X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fbinfmt_aout.c;h=f96eff04e11ab4a8b23f7489ee4b0de50e67e152;hb=684bdc7ff95e0c1d4b0bcf236491840b55a54189;hp=72011826f0cb340aabc54f65ee7d31653fc7d364;hpb=404351e67a9facb475abf1492245374a28d13e90;p=safe%2Fjmp%2Flinux-2.6 diff --git a/fs/binfmt_aout.c b/fs/binfmt_aout.c index 7201182..f96eff0 100644 --- a/fs/binfmt_aout.c +++ b/fs/binfmt_aout.c @@ -20,20 +20,20 @@ #include #include #include -#include #include #include #include +#include +#include #include #include #include +#include static int load_aout_binary(struct linux_binprm *, struct pt_regs * regs); static int load_aout_library(struct file*); -static int aout_core_dump(long signr, struct pt_regs * regs, struct file *file); - -extern void dump_thread(struct pt_regs *, struct user *); +static int aout_core_dump(struct coredump_params *cprm); static struct linux_binfmt aout_format = { .module = THIS_MODULE, @@ -61,26 +61,6 @@ static int set_brk(unsigned long start, unsigned long end) } /* - * These are the only things you should do on a core-file: use only these - * macros to write out all the necessary info. - */ - -static int dump_write(struct file *file, const void *addr, int nr) -{ - return file->f_op->write(file, addr, nr, &file->f_pos) == nr; -} - -#define DUMP_WRITE(addr, nr) \ - if (!dump_write(file, (void *)(addr), (nr))) \ - goto end_coredump; - -#define DUMP_SEEK(offset) \ -if (file->f_op->llseek) { \ - if (file->f_op->llseek(file,(offset),0) != (offset)) \ - goto end_coredump; \ -} else file->f_pos = (offset) - -/* * Routine writes a core dump image in the current directory. * Currently only a stub-function. * @@ -90,107 +70,74 @@ if (file->f_op->llseek) { \ * dumping of the process results in another error.. */ -static int aout_core_dump(long signr, struct pt_regs * regs, struct file *file) +static int aout_core_dump(struct coredump_params *cprm) { + struct file *file = cprm->file; mm_segment_t fs; int has_dumped = 0; - unsigned long dump_start, dump_size; + void __user *dump_start; + int dump_size; struct user dump; -#if defined(__alpha__) -# define START_DATA(u) (u.start_data) -#elif defined(__arm__) -# define START_DATA(u) ((u.u_tsize << PAGE_SHIFT) + u.start_code) -#elif defined(__sparc__) -# define START_DATA(u) (u.u_tsize) -#elif defined(__i386__) || defined(__mc68000__) || defined(__arch_um__) -# define START_DATA(u) (u.u_tsize << PAGE_SHIFT) -#endif -#ifdef __sparc__ -# define START_STACK(u) ((regs->u_regs[UREG_FP]) & ~(PAGE_SIZE - 1)) +#ifdef __alpha__ +# define START_DATA(u) ((void __user *)u.start_data) #else -# define START_STACK(u) (u.start_stack) +# define START_DATA(u) ((void __user *)((u.u_tsize << PAGE_SHIFT) + \ + u.start_code)) #endif +# define START_STACK(u) ((void __user *)u.start_stack) fs = get_fs(); set_fs(KERNEL_DS); has_dumped = 1; current->flags |= PF_DUMPCORE; strncpy(dump.u_comm, current->comm, sizeof(dump.u_comm)); -#ifndef __sparc__ - dump.u_ar0 = (void *)(((unsigned long)(&dump.regs)) - ((unsigned long)(&dump))); -#endif - dump.signal = signr; - dump_thread(regs, &dump); + dump.u_ar0 = offsetof(struct user, regs); + dump.signal = cprm->signr; + aout_dump_thread(cprm->regs, &dump); /* If the size of the dump file exceeds the rlimit, then see what would happen if we wrote the stack, but not the data area. */ -#ifdef __sparc__ - if ((dump.u_dsize+dump.u_ssize) > - current->signal->rlim[RLIMIT_CORE].rlim_cur) - dump.u_dsize = 0; -#else - if ((dump.u_dsize+dump.u_ssize+1) * PAGE_SIZE > - current->signal->rlim[RLIMIT_CORE].rlim_cur) + if ((dump.u_dsize + dump.u_ssize+1) * PAGE_SIZE > cprm->limit) dump.u_dsize = 0; -#endif /* Make sure we have enough room to write the stack and data areas. */ -#ifdef __sparc__ - if ((dump.u_ssize) > - current->signal->rlim[RLIMIT_CORE].rlim_cur) - dump.u_ssize = 0; -#else - if ((dump.u_ssize+1) * PAGE_SIZE > - current->signal->rlim[RLIMIT_CORE].rlim_cur) + if ((dump.u_ssize + 1) * PAGE_SIZE > cprm->limit) dump.u_ssize = 0; -#endif /* make sure we actually have a data and stack area to dump */ set_fs(USER_DS); -#ifdef __sparc__ - if (!access_ok(VERIFY_READ, (void __user *)START_DATA(dump), dump.u_dsize)) - dump.u_dsize = 0; - if (!access_ok(VERIFY_READ, (void __user *)START_STACK(dump), dump.u_ssize)) - dump.u_ssize = 0; -#else - if (!access_ok(VERIFY_READ, (void __user *)START_DATA(dump), dump.u_dsize << PAGE_SHIFT)) + if (!access_ok(VERIFY_READ, START_DATA(dump), dump.u_dsize << PAGE_SHIFT)) dump.u_dsize = 0; - if (!access_ok(VERIFY_READ, (void __user *)START_STACK(dump), dump.u_ssize << PAGE_SHIFT)) + if (!access_ok(VERIFY_READ, START_STACK(dump), dump.u_ssize << PAGE_SHIFT)) dump.u_ssize = 0; -#endif set_fs(KERNEL_DS); /* struct user */ - DUMP_WRITE(&dump,sizeof(dump)); + if (!dump_write(file, &dump, sizeof(dump))) + goto end_coredump; /* Now dump all of the user data. Include malloced stuff as well */ -#ifndef __sparc__ - DUMP_SEEK(PAGE_SIZE); -#endif + if (!dump_seek(cprm->file, PAGE_SIZE - sizeof(dump))) + goto end_coredump; /* now we start writing out the user space info */ set_fs(USER_DS); /* Dump the data area */ if (dump.u_dsize != 0) { dump_start = START_DATA(dump); -#ifdef __sparc__ - dump_size = dump.u_dsize; -#else dump_size = dump.u_dsize << PAGE_SHIFT; -#endif - DUMP_WRITE(dump_start,dump_size); + if (!dump_write(file, dump_start, dump_size)) + goto end_coredump; } /* Now prepare to dump the stack area */ if (dump.u_ssize != 0) { dump_start = START_STACK(dump); -#ifdef __sparc__ - dump_size = dump.u_ssize; -#else dump_size = dump.u_ssize << PAGE_SHIFT; -#endif - DUMP_WRITE(dump_start,dump_size); + if (!dump_write(file, dump_start, dump_size)) + goto end_coredump; } /* Finally dump the task struct. Not be used by gdb, but could be useful */ set_fs(KERNEL_DS); - DUMP_WRITE(current,sizeof(*current)); + if (!dump_write(file, current, sizeof(*current))) + goto end_coredump; end_coredump: set_fs(fs); return has_dumped; @@ -210,29 +157,24 @@ static unsigned long __user *create_aout_tables(char __user *p, struct linux_bin int envc = bprm->envc; sp = (void __user *)((-(unsigned long)sizeof(char *)) & (unsigned long) p); -#ifdef __sparc__ - /* This imposes the proper stack alignment for a new process. */ - sp = (void __user *) (((unsigned long) sp) & ~7); - if ((envc+argc+3)&1) --sp; -#endif #ifdef __alpha__ /* whee.. test-programs are so much fun. */ put_user(0, --sp); put_user(0, --sp); if (bprm->loader) { put_user(0, --sp); - put_user(0x3eb, --sp); + put_user(1003, --sp); put_user(bprm->loader, --sp); - put_user(0x3ea, --sp); + put_user(1002, --sp); } put_user(bprm->exec, --sp); - put_user(0x3e9, --sp); + put_user(1001, --sp); #endif sp -= envc+1; envp = (char __user * __user *) sp; sp -= argc+1; argv = (char __user * __user *) sp; -#if defined(__i386__) || defined(__mc68000__) || defined(__arm__) || defined(__arch_um__) +#ifndef __alpha__ put_user((unsigned long) envp,--sp); put_user((unsigned long) argv,--sp); #endif @@ -276,17 +218,24 @@ static int load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs) if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC && N_MAGIC(ex) != QMAGIC && N_MAGIC(ex) != NMAGIC) || N_TRSIZE(ex) || N_DRSIZE(ex) || - i_size_read(bprm->file->f_dentry->d_inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) { + i_size_read(bprm->file->f_path.dentry->d_inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) { return -ENOEXEC; } + /* + * Requires a mmap handler. This prevents people from using a.out + * as part of an exploit attack against /proc-related vulnerabilities. + */ + if (!bprm->file->f_op || !bprm->file->f_op->mmap) + return -ENOEXEC; + fd_offset = N_TXTOFF(ex); /* 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 = current->signal->rlim[RLIMIT_DATA].rlim_cur; + rlim = rlimit(RLIMIT_DATA); if (rlim >= RLIM_INFINITY) rlim = ~0; if (ex.a_data + ex.a_bss > rlim) @@ -298,16 +247,12 @@ static int load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs) return retval; /* OK, This is the point of no return */ -#if defined(__alpha__) +#ifdef __alpha__ SET_AOUT_PERSONALITY(bprm, ex); -#elif defined(__sparc__) - set_personality(PER_SUNOS); -#if !defined(__sparc_v9__) - memcpy(¤t->thread.core_exec, &ex, sizeof(struct exec)); -#endif #else set_personality(PER_LINUX); #endif + setup_new_exec(bprm); current->mm->end_code = ex.a_text + (current->mm->start_code = N_TXTADDR(ex)); @@ -318,27 +263,8 @@ static int load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs) current->mm->free_area_cache = current->mm->mmap_base; current->mm->cached_hole_size = 0; - current->mm->mmap = NULL; - compute_creds(bprm); + install_exec_creds(bprm); current->flags &= ~PF_FORKNOEXEC; -#ifdef __sparc__ - if (N_MAGIC(ex) == NMAGIC) { - loff_t pos = fd_offset; - /* Fuck me plenty... */ - /* */ - down_write(¤t->mm->mmap_sem); - error = do_brk(N_TXTADDR(ex), ex.a_text); - up_write(¤t->mm->mmap_sem); - bprm->file->f_op->read(bprm->file, (char *) N_TXTADDR(ex), - ex.a_text, &pos); - down_write(¤t->mm->mmap_sem); - error = do_brk(N_DATADDR(ex), ex.a_data); - up_write(¤t->mm->mmap_sem); - bprm->file->f_op->read(bprm->file, (char *) N_DATADDR(ex), - ex.a_data, &pos); - goto beyond_if; - } -#endif if (N_MAGIC(ex) == OMAGIC) { unsigned long text_addr, map_size; @@ -346,7 +272,7 @@ static int load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs) text_addr = N_TXTADDR(ex); -#if defined(__alpha__) || defined(__sparc__) +#ifdef __alpha__ pos = fd_offset; map_size = ex.a_text+ex.a_data + PAGE_SIZE - 1; #else @@ -371,21 +297,17 @@ static int load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs) flush_icache_range(text_addr, text_addr+ex.a_text+ex.a_data); } else { - static unsigned long error_time, error_time2; if ((ex.a_text & 0xfff || ex.a_data & 0xfff) && - (N_MAGIC(ex) != NMAGIC) && (jiffies-error_time2) > 5*HZ) + (N_MAGIC(ex) != NMAGIC) && printk_ratelimit()) { printk(KERN_NOTICE "executable not page aligned\n"); - error_time2 = jiffies; } - if ((fd_offset & ~PAGE_MASK) != 0 && - (jiffies-error_time) > 5*HZ) + if ((fd_offset & ~PAGE_MASK) != 0 && printk_ratelimit()) { printk(KERN_WARNING "fd_offset is not page aligned. Please convert program: %s\n", - bprm->file->f_dentry->d_name.name); - error_time = jiffies; + bprm->file->f_path.dentry->d_name.name); } if (!bprm->file->f_op->mmap||((fd_offset & ~PAGE_MASK) != 0)) { @@ -447,12 +369,6 @@ beyond_if: regs->gp = ex.a_gpvalue; #endif start_thread(regs, ex.a_entry, current->mm->start_stack); - if (unlikely(current->ptrace & PT_PTRACED)) { - if (current->ptrace & PT_TRACE_EXEC) - ptrace_notify ((PTRACE_EVENT_EXEC << 8) | SIGTRAP); - else - send_sig(SIGTRAP, current, 0); - } return 0; } @@ -464,7 +380,7 @@ static int load_aout_library(struct file *file) int retval; struct exec ex; - inode = file->f_dentry->d_inode; + inode = file->f_path.dentry->d_inode; retval = -ENOEXEC; error = kernel_read(file, 0, (char *) &ex, sizeof(ex)); @@ -478,6 +394,13 @@ static int load_aout_library(struct file *file) goto out; } + /* + * Requires a mmap handler. This prevents people from using a.out + * as part of an exploit attack against /proc-related vulnerabilities. + */ + if (!file->f_op || !file->f_op->mmap) + goto out; + if (N_FLAGS(ex)) goto out; @@ -487,15 +410,13 @@ static int load_aout_library(struct file *file) start_addr = ex.a_entry & 0xfffff000; if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) { - static unsigned long error_time; loff_t pos = N_TXTOFF(ex); - if ((jiffies-error_time) > 5*HZ) + if (printk_ratelimit()) { printk(KERN_WARNING "N_TXTOFF is not page aligned. Please convert library: %s\n", - file->f_dentry->d_name.name); - error_time = jiffies; + file->f_path.dentry->d_name.name); } down_write(¤t->mm->mmap_sem); do_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);