diff options
Diffstat (limited to 'fs/binfmt_flat.c')
| -rw-r--r-- | fs/binfmt_flat.c | 236 |
1 files changed, 122 insertions, 114 deletions
diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c index 0498b181dd5..f723cd3a455 100644 --- a/fs/binfmt_flat.c +++ b/fs/binfmt_flat.c @@ -15,7 +15,7 @@ * JAN/99 -- coded full program relocation (gerg@snapgear.com) */ -#include <linux/module.h> +#include <linux/export.h> #include <linux/kernel.h> #include <linux/sched.h> #include <linux/mm.h> @@ -37,10 +37,10 @@ #include <linux/syscalls.h> #include <asm/byteorder.h> -#include <asm/system.h> #include <asm/uaccess.h> #include <asm/unaligned.h> #include <asm/cacheflush.h> +#include <asm/page.h> /****************************************************************************/ @@ -54,6 +54,21 @@ #define DBG_FLT(a...) #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 */ @@ -73,8 +88,8 @@ struct lib_info { static int load_flat_shared_library(int id, struct lib_info *p); #endif -static int load_flat_binary(struct linux_binprm *, struct pt_regs * regs); -static int flat_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit); +static int load_flat_binary(struct linux_binprm *); +static int flat_core_dump(struct coredump_params *cprm); static struct linux_binfmt flat_format = { .module = THIS_MODULE, @@ -89,10 +104,10 @@ static struct linux_binfmt flat_format = { * Currently only a stub-function. */ -static int flat_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit) +static int flat_core_dump(struct coredump_params *cprm) { printk("Process %s:%d received signr %d and should have core dumped\n", - current->comm, current->pid, (int) signr); + current->comm, current->pid, (int) cprm->siginfo->si_signo); return(1); } @@ -114,20 +129,18 @@ static unsigned long create_flat_tables( int envc = bprm->envc; char uninitialized_var(dummy); - sp = (unsigned long *) ((-(unsigned long)sizeof(char *))&(unsigned long) p); - - sp -= envc+1; - envp = sp; - sp -= argc+1; - argv = sp; + sp = (unsigned long *)p; + sp -= (envc + argc + 2) + 1 + (flat_argvp_envp_on_stack() ? 2 : 0); + sp = (unsigned long *) ((unsigned long)sp & -FLAT_STACK_ALIGN); + argv = sp + 1 + (flat_argvp_envp_on_stack() ? 2 : 0); + envp = argv + (argc + 1); - flat_stack_align(sp); if (flat_argvp_envp_on_stack()) { - --sp; put_user((unsigned long) envp, sp); - --sp; put_user((unsigned long) argv, sp); + put_user((unsigned long) envp, sp + 2); + put_user((unsigned long) argv, sp + 1); } - put_user(argc,--sp); + put_user(argc, sp); current->mm->arg_start = (unsigned long) p; while (argc-->0) { put_user((unsigned long) p, argv++); @@ -194,11 +207,12 @@ static int decompress_exec( /* Read in first chunk of data and parse gzip header. */ fpos = offset; - ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos); + ret = kernel_read(bprm->file, offset, buf, LBUFSIZE); strm.next_in = buf; strm.avail_in = ret; strm.total_in = 0; + fpos += ret; retval = -ENOEXEC; @@ -229,13 +243,13 @@ static int decompress_exec( ret = 10; if (buf[3] & EXTRA_FIELD) { ret += 2 + buf[10] + (buf[11] << 8); - if (unlikely(LBUFSIZE == ret)) { + if (unlikely(LBUFSIZE <= ret)) { DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n"); goto out_free_buf; } } if (buf[3] & ORIG_NAME) { - for (; ret < LBUFSIZE && (buf[ret] != 0); ret++) + while (ret < LBUFSIZE && buf[ret++] != 0) ; if (unlikely(LBUFSIZE == ret)) { DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n"); @@ -243,7 +257,7 @@ static int decompress_exec( } } if (buf[3] & COMMENT) { - for (; ret < LBUFSIZE && (buf[ret] != 0); ret++) + while (ret < LBUFSIZE && buf[ret++] != 0) ; if (unlikely(LBUFSIZE == ret)) { DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n"); @@ -264,16 +278,15 @@ static int decompress_exec( } while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) { - ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos); + ret = kernel_read(bprm->file, fpos, buf, LBUFSIZE); if (ret <= 0) break; - if (ret >= (unsigned long) -4096) - break; len -= ret; strm.next_in = buf; strm.avail_in = ret; strm.total_in = 0; + fpos += ret; } if (ret < 0) { @@ -324,7 +337,7 @@ calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp) "(%d != %d)", (unsigned) r, curid, id); goto failed; } else