diff options
Diffstat (limited to 'fs/exec.c')
| -rw-r--r-- | fs/exec.c | 494 |
1 files changed, 199 insertions, 295 deletions
diff --git a/fs/exec.c b/fs/exec.c index 8b9011b6704..a3d33fe592d 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -26,6 +26,7 @@ #include <linux/file.h> #include <linux/fdtable.h> #include <linux/mm.h> +#include <linux/vmacache.h> #include <linux/stat.h> #include <linux/fcntl.h> #include <linux/swap.h> @@ -62,7 +63,6 @@ #include <trace/events/task.h> #include "internal.h" -#include "coredump.h" #include <trace/events/sched.h> @@ -74,6 +74,8 @@ static DEFINE_RWLOCK(binfmt_lock); void __register_binfmt(struct linux_binfmt * fmt, int insert) { BUG_ON(!fmt); + if (WARN_ON(!fmt->load_binary)) + return; write_lock(&binfmt_lock); insert ? list_add(&fmt->lh, &formats) : list_add_tail(&fmt->lh, &formats); @@ -96,6 +98,7 @@ static inline void put_binfmt(struct linux_binfmt * fmt) module_put(fmt->module); } +#ifdef CONFIG_USELIB /* * Note that a shared library must be both readable and executable due to * security reasons. @@ -104,26 +107,28 @@ static inline void put_binfmt(struct linux_binfmt * fmt) */ SYSCALL_DEFINE1(uselib, const char __user *, library) { + struct linux_binfmt *fmt; struct file *file; struct filename *tmp = getname(library); int error = PTR_ERR(tmp); static const struct open_flags uselib_flags = { .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC, .acc_mode = MAY_READ | MAY_EXEC | MAY_OPEN, - .intent = LOOKUP_OPEN + .intent = LOOKUP_OPEN, + .lookup_flags = LOOKUP_FOLLOW, }; if (IS_ERR(tmp)) goto out; - file = do_filp_open(AT_FDCWD, tmp, &uselib_flags, LOOKUP_FOLLOW); + file = do_filp_open(AT_FDCWD, tmp, &uselib_flags); putname(tmp); error = PTR_ERR(file); if (IS_ERR(file)) goto out; error = -EINVAL; - if (!S_ISREG(file->f_path.dentry->d_inode->i_mode)) + if (!S_ISREG(file_inode(file)->i_mode)) goto exit; error = -EACCES; @@ -133,29 +138,27 @@ SYSCALL_DEFINE1(uselib, const char __user *, library) fsnotify_open(file); error = -ENOEXEC; - if(file->f_op) { - struct linux_binfmt * fmt; - read_lock(&binfmt_lock); - list_for_each_entry(fmt, &formats, lh) { - if (!fmt->load_shlib) - continue; - if (!try_module_get(fmt->module)) - continue; - read_unlock(&binfmt_lock); - error = fmt->load_shlib(file); - read_lock(&binfmt_lock); - put_binfmt(fmt); - if (error != -ENOEXEC) - break; - } + read_lock(&binfmt_lock); + list_for_each_entry(fmt, &formats, lh) { + if (!fmt->load_shlib) + continue; + if (!try_module_get(fmt->module)) + continue; read_unlock(&binfmt_lock); + error = fmt->load_shlib(file); + read_lock(&binfmt_lock); + put_binfmt(fmt); + if (error != -ENOEXEC) + break; } + read_unlock(&binfmt_lock); exit: fput(file); out: return error; } +#endif /* #ifdef CONFIG_USELIB */ #ifdef CONFIG_MMU /* @@ -265,7 +268,7 @@ static int __bprm_mm_init(struct linux_binprm *bprm) BUILD_BUG_ON(VM_STACK_FLAGS & VM_STACK_INCOMPLETE_SETUP); vma->vm_end = STACK_TOP_MAX; vma->vm_start = vma->vm_end - PAGE_SIZE; - vma->vm_flags = VM_STACK_FLAGS | VM_STACK_INCOMPLETE_SETUP; + vma->vm_flags = VM_SOFTDIRTY | VM_STACK_FLAGS | VM_STACK_INCOMPLETE_SETUP; vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); INIT_LIST_HEAD(&vma->anon_vma_chain); @@ -355,7 +358,7 @@ static bool valid_arg_len(struct linux_binprm *bprm, long len) * flags, permissions, and offset, so we use temporary values. We'll update * them later in setup_arg_pages(). */ -int bprm_mm_init(struct linux_binprm *bprm) +static int bprm_mm_init(struct linux_binprm *bprm) { int err; struct mm_struct *mm = NULL; @@ -434,8 +437,9 @@ static int count(struct user_arg_ptr argv, int max) if (IS_ERR(p)) return -EFAULT; - if (i++ >= max) + if (i >= max) return -E2BIG; + ++i; if (fatal_signal_pending(current)) return -ERESTARTNOHAND; @@ -606,13 +610,13 @@ static int shift_arg_pages(struct vm_area_struct *vma, unsigned long shift) return -ENOMEM; lru_add_drain(); - tlb_gather_mmu(&tlb, mm, 0); + tlb_gather_mmu(&tlb, mm, old_start, old_end); if (new_end > old_start) { /* * when the old and new regions overlap clear from new_end. */ free_pgd_range(&tlb, new_end, old_end, new_end, - vma->vm_next ? vma->vm_next->vm_start : 0); + vma->vm_next ? vma->vm_next->vm_start : USER_PGTABLES_CEILING); } else { /* * otherwise, clean from old_start; this is done to not touch @@ -621,9 +625,9 @@ static int shift_arg_pages(struct vm_area_struct *vma, unsigned long shift) * for the others its just a little faster. */ free_pgd_range(&tlb, old_start, old_end, new_end, - vma->vm_next ? vma->vm_next->vm_start : 0); + vma->vm_next ? vma->vm_next->vm_start : USER_PGTABLES_CEILING); } - tlb_finish_mmu(&tlb, new_end, old_end); + tlb_finish_mmu(&tlb, old_start, old_end); /* * Shrink the vma to just the new range. Always succeeds. @@ -653,10 +657,10 @@ int setup_arg_pages(struct linux_binprm *bprm, unsigned long rlim_stack; #ifdef CONFIG_STACK_GROWSUP - /* Limit stack size to 1GB */ + /* Limit stack size */ stack_base = rlimit_max(RLIMIT_STACK); - if (stack_base > (1 << 30)) - stack_base = 1 << 30; + if (stack_base > STACK_SIZE_MAX) + stack_base = STACK_SIZE_MAX; /* Make sure we didn't let the argument array grow too large. */ if (vma->vm_end - vma->vm_start > stack_base) @@ -747,23 +751,23 @@ EXPORT_SYMBOL(setup_arg_pages); #endif /* CONFIG_MMU */ -struct file *open_exec(const char *name) +static struct file *do_open_exec(struct filename *name) { struct file *file; int err; - struct filename tmp = { .name = name }; static const struct open_flags open_exec_flags = { .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC, .acc_mode = MAY_EXEC | MAY_OPEN, - .intent = LOOKUP_OPEN + .intent = LOOKUP_OPEN, + .lookup_flags = LOOKUP_FOLLOW, }; - file = do_filp_open(AT_FDCWD, &tmp, &open_exec_flags, LOOKUP_FOLLOW); + file = do_filp_open(AT_FDCWD, name, &open_exec_flags); if (IS_ERR(file)) goto out; err = -EACCES; - if (!S_ISREG(file->f_path.dentry->d_inode->i_mode)) + if (!S_ISREG(file_inode(file)->i_mode)) goto exit; if (file->f_path.mnt->mnt_flags & MNT_NOEXEC) @@ -782,6 +786,12 @@ exit: fput(file); return ERR_PTR(err); } + +struct file *open_exec(const char *name) +{ + struct filename tmp = { .name = name }; + return do_open_exec(&tmp); +} EXPORT_SYMBOL(open_exec); int kernel_read(struct file *file, loff_t offset, @@ -801,10 +811,19 @@ int kernel_read(struct file *file, loff_t offset, EXPORT_SYMBOL(kernel_read); +ssize_t read_code(struct file *file, unsigned long addr, loff_t pos, size_t len) +{ + ssize_t res = vfs_read(file, (void __user *)addr, len, &pos); + if (res > 0) + flush_icache_range(addr, addr + len); + return res; +} +EXPORT_SYMBOL(read_code); + static int exec_mmap(struct mm_struct *mm) { struct task_struct *tsk; - struct mm_struct * old_mm, *active_mm; + struct mm_struct *old_mm, *active_mm; /* Notify parent that we're no longer interested in the old VM */ tsk = current; @@ -830,8 +849,9 @@ static int exec_mmap(struct mm_struct *mm) tsk->mm = mm; tsk->active_mm = mm; activate_mm(active_mm, mm); + tsk->mm->vmacache_seqnum = 0; + vmacache_flush(tsk); task_unlock(tsk); - arch_pick_mmap_layout(mm); if (old_mm) { up_read(&old_mm->mmap_sem); BUG_ON(active_mm != old_mm); @@ -897,11 +917,13 @@ static int de_thread(struct task_struct *tsk) sig->notify_count = -1; /* for exit_notify() */ for (;;) { + threadgroup_change_begin(tsk); write_lock_irq(&tasklist_lock); if (likely(leader->exit_state)) break; __set_current_state(TASK_KILLABLE); write_unlock_irq(&tasklist_lock); + threadgroup_change_end(tsk); schedule(); if (unlikely(__fatal_signal_pending(tsk))) goto killed; @@ -918,6 +940,7 @@ static int de_thread(struct task_struct *tsk) * also take its birthdate (always earlier than our own). */ tsk->start_time = leader->start_time; + tsk->real_start_time = leader->real_start_time; BUG_ON(!same_thread_group(leader, tsk)); BUG_ON(has_group_leader_pid(tsk)); @@ -933,9 +956,8 @@ static int de_thread(struct task_struct *tsk) * Note: The old leader also uses this pid until release_task * is called. Odd but simple and correct. */ - detach_pid(tsk, PIDTYPE_PID); tsk->pid = leader->pid; - attach_pid(tsk, PIDTYPE_PID, task_pid(leader)); + change_pid(tsk, PIDTYPE_PID, task_pid(leader)); transfer_pid(leader, tsk, PIDTYPE_PGID); transfer_pid(leader, tsk, PIDTYPE_SID); @@ -959,6 +981,7 @@ static int de_thread(struct task_struct *tsk) if (unlikely(leader->ptrace)) __wake_up_parent(leader, leader->parent); write_unlock_irq(&tasklist_lock); + threadgroup_change_end(tsk); release_task(leader); } @@ -1023,38 +1046,13 @@ EXPORT_SYMBOL_GPL(get_task_comm); * so that a new one can be started */ -void set_task_comm(struct task_struct *tsk, char *buf) +void __set_task_comm(struct task_struct *tsk, const char *buf, bool exec) { task_lock(tsk); - trace_task_rename(tsk, buf); - - /* - * Threads may access current->comm without holding - * the task lock, so write the string carefully. - * Readers without a lock may see incomplete new - * names but are safe from non-terminating string reads. - */ - memset(tsk->comm, 0, TASK_COMM_LEN); - wmb(); strlcpy(tsk->comm, buf, sizeof(tsk->comm)); task_unlock(tsk); - perf_event_comm(tsk); -} - -static void filename_to_taskname(char *tcomm, const char *fn, unsigned int len) -{ - int i, ch; - - /* Copies the binary name from after last slash */ - for (i = 0; (ch = *(fn++)) != '\0';) { - if (ch == '/') - i = 0; /* overwrite what we wrote */ - else - if (i < len - 1) - tcomm[i++] = ch; - } - tcomm[i] = '\0'; + perf_event_comm(tsk, exec); } int flush_old_exec(struct linux_binprm * bprm) @@ -1070,8 +1068,6 @@ int flush_old_exec(struct linux_binprm * bprm) goto out; set_mm_exe_file(bprm->mm, bprm->file); - - filename_to_taskname(bprm->tcomm, bprm->filename, sizeof(bprm->tcomm)); /* * Release