From 7714d5985bb7101a90fb427dc29dc592cf1b960e Mon Sep 17 00:00:00 2001 From: Pavel Machek Date: Tue, 7 Feb 2006 12:58:22 -0800 Subject: [PATCH] swsusp: kill unneeded/unbalanced bio_get - Remove unneeded bio_get() which would cause a bio leak - Writing doesn't dirty pages. Reading dirties pages. - We should dirty the pages after the IO completion, not before (Busy-waiting for disk I/O completion isn't very polite.) Signed-off-by: Pavel Machek Cc: "Rafael J. Wysocki" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/power/swsusp.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'kernel') diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c index 59c91c148e82..4e90905f0e87 100644 --- a/kernel/power/swsusp.c +++ b/kernel/power/swsusp.c @@ -743,7 +743,6 @@ static int submit(int rw, pgoff_t page_off, void *page) if (!bio) return -ENOMEM; bio->bi_sector = page_off * (PAGE_SIZE >> 9); - bio_get(bio); bio->bi_bdev = resume_bdev; bio->bi_end_io = end_io; @@ -753,14 +752,13 @@ static int submit(int rw, pgoff_t page_off, void *page) goto Done; } - if (rw == WRITE) - bio_set_pages_dirty(bio); atomic_set(&io_done, 1); submit_bio(rw | (1 << BIO_RW_SYNC), bio); while (atomic_read(&io_done)) yield(); - + if (rw == READ) + bio_set_pages_dirty(bio); Done: bio_put(bio); return error; -- cgit v1.3-6-gb490 From 8e08b756869eeb08ace17ad64c2a8cb97b18e856 Mon Sep 17 00:00:00 2001 From: Andrew Morton Date: Tue, 7 Feb 2006 12:58:45 -0800 Subject: [PATCH] module: strlen_user() race fix Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/module.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'kernel') diff --git a/kernel/module.c b/kernel/module.c index e058aedf6b93..5aad477ddc79 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1670,6 +1670,9 @@ static struct module *load_module(void __user *umod, goto free_mod; } + /* Userspace could have altered the string after the strlen_user() */ + args[arglen - 1] = '\0'; + if (find_module(mod->name)) { err = -EEXIST; goto free_mod; -- cgit v1.3-6-gb490 From 46cd2f32baf181b74b16cceb123bab6fe1f61f85 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 7 Feb 2006 12:58:50 -0800 Subject: [PATCH] Fix build failure in recent pm_prepare_* changes. Fix compilation problem in PM headers. Signed-off-by: Rafael J. Wysocki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/suspend.h | 10 +++++++++- kernel/power/console.c | 4 +++- kernel/power/power.h | 16 ---------------- 3 files changed, 12 insertions(+), 18 deletions(-) (limited to 'kernel') diff --git a/include/linux/suspend.h b/include/linux/suspend.h index 43bcd13eb1ec..37c1c76fd547 100644 --- a/include/linux/suspend.h +++ b/include/linux/suspend.h @@ -42,13 +42,21 @@ extern void mark_free_pages(struct zone *zone); #ifdef CONFIG_PM /* kernel/power/swsusp.c */ extern int software_suspend(void); + +#if defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE) +extern int pm_prepare_console(void); +extern void pm_restore_console(void); +#else +static inline int pm_prepare_console(void) { return 0; } +static inline void pm_restore_console(void) {} +#endif /* defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE) */ #else static inline int software_suspend(void) { printk("Warning: fake suspend called\n"); return -EPERM; } -#endif +#endif /* CONFIG_PM */ #ifdef CONFIG_SUSPEND_SMP extern void disable_nonboot_cpus(void); diff --git a/kernel/power/console.c b/kernel/power/console.c index 579d239d129f..623786d44159 100644 --- a/kernel/power/console.c +++ b/kernel/power/console.c @@ -9,7 +9,9 @@ #include #include "power.h" -#ifdef SUSPEND_CONSOLE +#if defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE) +#define SUSPEND_CONSOLE (MAX_NR_CONSOLES-1) + static int orig_fgconsole, orig_kmsg; int pm_prepare_console(void) diff --git a/kernel/power/power.h b/kernel/power/power.h index d8f0d1a76bae..388dba680841 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -1,14 +1,6 @@ #include #include -/* With SUSPEND_CONSOLE