if ( ! p->lib_list[id].loaded && - load_flat_shared_library(id, p) > (unsigned long) -4096) { + IS_ERR_VALUE(load_flat_shared_library(id, p))) { printk("BINFMT_FLAT: failed to load library %d", id); goto failed; } @@ -346,7 +359,7 @@ calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp) if (!flat_reloc_valid(r, start_brk - start_data + text_len)) { printk("BINFMT_FLAT: reloc outside program 0x%x (0 - 0x%x/0x%x)", - (int) r,(int)(start_brk-start_code),(int)text_len); + (int) r,(int)(start_brk-start_data+text_len),(int)text_len); goto failed; } @@ -367,7 +380,7 @@ failed: /****************************************************************************/ -void old_reloc(unsigned long rl) +static void old_reloc(unsigned long rl) { #ifdef DEBUG char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" }; @@ -417,8 +430,9 @@ static int load_flat_file(struct linux_binprm * bprm, unsigned long textpos = 0, datapos = 0, result; unsigned long realdatastart = 0; unsigned long text_len, data_len, bss_len, stack_len, flags; - unsigned long len, reallen, memp = 0; - unsigned long extra, rlim; + unsigned long full_data; + unsigned long len, memp = 0; + unsigned long memp_size, extra, rlim; unsigned long *reloc = 0, *rp; struct inode *inode; int i, rev, relocs = 0; @@ -427,7 +441,7 @@ static int load_flat_file(struct linux_binprm * bprm, int ret; hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */ - inode = bprm->file->f_path.dentry->d_inode; + inode = file_inode(bprm->file); text_len = ntohl(hdr->data_start); data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start); @@ -440,6 +454,7 @@ static int load_flat_file(struct linux_binprm * bprm, 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)) { /* @@ -492,7 +507,7 @@ static int load_flat_file(struct linux_binprm * bprm, * size limits imposed on them by creating programs with large * arrays in the data or bss. */ - rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur; + rlim = rlimit(RLIMIT_DATA); if (rlim >= RLIM_INFINITY) rlim = ~0; if (data_len + bss_len > rlim) { @@ -510,6 +525,7 @@ static int load_flat_file(struct linux_binprm * bprm, /* OK, This is the point of no return */ set_personality(PER_LINUX_32BIT); + setup_new_exec(bprm); } /* @@ -530,10 +546,9 @@ static int load_flat_file(struct linux_binprm * bprm, */ DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n"); - down_write(¤t->mm->mmap_sem); - textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC, MAP_PRIVATE, 0); - up_write(¤t->mm->mmap_sem); - if (!textpos || textpos >= (unsigned long) -4096) { + textpos = vm_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC, + MAP_PRIVATE|MAP_EXECUTABLE, 0); + if (!textpos || IS_ERR_VALUE(textpos)) { if (!textpos) textpos = (unsigned long) -ENOMEM; printk("Unable to mmap process text, errno %d\n", (int)-textpos); @@ -542,29 +557,22 @@ static int load_flat_file(struct linux_binprm * bprm, } len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long); - down_write(¤t->mm->mmap_sem); - realdatastart = do_mmap(0, 0, len, + len = PAGE_ALIGN(len); + realdatastart = vm_mmap(0, 0, len, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0); - /* Remap to use all availabe slack region space */ - if (realdatastart && (realdatastart < (unsigned long)-4096)) { - reallen = ksize((void *)realdatastart); - if (reallen > len) { - realdatastart = do_mremap(realdatastart, len, - reallen, MREMAP_FIXED, realdatastart); - } - } - up_write(¤t->mm->mmap_sem); - if (realdatastart == 0 || realdatastart >= (unsigned long)-4096) { + if (realdatastart == 0 || IS_ERR_VALUE(realdatastart)) { if (!realdatastart) realdatastart = (unsigned long) -ENOMEM; printk("Unable to allocate RAM for process data, errno %d\n", (int)-realdatastart); - do_munmap(current->mm, textpos, text_len); + vm_munmap(textpos, text_len); ret = realdatastart; goto err; } - datapos = realdatastart + MAX_SHARED_LIBS * sizeof(unsigned long); + datapos = ALIGN(realdatastart + + MAX_SHARED_LIBS * sizeof(unsigned long), + FLAT_DATA_ALIGN); DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n", (int)(data_len + bss_len + stack_len), (int)datapos); @@ -573,41 +581,32 @@ static int load_flat_file(struct linux_binprm * bprm, #ifdef CONFIG_BINFMT_ZFLAT if (flags & FLAT_FLAG_GZDATA) { result = decompress_exec(bprm, fpos, (char *) datapos, - data_len + (relocs * sizeof(unsigned long)), 0); + full_data, 0); } else #endif { - result = bprm->file->f_op->read(bprm->file, (char *) datapos, - data_len + (relocs * sizeof(unsigned long)), &fpos); + result = read_code(bprm->file, datapos, fpos, + full_data); } - if (result >= (unsigned long)-4096) { + if (IS_ERR_VALUE(result)) { printk("Unable to read data+bss, errno %d\n", (int)-result); - do_munmap(current->mm, textpos, text_len); - do_munmap(current->mm, realdatastart, data_len + extra); + vm_munmap(textpos, text_len); + vm_munmap(realdatastart, len); ret = result; goto err; } reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len)); memp = realdatastart; - + memp_size = len; } else { len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long); - down_write(¤t->mm->mmap_sem); - textpos = do_mmap(0, 0, len, + len = PAGE_ALIGN(len); + textpos = vm_mmap(0, 0, len, PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0); - /* Remap to use all availabe slack region space */ - if (textpos && (textpos < (unsigned long) -4096)) { - reallen = ksize((void *)textpos); - if (reallen > len) { - textpos = do_mremap(textpos, len, reallen, - MREMAP_FIXED, textpos); - } - } - up_write(¤t->mm->mmap_sem); - if (!textpos || textpos >= (unsigned long) -4096) { + if (!textpos || IS_ERR_VALUE(textpos)) { if (!textpos) textpos = (unsigned long) -ENOMEM; printk("Unable to allocate RAM for process text/data, errno %d\n", @@ -617,11 +616,14 @@ static int load_flat_file(struct linux_binprm * bprm, } realdatastart = textpos + ntohl(hdr->data_start); - datapos = realdatastart + MAX_SHARED_LIBS * sizeof(unsigned long); - reloc = (unsigned long *) (textpos + ntohl(hdr->reloc_start) + - MAX_SHARED_LIBS * sizeof(unsigned long)); - memp = textpos; + datapos = ALIGN(realdatastart + + MAX_SHARED_LIBS * sizeof(unsigned long), + FLAT_DATA_ALIGN); + reloc = (unsigned long *) + (datapos + (ntohl(hdr->reloc_start) - text_len)); + memp = textpos; + memp_size = len; #ifdef CONFIG_BINFMT_ZFLAT /* * load it all in and treat it like a RAM load from now on @@ -629,34 +631,29 @@ static int load_flat_file(struct linux_binprm * bprm, if (flags & FLAT_FLAG_GZIP) { result = decompress_exec(bprm, sizeof (struct flat_hdr), (((char *) textpos) + sizeof (struct flat_hdr)), - (text_len + data_len + (relocs * sizeof(unsigned long)) + (text_len + full_data - sizeof (struct flat_hdr)), 0); memmove((void *) datapos, (void *) realdatastart, - data_len + (relocs * sizeof(unsigned long))); + full_data); } else if (flags & FLAT_FLAG_GZDATA) { - fpos = 0; - result = bprm->file->f_op->read(bprm->file, - (char *) textpos, text_len, &fpos); - if (result < (unsigned long) -4096) + result = read_code(bprm->file, textpos, 0, text_len); + if (!IS_ERR_VALUE(result)) result = decompress_exec(bprm, text_len, (char *) datapos, - data_len + (relocs * sizeof(unsigned long)), 0); + full_data, 0); } else #endif { - fpos = 0; - result = bprm->file->f_op->read(bprm->file, - (char *) textpos, text_len, &fpos); - if (result < (unsigned long) -4096) { - fpos = ntohl(hdr->data_start); - result = bprm->file->f_op->read(bprm->file, (char *) datapos, - data_len + (relocs * sizeof(unsigned long)), &fpos); - } + result = read_code(bprm->file, textpos, 0, text_len); + if (!IS_ERR_VALUE(result)) + result = read_code(bprm->file, datapos, + ntohl(hdr->data_start), + full_data); } - if (result >= (unsigned long)-4096) { + if (IS_ERR_VALUE(result)) { printk("Unable to read code+data+bss, errno %d\n",(int)-result); - do_munmap(current->mm, textpos, text_len + data_len + extra + + vm_munmap(textpos, text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long)); ret = result; goto err; @@ -679,10 +676,12 @@ static int load_flat_file(struct linux_binprm * bprm, * set up the brk stuff, uses any slack left in data/bss/stack * allocation. We put the brk after the bss (between the bss * and stack) like other platforms. + * Userspace code relies on the stack pointer starting out at + * an address right at the end of a page. */ current->mm->start_brk = datapos + data_len + bss_len; current->mm->brk = (current->mm->start_brk + 3) & ~3; - current->mm->context.end_brk = memp + ksize((void *) memp) - stack_len; + current->mm->context.end_brk = memp + memp_size - stack_len; } if (flags & FLAT_FLAG_KTRACE) @@ -710,7 +709,7 @@ static int load_flat_file(struct linux_binprm * bprm, * help simplify all this mumbo jumbo * * We've got two different sections of relocation entries. - * The first is the GOT which resides at the begining of the data segment + * The first is the GOT which resides at the beginning of the data segment * and is terminated with a -1. This one can be relocated in place. * The second is the extra relocation entries tacked after the image's * data segment. These require a little more processing as the entry is @@ -789,8 +788,8 @@ static int load_flat_file(struct linux_binprm * bprm, /* zero the BSS, BRK and stack areas */ memset((void*)(datapos + data_len), 0, bss_len + - (memp + ksize((void *) memp) - stack_len - /* end brk */ - libinfo->lib_list[id].start_brk) + /* start brk */ + (memp + memp_size - stack_len - /* end brk */ + libinfo->lib_list[id].start_brk) + /* start brk */ stack_len); return 0; @@ -813,6 +812,8 @@ static int load_flat_shared_library(int id, struct lib_info *libs) int res; char buf[16]; + memset(&bprm, 0, sizeof(bprm)); + /* Create the file name */ sprintf(buf, "/lib/lib%d.so", id); @@ -823,15 +824,28 @@ static int load_flat_shared_library(int id, struct lib_info *libs) if (IS_ERR(bprm.file)) return res; + bprm.cred = prepare_exec_creds(); + res = -ENOMEM; + if (!bprm.cred) + goto out; + + /* We don't really care about recalculating credentials at this point + * as we're past the point of no return and are dealing with shared + * libraries. + */ + bprm.cred_prepared = 1; + res = prepare_binprm(&bprm); - if (res <= (unsigned long)-4096) + if (!IS_ERR_VALUE(res)) res = load_flat_file(&bprm, libs, id, NULL); - if (bprm.file) { - allow_write_access(bprm.file); - fput(bprm.file); - bprm.file = NULL; - } + + abort_creds(bprm.cred); + +out: + allow_write_access(bprm.file); + fput(bprm.file); + return(res); } @@ -843,9 +857,10 @@ static int load_flat_shared_library(int id, struct lib_info *libs) * libraries. There is no binary dependent code anywhere else. */ -static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs) +static int load_flat_binary(struct linux_binprm * bprm) { struct lib_info libinfo; + struct pt_regs *regs = current_pt_regs(); unsigned long p = bprm->p; unsigned long stack_len; unsigned long start_addr; @@ -865,10 +880,10 @@ static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs) stack_len = TOP_OF_ARGS - bprm->p; /* the strings */ stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */ stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */ - + stack_len += FLAT_STACK_ALIGN - 1; /* reserve for upcoming alignment */ res = load_flat_file(bprm, &libinfo, 0, &stack_len); - if (res > (unsigned long)-4096) + if (IS_ERR_VALUE(res)) return res; /* Update data segment pointers for all libraries */ @@ -879,8 +894,7 @@ static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs) (libinfo.lib_list[j].loaded)? libinfo.lib_list[j].start_data:UNLOADED_LIB; - compute_creds(bprm); - current->flags &= ~PF_FORKNOEXEC; + install_exec_creds(bprm); set_binfmt(&flat_format); @@ -913,15 +927,14 @@ static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs) /* Stash our initial stack pointer into the mm structure */ current->mm->start_stack = (unsigned long )sp; - +#ifdef FLAT_PLAT_INIT + FLAT_PLAT_INIT(regs); +#endif DBG_FLT("start_thread(regs=0x%x, entry=0x%x, start_stack=0x%x)\n", (int)regs, (int)start_addr, (int)current->mm->start_stack); start_thread(regs, start_addr, current->mm->start_stack); - if (current->ptrace & PT_PTRACED) - send_sig(SIGTRAP, current, 0); - return 0; } @@ -929,17 +942,12 @@ static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs) static int __init init_flat_binfmt(void) { - return register_binfmt(&flat_format); -} - -static void __exit exit_flat_binfmt(void) -{ - unregister_binfmt(&flat_format); + register_binfmt(&flat_format); + return 0; } /****************************************************************************/ core_initcall(init_flat_binfmt); -module_exit(exit_flat_binfmt); /****************************************************************************/ |
