r < text_len) /* In text segment */ addr = r + start_code; else /* In data segment */ addr = r - text_len + start_data; /* Range checked already above so doing the range tests is redundant...*/ return addr; failed: pr_cont(", killing %s!\n", current->comm); send_sig(SIGSEGV, current, 0); return RELOC_FAILED;} /****************************************************************************/ #ifdef CONFIG_BINFMT_FLAT_OLDstatic void old_reloc(unsigned long rl){ static const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" }; flat_v2_reloc_t r; unsigned long __user *ptr; unsigned long val; r.value = rl;#if defined(CONFIG_COLDFIRE) ptr = (unsigned long __user *)(current->mm->start_code + r.reloc.offset);#else ptr = (unsigned long __user *)(current->mm->start_data + r.reloc.offset);#endif get_user(val, ptr); pr_debug("Relocation of variable at DATASEG+%x " "(address %p, currently %lx) into segment %s\n", r.reloc.offset, ptr, val, segment[r.reloc.type]); switch (r.reloc.type) { case OLD_FLAT_RELOC_TYPE_TEXT: val += current->mm->start_code; break; case OLD_FLAT_RELOC_TYPE_DATA: val += current->mm->start_data; break; case OLD_FLAT_RELOC_TYPE_BSS: val += current->mm->end_data; break; default: pr_err("Unknown relocation type=%x\n", r.reloc.type); break; } put_user(val, ptr); pr_debug("Relocation became %lx\n", val);}#endif /* CONFIG_BINFMT_FLAT_OLD */ /****************************************************************************/ static inline u32 __user *skip_got_header(u32 __user *rp){ if (IS_ENABLED(CONFIG_RISCV)) { /* * RISC-V has a 16 byte GOT PLT header for elf64-riscv * and 8 byte GOT PLT header for elf32-riscv. * Skip the whole GOT PLT header, since it is reserved * for the dynamic linker (ld.so). */ u32 rp_val0, rp_val1; if (get_user(rp_val0, rp)) return rp; if (get_user(rp_val1, rp + 1)) return rp; if (rp_val0 == 0xffffffff && rp_val1 == 0xffffffff) rp += 4; else if (rp_val0 == 0xffffffff) rp += 2; } return rp;} static int load_flat_file(struct linux_binprm *bprm, struct lib_info *libinfo, unsigned long *extra_stack){ struct flat_hdr *hdr; unsigned long textpos, datapos, realdatastart; u32 text_len, data_len, bss_len, stack_len, full_data, flags; unsigned long len, memp, memp_size, extra, rlim; __be32 __user *reloc; u32 __user *rp; int i, rev, relocs; loff_t fpos; unsigned long start_code, end_code; ssize_t result; int ret; hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */ text_len = ntohl(hdr->data_start); data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start); bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end); stack_len = ntohl(hdr->stack_size); if (extra_stack) { stack_len += *extra_stack; *extra_stack = stack_len; } relocs = ntohl(hdr->reloc_count); flags = ntohl(hdr->flags); rev = ntohl(hdr->rev); full_data = data_len + relocs * sizeof(unsigned long); if (strncmp(hdr->magic, "bFLT", 4)) { /* * Previously, here was a printk to tell people * "BINFMT_FLAT: bad header magic". * But for the kernel which also use ELF FD-PIC format, this * error message is confusing. * because a lot of people do not manage to produce good */ ret = -ENOEXEC; goto err; } if (flags & FLAT_FLAG_KTRACE) pr_info("Loading file: %s\n", bprm->filename); #ifdef CONFIG_BINFMT_FLAT_OLD if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) { pr_err("bad flat file version 0x%x (supported 0x%lx and 0x%lx)\n", rev, FLAT_VERSION, OLD_FLAT_VERSION); ret = -ENOEXEC; goto err; } /* * fix up the flags for the older format, there were all kinds * of endian hacks, this only works for the simple cases */ if (rev == OLD_FLAT_VERSION && (flags || IS_ENABLED(CONFIG_BINFMT_FLAT_OLD_ALWAYS_RAM))) flags = FLAT_FLAG_RAM; #else /* CONFIG_BINFMT_FLAT_OLD */ if (rev != FLAT_VERSION) { pr_err("bad flat file version 0x%x (supported 0x%lx)\n", rev, FLAT_VERSION); ret = -ENOEXEC; goto err; }#endif /* !CONFIG_BINFMT_FLAT_OLD */ /* * Make sure the header params are sane. * 28 bits (256 MB) is way more than reasonable in this case. * If some top bits are set we have probable binary corruption. */ if ((text_len | data_len | bss_len | stack_len | relocs | full_data) >> 28) { pr_err("bad header\n"); ret = -ENOEXEC; goto err; } #ifndef CONFIG_BINFMT_ZFLAT if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) { pr_err("Support for ZFLAT executables is not enabled.\n"); ret = -ENOEXEC; goto err; }#endif /* * Check initial limits. This avoids letting people circumvent * size limits imposed on them by creating programs with large * arrays in the data or bss. */ rlim = rlimit(RLIMIT_DATA);Lines 1–500 of 946. Load more