defined suspend looks *really* cool, but - we probably do not take enough locks for switching consoles, etc, - so bad things might happen. -*/ -#if defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE) -#define SUSPEND_CONSOLE (MAX_NR_CONSOLES-1) -#endif - struct swsusp_info { struct new_utsname uts; u32 version_code; @@ -42,14 +34,6 @@ static struct subsys_attribute _name##_attr = { \ extern struct subsystem power_subsys; -#ifdef SUSPEND_CONSOLE -extern int pm_prepare_console(void); -extern void pm_restore_console(void); -#else -static int pm_prepare_console(void) { return 0; } -static void pm_restore_console(void) {} -#endif - /* References to section boundaries */ extern const void __nosave_begin, __nosave_end; -- cgit v1.3-6-gb490 From cf2e340f4249b781b3d2beb41e891d08581f0e10 Mon Sep 17 00:00:00 2001 From: JANAK DESAI Date: Tue, 7 Feb 2006 12:58:58 -0800 Subject: [PATCH] unshare system call -v5: system call handler function sys_unshare system call handler function accepts the same flags as clone system call, checks constraints on each of the flags and invokes corresponding unshare functions to disassociate respective process context if it was being shared with another task. Here is the link to a program for testing unshare system call. http://prdownloads.sourceforge.net/audit/unshare_test.c?download Please note that because of a problem in rmdir associated with bind mounts and clone with CLONE_NEWNS, the test fails while trying to remove temporary test directory. You can remove that temporary directory by doing rmdir, twice, from the command line. The first will fail with EBUSY, but the second will succeed. I have reported the problem to Ram Pai and Al Viro with a small program which reproduces the problem. Al told us yesterday that he will be looking at the problem soon. I have tried multiple rmdirs from the unshare_test program itself, but for some reason that is not working. Doing two rmdirs from command line does seem to remove the directory. Signed-off-by: Janak Desai Cc: Al Viro Cc: Christoph Hellwig Cc: Michael Kerrisk Cc: Andi Kleen Cc: Paul Mackerras Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/fork.c | 232 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 232 insertions(+) (limited to 'kernel') diff --git a/kernel/fork.c b/kernel/fork.c index 7f0ab5ee948c..6eb9362775f9 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1323,3 +1323,235 @@ void __init proc_caches_init(void) sizeof(struct mm_struct), ARCH_MIN_MMSTRUCT_ALIGN, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL); } + + +/* + * Check constraints on flags passed to the unshare system call and + * force unsharing of additional process context as appropriate. + */ +static inline void check_unshare_flags(unsigned long *flags_ptr) +{ + /* + * If unsharing a thread from a thread group, must also + * unshare vm. + */ + if (*flags_ptr & CLONE_THREAD) + *flags_ptr |= CLONE_VM; + + /* + * If unsharing vm, must also unshare signal handlers. + */ + if (*flags_ptr & CLONE_VM) + *flags_ptr |= CLONE_SIGHAND; + + /* + * If unsharing signal handlers and the task was created + * using CLONE_THREAD, then must unshare the thread + */ + if ((*flags_ptr & CLONE_SIGHAND) && + (atomic_read(¤t->signal->count) > 1)) + *flags_ptr |= CLONE_THREAD; + + /* + * If unsharing namespace, must also unshare filesystem information. + */ + if (*flags_ptr & CLONE_NEWNS) + *flags_ptr |= CLONE_FS; +} + +/* + * Unsharing of tasks created with CLONE_THREAD is not supported yet + */ +static int unshare_thread(unsigned long unshare_flags) +{ + if (unshare_flags & CLONE_THREAD) + return -EINVAL; + + return 0; +} + +/* + * Unsharing of fs info for tasks created with CLONE_FS is not supported yet + */ +static int unshare_fs(unsigned long unshare_flags, struct fs_struct **new_fsp) +{ + struct fs_struct *fs = current->fs; + + if ((unshare_flags & CLONE_FS) && + (fs && atomic_read(&fs->count) > 1)) + return -EINVAL; + + return 