all of the old mmap stuff */ @@ -1083,7 +1079,8 @@ int flush_old_exec(struct linux_binprm * bprm) bprm->mm = NULL; /* We're using it now */ set_fs(USER_DS); - current->flags &= ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD); + current->flags &= ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD | + PF_NOFREEZE | PF_NO_SETAFFINITY); flush_thread(); current->personality &= ~bprm->per_clear; @@ -1096,7 +1093,7 @@ EXPORT_SYMBOL(flush_old_exec); void would_dump(struct linux_binprm *bprm, struct file *file) { - if (inode_permission(file->f_path.dentry->d_inode, MAY_READ) < 0) + if (inode_permission(file_inode(file), MAY_READ) < 0) bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP; } EXPORT_SYMBOL(would_dump); @@ -1109,11 +1106,12 @@ void setup_new_exec(struct linux_binprm * bprm) current->sas_ss_sp = current->sas_ss_size = 0; if (uid_eq(current_euid(), current_uid()) && gid_eq(current_egid(), current_gid())) - set_dumpable(current->mm, SUID_DUMPABLE_ENABLED); + set_dumpable(current->mm, SUID_DUMP_USER); else set_dumpable(current->mm, suid_dumpable); - set_task_comm(current, bprm->tcomm); + perf_event_exec(); + __set_task_comm(current, kbasename(bprm->filename), true); /* Set the new mm task size. We have to do that late because it may * depend on TIF_32BIT which is only updated in flush_thread() on @@ -1131,18 +1129,9 @@ void setup_new_exec(struct linux_binprm * bprm) set_dumpable(current->mm, suid_dumpable); } - /* - * Flush performance counters when crossing a - * security domain: - */ - if (!get_dumpable(current->mm)) - perf_event_exit_task(current); - /* An exec changes our domain. We are no longer part of the thread group */ - current->self_exec_id++; - flush_signal_handlers(current, 0); do_close_on_exec(current->files); } @@ -1167,16 +1156,35 @@ int prepare_bprm_creds(struct linux_binprm *bprm) return -ENOMEM; } -void free_bprm(struct linux_binprm *bprm) +static void free_bprm(struct linux_binprm *bprm) { free_arg_pages(bprm); if (bprm->cred) { mutex_unlock(¤t->signal->cred_guard_mutex); abort_creds(bprm->cred); } + if (bprm->file) { + allow_write_access(bprm->file); + fput(bprm->file); + } + /* If a binfmt changed the interp, free it. */ + if (bprm->interp != bprm->filename) + kfree(bprm->interp); kfree(bprm); } +int bprm_change_interp(char *interp, struct linux_binprm *bprm) +{ + /* If a binfmt changed the interp, free it first. */ + if (bprm->interp != bprm->filename) + kfree(bprm->interp); + bprm->interp = kstrdup(interp, GFP_KERNEL); + if (!bprm->interp) + return -ENOMEM; + return 0; +} +EXPORT_SYMBOL(bprm_change_interp); + /* * install the new credentials for this executable */ @@ -1186,6 +1194,15 @@ void install_exec_creds(struct linux_binprm *bprm) commit_creds(bprm->cred); bprm->cred = NULL; + + /* + * Disable monitoring for regular users + * when executing setuid binaries. Must + * wait until new credentials are committed + * by commit_creds() above + */ + if (get_dumpable(current->mm) != SUID_DUMP_USER) + perf_event_exit_task(current); /* * cred_guard_mutex must be held at least to this point to prevent * ptrace_attach() from altering our determination of the task's @@ -1201,11 +1218,10 @@ EXPORT_SYMBOL(install_exec_creds); * - the caller must hold ->cred_guard_mutex to protect against * PTRACE_ATTACH */ -static int check_unsafe_exec(struct linux_binprm *bprm) +static void check_unsafe_exec(struct linux_binprm *bprm) { struct task_struct *p = current, *t; unsigned n_fs; - int res = 0; if (p->ptrace) { if (p->ptrace & PT_PTRACE_CAP) @@ -1221,58 +1237,48 @@ static int check_unsafe_exec(struct linux_binprm *bprm) if (current->no_new_privs) bprm->unsafe |= LSM_UNSAFE_NO_NEW_PRIVS; + t = p; n_fs = 1; spin_lock(&p->fs->lock); rcu_read_lock(); - for (t = next_thread(p); t != p; t = next_thread(t)) { + while_each_thread(p, t) { if (t->fs == p->fs) n_fs++; } rcu_read_unlock(); - if (p->fs->users > n_fs) { + if (p->fs->users > n_fs) bprm->unsafe |= LSM_UNSAFE_SHARE; - } else { - res = -EAGAIN; - if (!p->fs->in_exec) { - p->fs->in_exec = 1; - res = 1; - } - } + else + p->fs->in_exec = 1; spin_unlock(&p->fs->lock); - - return res; } -/* - * Fill the binprm structure from the inode. +/* + * Fill the binprm structure from the inode. * Check permissions, then read the first 128 (BINPRM_BUF_SIZE) bytes * * This may be called multiple times for binary chains (scripts for example). */ int prepare_binprm(struct linux_binprm *bprm) { - umode_t mode; - struct inode * inode = bprm->file->f_path.dentry->d_inode; + struct inode *inode = file_inode(bprm->file); + umode_t mode = inode->i_mode; int retval; - mode = inode->i_mode; - if (bprm->file->f_op == NULL) - return -EACCES; /* clear any previous set[ug]id data from a previous binary */ bprm->cred->euid = current_euid(); bprm->cred->egid = current_egid(); if (!(bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) && - !current->no_new_privs) { + !current->no_new_privs && + kuid_has_mapping(bprm->cred->user_ns, inode->i_uid) && + kgid_has_mapping(bprm->cred->user_ns, inode->i_gid)) { /* Set-uid? */ if (mode & S_ISUID) { - if (!kuid_has_mapping(bprm->cred->user_ns, inode->i_uid)) - return -EPERM; bprm->per_clear |= PER_CLEAR_ON_SETID; bprm->cred->euid = inode->i_uid; - } /* Set-gid? */ @@ -1282,8 +1288,6 @@ int prepare_binprm(struct linux_binprm *bprm) * executable. */ if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) { - if (!kgid_has_mapping(bprm->cred->user_ns, inode->i_gid)) - return -EPERM; bprm->per_clear |= PER_CLEAR_ON_SETID; bprm->cred->egid = inode->i_gid; } @@ -1345,23 +1349,62 @@ out: } EXPORT_SYMBOL(remove_arg_zero); +#define printable(c) (((c)=='\t') || ((c)=='\n') || (0x20<=(c) && (c)<=0x7e)) /* * cycle the list of binary formats handler, until one recognizes the image */ -int search_binary_handler(struct linux_binprm *bprm,struct pt_regs *regs) +int search_binary_handler(struct linux_binprm *bprm) { - unsigned int depth = bprm->recursion_depth; - int try,retval; + bool need_retry = IS_ENABLED(CONFIG_MODULES); struct linux_binfmt *fmt; - pid_t old_pid, old_vpid; + int retval; + + /* This allows 4 levels of binfmt rewrites before failing hard. */ + if (bprm->recursion_depth > 5) + return -ELOOP; retval = security_bprm_check(bprm); if (retval) return retval; - retval = audit_bprm(bprm); - if (retval) - return retval; + retval = -ENOENT; + retry: + read_lock(&binfmt_lock); + list_for_each_entry(fmt, &formats, lh) { + if (!try_module_get(fmt->module)) + continue; + read_unlock(&binfmt_lock); + bprm->recursion_depth++; + retval = fmt->load_binary(bprm); + bprm->recursion_depth--; + if (retval >= 0 || retval != -ENOEXEC || + bprm->mm == NULL || bprm->file == NULL) { + put_binfmt(fmt); + return retval; + } + read_lock(&binfmt_lock); + put_binfmt(fmt); + } + read_unlock(&binfmt_lock); + + if (need_retry && retval == -ENOEXEC) { + if (printable(bprm->buf[0]) && printable(bprm->buf[1]) && + printable(bprm->buf[2]) && printable(bprm->buf[3])) + return retval; + if (request_module("binfmt-%04x", *(ushort *)(bprm->buf + 2)) < 0) + return retval; + need_retry = false; + goto retry; + } + + return retval; +} +EXPORT_SYMBOL(search_binary_handler); + +static int exec_binprm(struct linux_binprm *bprm) +{ + pid_t old_pid, old_vpid; + int ret; /* Need to fetch pid before load_binary changes it */ old_pid = current->pid; @@ -1369,84 +1412,31 @@ int search_binary_handler(struct linux_binprm *bprm,struct pt_regs *regs) old_vpid = task_pid_nr_ns(current, task_active_pid_ns(current->parent)); rcu_read_unlock(); - retval = -ENOENT; - for (try=0; try<2; try++) { - read_lock(&binfmt_lock); - list_for_each_entry(fmt, &formats, lh) { - int (*fn)(struct linux_binprm *, struct pt_regs *) = fmt->load_binary; - if (!fn) - continue; - if (!try_module_get(fmt->module)) - continue; - read_unlock(&binfmt_lock); - retval = fn(bprm, regs); - /* - * Restore the depth counter to its starting value - * in this call, so we don't have to rely on every - * load_binary function to restore it on return. - */ - bprm->recursion_depth = depth; - if (retval >= 0) { - if (depth == 0) { - trace_sched_process_exec(current, old_pid, bprm); - ptrace_event(PTRACE_EVENT_EXEC, old_vpid); - } - put_binfmt(fmt); - allow_write_access(bprm->file); - if (bprm->file) - fput(bprm->file); - bprm->file = NULL; - current->did_exec = 1; - proc_exec_connector(current); - return retval; - } - read_lock(&binfmt_lock); - put_binfmt(fmt); - if (retval != -ENOEXEC || bprm->mm == NULL) - break; - if (!bprm->file) { - read_unlock(&binfmt_lock); - return retval; - } - } - read_unlock(&binfmt_lock); -#ifdef CONFIG_MODULES - if (retval != -ENOEXEC || bprm->mm == NULL) { - break; - } else { -#define printable(c) (((c)=='\t') || ((c)=='\n') || (0x20<=(c) && (c)<=0x7e)) - if (printable(bprm->buf[0]) && - printable(bprm->buf[1]) && - printable(bprm->buf[2]) && - printable(bprm->buf[3])) - break; /* -ENOEXEC */ - if (try) - break; /* -ENOEXEC */ - request_module("binfmt-%04x", *(unsigned short *)(&bprm->buf[2])); - } -#else - break; -#endif + ret = search_binary_handler(bprm); + if (ret >= 0) { + audit_bprm(bprm); + trace_sched_process_exec(current, old_pid, bprm); + ptrace_event(PTRACE_EVENT_EXEC, old_vpid); + proc_exec_connector(current); } - return retval; -} -EXPORT_SYMBOL(search_binary_handler); + return ret; +} /* * sys_execve() executes a new program. */ -static int do_execve_common(const char *filename, +static int do_execve_common(struct filename *filename, struct user_arg_ptr argv, - struct user_arg_ptr envp, - struct pt_regs *regs) + struct user_arg_ptr envp) { struct linux_binprm *bprm; struct file *file; struct files_struct *displaced; - bool