// SPDX-License-Identifier: GPL-2.0 /****************************************************************************/ /* * linux/fs/binfmt_flat.c * * Copyright (C) 2000-2003 David McCullough <davidm@snapgear.com> * Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com> * Copyright (C) 2002 SnapGear, by Paul Dale <pauli@snapgear.com> * Copyright (C) 2000, 2001 Lineo, by David McCullough <davidm@lineo.com> * based heavily on: * * linux/fs/binfmt_aout.c: * Copyright (C) 1991, 1992, 1996 Linus Torvalds * linux/fs/binfmt_flat.c for 2.0 kernel * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com> * JAN/99 -- coded full program relocation (gerg@snapgear.com) */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/kernel.h> #include <linux/sched.h> #include <linux/sched/task_stack.h> #include <linux/mm.h> #include <linux/mman.h> #include <linux/errno.h> #include <linux/signal.h> #include <linux/string.h> #include <linux/fs.h> #include <linux/file.h> #include <linux/ptrace.h> #include <linux/user.h> #include <linux/slab.h> #include <linux/binfmts.h> #include <linux/personality.h> #include <linux/init.h> #include <linux/flat.h> #include <linux/uaccess.h> #include <linux/vmalloc.h> #include <asm/byteorder.h> #include <linux/unaligned.h> #include <asm/cacheflush.h> #include <asm/page.h> #include <asm/flat.h> #ifndef flat_get_relocate_addr #define flat_get_relocate_addr(rel) (rel) #endif /****************************************************************************/ /* * User data (data section and bss) needs to be aligned. * We pick 0x20 here because it is the max value elf2flt has always * used in producing FLAT files, and because it seems to be large * enough to make all the gcc alignment related tests happy. */ #define FLAT_DATA_ALIGN (0x20) /* * User data (stack) also needs to be aligned. * Here we can be a bit looser than the data sections since this * needs to only meet arch ABI requirements. */ #define FLAT_STACK_ALIGN max_t(unsigned long, sizeof(void *), ARCH_SLAB_MINALIGN) #define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */ #define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */ #define MAX_SHARED_LIBS (1) #ifdef CONFIG_BINFMT_FLAT_NO_DATA_START_OFFSET #define DATA_START_OFFSET_WORDS (0) #define MAX_SHARED_LIBS_UPDATE (0) #else #define DATA_START_OFFSET_WORDS (MAX_SHARED_LIBS) #define MAX_SHARED_LIBS_UPDATE (MAX_SHARED_LIBS) #endif struct lib_info { struct { unsigned long start_code; /* Start of text segment */ unsigned long start_data; /* Start of data segment */ unsigned long start_brk; /* End of data segment */ unsigned long text_len; /* Length of text segment */ unsigned long entry; /* Start address for this module */ unsigned long build_date; /* When this one was compiled */ bool loaded; /* Has this library been loaded? */ } lib_list[MAX_SHARED_LIBS]; }; static int load_flat_binary(struct linux_binprm *); static struct linux_binfmt flat_format = { .module = THIS_MODULE, .load_binary = load_flat_binary, }; /****************************************************************************/ /* * create_flat_tables() parses the env- and arg-strings in new user * memory and creates the pointer tables from them, and puts their * addresses on the "stack", recording the new stack pointer value. */ static int create_flat_tables(struct linux_binprm *bprm, unsigned long arg_start) { char __user *p; unsigned long __user *sp; long i, len; p = (char __user *)arg_start; sp = (unsigned long __user *)current->mm->start_stack; sp -= bprm->envc + 1; sp -= bprm->argc + 1; if (IS_ENABLED(CONFIG_BINFMT_FLAT_ARGVP_ENVP_ON_STACK)) sp -= 2; /* argvp + envp */ sp -= 1; /* &argc */ current->mm->start_stack = (unsigned long)sp & -FLAT_STACK_ALIGN; sp = (unsigned long __user *)current->mm->start_stack; if (put_user(bprm->argc, sp++)) return -EFAULT; if (IS_ENABLED(CONFIG_BINFMT_FLAT_ARGVP_ENVP_ON_STACK)) { unsigned long argv, envp; argv = (unsigned long)(sp + 2); envp = (unsigned long)(sp + 2 + bprm->argc + 1); if (put_user(argv, sp++) || put_user(envp, sp++)) return -EFAULT; } current->mm->arg_start = (unsigned long)p; for (i = bprm->argc; i > 0; i--) { if (put_user((unsigned long)p, sp++)) return -EFAULT; len = strnlen_user(p, MAX_ARG_STRLEN); if (!len || len > MAX_ARG_STRLEN) return -EINVAL; p += len; } if (put_user(0, sp++)) return -EFAULT; current->mm->arg_end = (unsigned long)p; current->mm->env_start = (unsigned long) p; for (i = bprm->envc; i > 0; i--) { if (put_user((unsigned long)p, sp++)) return -EFAULT; len = strnlen_user(p, MAX_ARG_STRLEN); if (!len || len > MAX_ARG_STRLEN) return -EINVAL; p += len; } if (put_user(0, sp++)) return -EFAULT; current->mm->env_end = (unsigned long)p; return 0; } /****************************************************************************/ #ifdef CONFIG_BINFMT_ZFLAT #include <linux/zlib.h> #define LBUFSIZE 4000 /* gzip flag byte */ #define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */ #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */ #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ #define ORIG_NAME 0x08 /* bit 3 set: original file name present */ #define COMMENT 0x10 /* bit 4 set: file comment present */ #define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */ #define RESERVED 0xC0 /* bit 6,7: reserved */ static int decompress_exec(struct linux_binprm *bprm, loff_t fpos, char *dst, long len, int fd) { unsigned char *buf; z_stream strm; int ret, retval; pr_debug("decompress_exec(offset=%llx,buf=%p,len=%lx)\n", fpos, dst, len); memset(&strm, 0, sizeof(strm)); strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL); if (!strm.workspace) return -ENOMEM; buf = kmalloc(LBUFSIZE, GFP_KERNEL); if (!buf) { retval = -ENOMEM; goto out_free; } /* Read in first chunk of data and parse gzip header. */ ret = kernel_read(bprm->file, buf, LBUFSIZE, &fpos); strm.next_in = buf; strm.avail_in = ret; strm.total_in = 0; retval = -ENOEXEC; /* Check minimum size -- gzip header */ if (ret < 10) { pr_debug("file too small?\n"); goto out_free_buf; } /* Check gzip magic number */ if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) { pr_debug("unknown compression magic?\n"); goto out_free_buf; } /* Check gzip method */ if (buf[2] != 8) { pr_debug("unknown compression method?\n"); goto out_free_buf; } /* Check gzip flags */ if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) || (buf[3] & RESERVED)) { pr_debug("unknown flags?\n"); goto out_free_buf; } ret = 10; if (buf[3] & EXTRA_FIELD) { ret += 2 + buf[10] + (buf[11] << 8); if (unlikely(ret >= LBUFSIZE)) { pr_debug("buffer overflow (EXTRA)?\n"); goto out_free_buf; } } if (buf[3] & ORIG_NAME) { while (ret < LBUFSIZE && buf[ret++] != 0) ; if (unlikely(ret == LBUFSIZE)) { pr_debug("buffer overflow (ORIG_NAME)?\n"); goto out_free_buf; } } if (buf[3] & COMMENT) { while (ret < LBUFSIZE && buf[ret++] != 0) ; if (unlikely(ret == LBUFSIZE)) { pr_debug("buffer overflow (COMMENT)?\n"); goto out_free_buf; } } strm.next_in += ret; strm.avail_in -= ret; strm.next_out = dst; strm.avail_out = len; strm.total_out = 0; if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) { pr_debug("zlib init failed?\n"); goto out_free_buf; } while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) { ret = kernel_read(bprm->file, buf, LBUFSIZE, &fpos); if (ret <= 0) break; len -= ret; strm.next_in = buf; strm.avail_in = ret; strm.total_in = 0; } if (ret < 0) { pr_debug("decompression failed (%d), %s\n", ret, strm.msg); goto out_zlib; } retval = 0; out_zlib: zlib_inflateEnd(&strm); out_free_buf: kfree(buf); out_free: kfree(strm.workspace); return retval; } #endif /* CONFIG_BINFMT_ZFLAT */ /****************************************************************************/ static unsigned long calc_reloc(unsigned long r, struct lib_info *p) { unsigned long addr; unsigned long start_brk; unsigned long start_data; unsigned long text_len; unsigned long start_code; start_brk = p->lib_list[0].start_brk; start_data = p->lib_list[0].start_data; start_code = p->lib_list[0].start_code; text_len = p->lib_list[0].text_len; if (r > start_brk - start_data + text_len) { pr_err("reloc outside program 0x%lx (0 - 0x%lx/0x%lx)", r, start_brk-start_data+text_len, text_len); goto failed; } if (r < text_len) /* In text segment */ addr = r + start_code; else /* In data segment */ addr = r - text_len + start_data; /* Range checked already above so doing the range tests is redundant...*/ return addr; failed: pr_cont(", killing %s!