0; +} + +/* + * Unsharing of namespace for tasks created without CLONE_NEWNS is not + * supported yet + */ +static int unshare_namespace(unsigned long unshare_flags, struct namespace **new_nsp) +{ + struct namespace *ns = current->namespace; + + if ((unshare_flags & CLONE_NEWNS) && + (ns && atomic_read(&ns->count) > 1)) + return -EINVAL; + + return 0; +} + +/* + * Unsharing of sighand for tasks created with CLONE_SIGHAND is not + * supported yet + */ +static int unshare_sighand(unsigned long unshare_flags, struct sighand_struct **new_sighp) +{ + struct sighand_struct *sigh = current->sighand; + + if ((unshare_flags & CLONE_SIGHAND) && + (sigh && atomic_read(&sigh->count) > 1)) + return -EINVAL; + else + return 0; +} + +/* + * Unsharing of vm for tasks created with CLONE_VM is not supported yet + */ +static int unshare_vm(unsigned long unshare_flags, struct mm_struct **new_mmp) +{ + struct mm_struct *mm = current->mm; + + if ((unshare_flags & CLONE_VM) && + (mm && atomic_read(&mm->mm_users) > 1)) + return -EINVAL; + + return 0; + +} + +/* + * Unsharing of files for tasks created with CLONE_FILES is not supported yet + */ +static int unshare_fd(unsigned long unshare_flags, struct files_struct **new_fdp) +{ + struct files_struct *fd = current->files; + + if ((unshare_flags & CLONE_FILES) && + (fd && atomic_read(&fd->count) > 1)) + return -EINVAL; + + return 0; +} + +/* + * Unsharing of semundo for tasks created with CLONE_SYSVSEM is not + * supported yet + */ +static int unshare_semundo(unsigned long unshare_flags, struct sem_undo_list **new_ulistp) +{ + if (unshare_flags & CLONE_SYSVSEM) + return -EINVAL; + + return 0; +} + +/* + * unshare allows a process to 'unshare' part of the process + * context which was originally shared using clone. copy_* + * functions used by do_fork() cannot be used here directly + * because they modify an inactive task_struct that is being + * constructed. Here we are modifying the current, active, + * task_struct. + */ +asmlinkage long sys_unshare(unsigned long unshare_flags) +{ + int err = 0; + struct fs_struct *fs, *new_fs = NULL; + struct namespace *ns, *new_ns = NULL; + struct sighand_struct *sigh, *new_sigh = NULL; + struct mm_struct *mm, *new_mm = NULL, *active_mm = NULL; + struct files_struct *fd, *new_fd = NULL; + struct sem_undo_list *new_ulist = NULL; + + check_unshare_flags(&unshare_flags); + + if ((err = unshare_thread(unshare_flags))) + goto bad_unshare_out; + if ((err = unshare_fs(unshare_flags, &new_fs))) + goto bad_unshare_cleanup_thread; + if ((err = unshare_namespace(unshare_flags, &new_ns))) + goto bad_unshare_cleanup_fs; + if ((err = unshare_sighand(unshare_flags, &new_sigh))) + goto bad_unshare_cleanup_ns; + if ((err = unshare_vm(unshare_flags, &new_mm))) + goto bad_unshare_cleanup_sigh; + if ((err = unshare_fd(unshare_flags, &new_fd))) + goto bad_unshare_cleanup_vm; + if ((err = unshare_semundo(unshare_flags, &new_ulist))) + goto bad_unshare_cleanup_fd; + + if (new_fs || new_ns || new_sigh || new_mm || new_fd || new_ulist) { + + task_lock(current); + + if (new_fs) { + fs = current->fs; + current->fs = new_fs; + new_fs = fs; + } + + if (new_ns) { + ns = current->namespace; + current->namespace = new_ns; + new_ns = ns; + } + + if (new_sigh) { + sigh = current->sighand; + current->sighand = new_sigh; + new_sigh = sigh; + } + + if (new_mm) { + mm = current->mm; + active_mm = current->active_mm; + current->mm = new_mm; + current->active_mm = new_mm; + activate_mm(active_mm, new_mm); + new_mm = mm; + } + + if (new_fd) { + fd = current->files; + current->files = new_fd; + new_fd = fd; + } + + task_unlock(current); + } + +bad_unshare_cleanup_fd: + if (new_fd) + put_files_struct(new_fd); + +bad_unshare_cleanup_vm: + if (new_mm) + mmput(new_mm); + +bad_unshare_cleanup_sigh: + if (new_sigh) + if (atomic_dec_and_test(&new_sigh->count)) + kmem_cache_free(sighand_cachep, new_sigh); + +bad_unshare_cleanup_ns: + if (new_ns) + put_namespace(new_ns); + +bad_unshare_cleanup_fs: + if (new_fs) + put_fs_struct(new_fs); + +bad_unshare_cleanup_thread: +bad_unshare_out: + return err; +} -- cgit v1.3-6-gb490 From 99d1419d96d7df9cfa56bc977810be831bd5ef64 Mon Sep 17 00:00:00 2001 From: JANAK DESAI Date: Tue, 7 Feb 2006 12:58:59 -0800 Subject: [PATCH] unshare system call -v5: unshare filesystem info If filesystem structure is being shared, allocate a new one and copy information from the current, shared, structure. Signed-off-by: Janak Desai Cc: Al Viro Cc: Christoph Hellwig Cc: Michael Kerrisk Cc: Andi Kleen Cc: Paul Mackerras Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/fork.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'kernel') diff --git a/kernel/fork.c b/kernel/fork.c index 6eb9362775f9..598e5c27242c 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1371,15 +1371,18 @@ static int unshare_thread(unsigned long unshare_flags) } /* - * Unsharing of fs info for tasks created with CLONE_FS is not supported yet + * Unshare the filesystem structure if it is being shared */ static int unshare_fs(unsigned long unshare_flags, struct fs_struct **new_fsp) { struct fs_struct *fs = current->fs; if ((unshare_flags & CLONE_FS) && - (fs && atomic_read(&fs->count) > 1)) - return -EINVAL; + (fs && atomic_read(&fs->count) > 1)) { + *new_fsp = __copy_fs_struct(current->fs); + if (!*new_fsp) + return -ENOMEM; + } return 0; } -- cgit v1.3-6-gb490 From 741a295130606143edbf9fc740f633dbc1e6225f Mon Sep 17 00:00:00 2001 From: JANAK DESAI Date: Tue, 7 Feb 2006 12:59:00 -0800 Subject: [PATCH] unshare system call -v5: unshare namespace If the namespace structure is being shared, allocate a new one and copy information from the current, shared, structure. Signed-off-by: Janak Desai Cc: Al Viro Cc: Christoph Hellwig Cc: Michael Kerrisk Cc: Andi Kleen Cc: Paul Mackerras Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/namespace.c | 56 ++++++++++++++++++++++++++++++----------------- include/linux/namespace.h | 1 + kernel/fork.c | 17 +++++++++----- 3 files changed, 48 insertions(+), 26 deletions(-) (limited to 'kernel') diff --git a/fs/namespace.c b/fs/namespace.c index ce97becff461..a2bef5c81033 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1325,27 +1325,17 @@ dput_out: return retval; } -int copy_namespace(int flags, struct task_struct *tsk) +/* + * Allocate a new namespace structure and populate it with contents + * copied from the namespace of the passed in task structure. + */ +struct namespace *dup_namespace(struct task_struct *tsk, struct fs_struct *fs) { struct namespace *namespace = tsk->namespace; struct namespace *new_ns; struct vfsmount *rootmnt = NULL, *pwdmnt = NULL, *altrootmnt = NULL; - struct fs_struct *fs = tsk->fs; struct vfsmount *p, *q; - if (!namespace) - return 0; - - get_namespace(namespace); - - if (!(flags & CLONE_NEWNS)) - return 0; - - if (!capable(CAP_SYS_ADMIN)) { - put_namespace(namespace); - return -EPERM; - } - new_ns = kmalloc(sizeof(struct namespace), GFP_KERNEL); if (!new_ns) goto out; @@ -1396,8 +1386,6 @@ int copy_namespace(int flags, struct task_struct *tsk) } up_write(&namespace_sem); - tsk->namespace = new_ns; - if (rootmnt) mntput(rootmnt); if (pwdmnt) @@ -1405,12 +1393,40 @@ int copy_namespace(int flags, struct task_struct *tsk) if (altrootmnt) mntput(altrootmnt); - put_namespace(namespace); - return 0; +out: + return new_ns; +} + +int copy_namespace(int flags, struct task_struct *tsk) +{ + struct namespace *namespace = tsk->namespace; + struct namespace *new_ns; + int err = 0; + + if (!namespace) + return 0; + + get_namespace(namespace); + + if (!