clear_in_exec; int retval; - const struct cred *cred = current_cred(); + + if (IS_ERR(filename)) + return PTR_ERR(filename); /* * We move the actual failure in case of RLIMIT_NPROC excess from @@ -1455,7 +1445,7 @@ static int do_execve_common(const char *filename, * whether NPROC limit is still exceeded. */ if ((current->flags & PF_NPROC_EXCEEDED) && - atomic_read(&cred->user->processes) > rlimit(RLIMIT_NPROC)) { + atomic_read(¤t_user()->processes) > rlimit(RLIMIT_NPROC)) { retval = -EAGAIN; goto out_ret; } @@ -1477,13 +1467,10 @@ static int do_execve_common(const char *filename, if (retval) goto out_free; - retval = check_unsafe_exec(bprm); - if (retval < 0) - goto out_free; - clear_in_exec = retval; + check_unsafe_exec(bprm); current->in_execve = 1; - file = open_exec(filename); + file = do_open_exec(filename); retval = PTR_ERR(file); if (IS_ERR(file)) goto out_unmark; @@ -1491,12 +1478,11 @@ static int do_execve_common(const char *filename, sched_exec(); bprm->file = file; - bprm->filename = filename; - bprm->interp = filename; + bprm->filename = bprm->interp = filename->name; retval = bprm_mm_init(bprm); if (retval) - goto out_file; + goto out_unmark; bprm->argc = count(argv, MAX_ARG_STRINGS); if ((retval = bprm->argc) < 0) @@ -1523,7 +1509,7 @@ static int do_execve_common(const char *filename, if (retval < 0) goto out; - retval = search_binary_handler(bprm,regs); + retval = exec_binprm(bprm); if (retval < 0) goto out; @@ -1531,7 +1517,9 @@ static int do_execve_common(const char *filename, current->fs->in_exec = 0; current->in_execve = 0; acct_update_integrals(current); + task_numa_free(current); free_bprm(bprm); + putname(filename); if (displaced) put_files_struct(displaced); return retval; @@ -1542,15 +1530,8 @@ out: mmput(bprm->mm); } -out_file: - if (bprm->file) { - allow_write_access(bprm->file); - fput(bprm->file); - } - out_unmark: - if (clear_in_exec) - current->fs->in_exec = 0; + current->fs->in_exec = 0; current->in_execve = 0; out_free: @@ -1560,24 +1541,23 @@ out_files: if (displaced) reset_files_struct(displaced); out_ret: + putname(filename); return retval; } -int do_execve(const char *filename, +int do_execve(struct filename *filename, const char __user *const __user *__argv, - const char __user *const __user *__envp, - struct pt_regs *regs) + const char __user *const __user *__envp) { struct user_arg_ptr argv = { .ptr.native = __argv }; struct user_arg_ptr envp = { .ptr.native = __envp }; - return do_execve_common(filename, argv, envp, regs); + return do_execve_common(filename, argv, envp); } #ifdef CONFIG_COMPAT -int compat_do_execve(const char *filename, +static int compat_do_execve(struct filename *filename, const compat_uptr_t __user *__argv, - const compat_uptr_t __user *__envp, - struct pt_regs *regs) + const compat_uptr_t __user *__envp) { struct user_arg_ptr argv = { .is_compat = true, @@ -1587,7 +1567,7 @@ int compat_do_execve(const char *filename, .is_compat = true, .ptr.compat = __envp, }; - return do_execve_common(filename, argv, envp, regs); + return do_execve_common(filename, argv, envp); } #endif @@ -1602,112 +1582,36 @@ void set_binfmt(struct linux_binfmt *new) if (new) __module_get(new->module); } - EXPORT_SYMBOL(set_binfmt); /* - * set_dumpable