\n", current->comm); send_sig(SIGSEGV, current, 0); return RELOC_FAILED; } /****************************************************************************/ #ifdef CONFIG_BINFMT_FLAT_OLD static void old_reloc(unsigned long rl) { static const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" }; flat_v2_reloc_t r; unsigned long __user *ptr; unsigned long val; r.value = rl; #if defined(CONFIG_COLDFIRE) ptr = (unsigned long __user *)(current->mm->start_code + r.reloc.offset); #else ptr = (unsigned long __user *)(current->mm->start_data + r.reloc.offset); #endif get_user(val, ptr); pr_debug("Relocation of variable at DATASEG+%x " "(address %p, currently %lx) into segment %s\n", r.reloc.offset, ptr, val, segment[r.reloc.type]); switch (r.reloc.type) { case OLD_FLAT_RELOC_TYPE_TEXT: val += current->mm->start_code; break; case OLD_FLAT_RELOC_TYPE_DATA: val += current->mm->start_data; break; case OLD_FLAT_RELOC_TYPE_BSS: val += current->mm->end_data; break; default: pr_err("Unknown relocation type=%x\n", r.reloc.type); break; } put_user(val, ptr); pr_debug("Relocation became %lx\n", val); } #endif /* CONFIG_BINFMT_FLAT_OLD */ /****************************************************************************/ static inline u32 __user *skip_got_header(u32 __user *rp) { if (IS_ENABLED(CONFIG_RISCV)) { /* * RISC-V has a 16 byte GOT PLT header for elf64-riscv * and 8 byte GOT PLT header for elf32-riscv. * Skip the whole GOT PLT header, since it is reserved * for the dynamic linker (ld.so). */ u32 rp_val0, rp_val1; if (get_user(rp_val0, rp)) return rp; if (get_user(rp_val1, rp + 1)) return rp; if (rp_val0 == 0xffffffff && rp_val1 == 0xffffffff) rp += 4; else if (rp_val0 == 0xffffffff) rp += 2; } return rp; } static int load_flat_file(struct linux_binprm *bprm, struct lib_info *libinfo, unsigned long *extra_stack) { struct flat_hdr *hdr; unsigned long textpos, datapos, realdatastart; u32 text_len, data_len, bss_len, stack_len, full_data, flags; unsigned long len, memp, memp_size, extra, rlim; __be32 __user *reloc; u32 __user *rp; int i, rev, relocs; loff_t fpos; unsigned long start_code, end_code; ssize_t result; int ret; hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */ text_len = ntohl(hdr->data_start); data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start); bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end); stack_len = ntohl(hdr->stack_size); if (extra_stack) { stack_len += *extra_stack; *extra_stack = stack_len; } relocs = ntohl(hdr->reloc_count); flags = ntohl(hdr->flags); rev = ntohl(hdr->rev); full_data = data_len + relocs * sizeof(unsigned long); if (strncmp(hdr->magic, "bFLT", 4)) { /* * Previously, here was a printk to tell people * "BINFMT_FLAT: bad header magic". * But for the kernel which also use ELF FD-PIC format, this * error message is confusing. * because a lot of people do not manage to produce good */ ret = -ENOEXEC; goto err; } if (flags & FLAT_FLAG_KTRACE) pr_info("Loading file: %s\n", bprm->filename); #ifdef CONFIG_BINFMT_FLAT_OLD if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) { pr_err("bad flat file version 0x%x (supported 0x%lx and 0x%lx)\n", rev, FLAT_VERSION, OLD_FLAT_VERSION); ret = -ENOEXEC; goto err; } /* * fix up the flags for the older format, there were all kinds * of endian hacks, this only works for the simple cases */ if (rev == OLD_FLAT_VERSION && (flags || IS_ENABLED(CONFIG_BINFMT_FLAT_OLD_ALWAYS_RAM))) flags = FLAT_FLAG_RAM; #else /* CONFIG_BINFMT_FLAT_OLD */ if (rev != FLAT_VERSION) { pr_err("bad flat file version 0x%x (supported 0x%lx)\n", rev, FLAT_VERSION); ret = -ENOEXEC; goto err; } #endif /* !CONFIG_BINFMT_FLAT_OLD */ /* * Make sure the header params are sane. * 28 bits (256 MB) is way more than reasonable in this case. * If some top bits are set we have probable binary corruption. */ if ((text_len | data_len | bss_len | stack_len | relocs | full_data) >> 28) { pr_err("bad header\n"); ret = -ENOEXEC; goto err; } #ifndef CONFIG_BINFMT_ZFLAT if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) { pr_err("Support for ZFLAT executables is not enabled.\n"); ret = -ENOEXEC; goto err; } #endif /* * Check initial limits. This avoids letting people circumvent * size limits imposed on them by creating programs with large * arrays in the data or bss. */ rlim = rlimit(RLIMIT_DATA);