converts traditional three-value dumpable to two flags and - * stores them into mm->flags. It modifies lower two bits of mm->flags, but - * these bits are not changed atomically. So get_dumpable can observe the - * intermediate state. To avoid doing unexpected behavior, get get_dumpable - * return either old dumpable or new one by paying attention to the order of - * modifying the bits. - * - * dumpable | mm->flags (binary) - * old new | initial interim final - * ---------+----------------------- - * 0 1 | 00 01 01 - * 0 2 | 00 10(*) 11 - * 1 0 | 01 00 00 - * 1 2 | 01 11 11 - * 2 0 | 11 10(*) 00 - * 2 1 | 11 11 01 - * - * (*) get_dumpable regards interim value of 10 as 11. + * set_dumpable stores three-value SUID_DUMP_* into mm->flags. */ void set_dumpable(struct mm_struct *mm, int value) { - switch (value) { - case SUID_DUMPABLE_DISABLED: - clear_bit(MMF_DUMPABLE, &mm->flags); - smp_wmb(); - clear_bit(MMF_DUMP_SECURELY, &mm->flags); - break; - case SUID_DUMPABLE_ENABLED: - set_bit(MMF_DUMPABLE, &mm->flags); - smp_wmb(); - clear_bit(MMF_DUMP_SECURELY, &mm->flags); - break; - case SUID_DUMPABLE_SAFE: - set_bit(MMF_DUMP_SECURELY, &mm->flags); - smp_wmb(); - set_bit(MMF_DUMPABLE, &mm->flags); - break; - } -} - -int __get_dumpable(unsigned long mm_flags) -{ - int ret; + unsigned long old, new; - ret = mm_flags & MMF_DUMPABLE_MASK; - return (ret > SUID_DUMPABLE_ENABLED) ? SUID_DUMPABLE_SAFE : ret; -} + if (WARN_ON((unsigned)value > SUID_DUMP_ROOT)) + return; -int get_dumpable(struct mm_struct *mm) -{ - return __get_dumpable(mm->flags); + do { + old = ACCESS_ONCE(mm->flags); + new = (old & ~MMF_DUMPABLE_MASK) | value; + } while (cmpxchg(&mm->flags, old, new) != old); } -#ifdef __ARCH_WANT_SYS_EXECVE SYSCALL_DEFINE3(execve, const char __user *, filename, const char __user *const __user *, argv, const char __user *const __user *, envp) { - struct filename *path = getname(filename); - int error = PTR_ERR(path); - if (!IS_ERR(path)) { - error = do_execve(path->name, argv, envp, current_pt_regs()); - putname(path); - } - return error; + return do_execve(getname(filename), argv, envp); } #ifdef CONFIG_COMPAT -asmlinkage long compat_sys_execve(const char __user * filename, - const compat_uptr_t __user * argv, - const compat_uptr_t __user * envp) -{ - struct filename *path = getname(filename); - int error = PTR_ERR(path); - if (!IS_ERR(path)) { - error = compat_do_execve(path->name, argv, envp, - current_pt_regs()); - putname(path); - } - return error; -} -#endif -#endif - -#ifdef __ARCH_WANT_KERNEL_EXECVE -int kernel_execve(const char *filename, - const char *const argv[], - const char *const envp[]) +COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename, + const compat_uptr_t __user *, argv, + const compat_uptr_t __user *, envp) { - struct pt_regs *p = current_pt_regs(); - int ret; - - ret = do_execve(filename, - (const char __user *const __user *)argv, - (const char __user *const __user *)envp, p); - if (ret < 0) - return ret; - - /* - * We were successful. We won't be returning to our caller, but - * instead to user space by manipulating the kernel stack. - */ - ret_from_kernel_execve(p); + return compat_do_execve(getname(filename), argv, envp); } #endif |