(flags & CLONE_NEWNS)) + return 0; + + if (!capable(CAP_SYS_ADMIN)) { + err = -EPERM; + goto out; + } + + new_ns = dup_namespace(tsk, tsk->fs); + if (!new_ns) { + err = -ENOMEM; + goto out; + } + + tsk->namespace = new_ns; out: put_namespace(namespace); - return -ENOMEM; + return err; } asmlinkage long sys_mount(char __user * dev_name, char __user * dir_name, diff --git a/include/linux/namespace.h b/include/linux/namespace.h index 6731977c4c13..3abc8e3b4879 100644 --- a/include/linux/namespace.h +++ b/include/linux/namespace.h @@ -15,6 +15,7 @@ struct namespace { extern int copy_namespace(int, struct task_struct *); extern void __put_namespace(struct namespace *namespace); +extern struct namespace *dup_namespace(struct task_struct *, struct fs_struct *); static inline void put_namespace(struct namespace *namespace) { diff --git a/kernel/fork.c b/kernel/fork.c index 598e5c27242c..07dd241aa1e0 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1388,16 +1388,21 @@ static int unshare_fs(unsigned long unshare_flags, struct fs_struct **new_fsp) } /* - * Unsharing of namespace for tasks created without CLONE_NEWNS is not - * supported yet + * Unshare the namespace structure if it is being shared */ -static int unshare_namespace(unsigned long unshare_flags, struct namespace **new_nsp) +static int unshare_namespace(unsigned long unshare_flags, struct namespace **new_nsp, struct fs_struct *new_fs) { struct namespace *ns = current->namespace; if ((unshare_flags & CLONE_NEWNS) && - (ns && atomic_read(&ns->count) > 1)) - return -EINVAL; + (ns && atomic_read(&ns->count) > 1)) { + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + *new_nsp = dup_namespace(current, new_fs ? new_fs : current->fs); + if (!*new_nsp) + return -ENOMEM; + } return 0; } @@ -1482,7 +1487,7 @@ asmlinkage long sys_unshare(unsigned long unshare_flags) goto bad_unshare_out; if ((err = unshare_fs(unshare_flags, &new_fs))) goto bad_unshare_cleanup_thread; - if ((err = unshare_namespace(unshare_flags, &new_ns))) + if ((err = unshare_namespace(unshare_flags, &new_ns, new_fs))) goto bad_unshare_cleanup_fs; if ((err = unshare_sighand(unshare_flags, &new_sigh))) goto bad_unshare_cleanup_ns; -- cgit v1.3-6-gb490 From a0a7ec308f1be5957b20a1a535d21f683dfd83f0 Mon Sep 17 00:00:00 2001 From: JANAK DESAI Date: Tue, 7 Feb 2006 12:59:01 -0800 Subject: [PATCH] unshare system call -v5: unshare vm If vm structure is being shared, allocate a new one and copy information from the current, shared, structure. Signed-off-by: Janak Desai Cc: Al Viro Cc: Christoph Hellwig Cc: Michael Kerrisk Cc: Andi Kleen Cc: Paul Mackerras Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/fork.c | 87 ++++++++++++++++++++++++++++++++++++++--------------------- 1 file changed, 56 insertions(+), 31 deletions(-) (limited to 'kernel') diff --git a/kernel/fork.c b/kernel/fork.c index 07dd241aa1e0..d1aceaea3f33 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -446,6 +446,55 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm) } } +/* + * Allocate a new mm structure and copy contents from the + * mm structure of the passed in task structure. + */ +static struct mm_struct *dup_mm(struct task_struct *tsk) +{ + struct mm_struct *mm, *oldmm = current->mm; + int err; + + if (!oldmm) + return NULL; + + mm = allocate_mm(); + if (!mm) + goto fail_nomem; + + memcpy(mm, oldmm, sizeof(*mm)); + + if (!mm_init(mm)) + goto fail_nomem; + + if (init_new_context(tsk, mm)) + goto fail_nocontext; + + err = dup_mmap(mm, oldmm); + if (err) + goto free_pt; + + mm->hiwater_rss = get_mm_rss(mm); + mm->hiwater_vm = mm->total_vm; + + return mm; + +free_pt: + mmput(mm); + +fail_nomem: + return NULL; + +fail_nocontext: + /* + * If init_new_context() failed, we cannot use mmput() to free the mm + * because it calls destroy_context() + */ + mm_free_pgd(mm); + free_mm(mm); + return NULL; +} + static int copy_mm(unsigned long clone_flags, struct task_struct * tsk) { struct mm_struct * mm, *oldmm; @@ -473,43 +522,17 @@ static int copy_mm(unsigned long clone_flags, struct task_struct * tsk) } retval = -ENOMEM; - mm = allocate_mm(); + mm = dup_mm(tsk); if (!mm) goto fail_nomem; - /* Copy the current MM stuff.. */ - memcpy(mm, oldmm, sizeof(*mm)); - if (!mm_init(mm)) - goto fail_nomem; - - if (init_new_context(tsk,mm)) - goto fail_nocontext; - - retval = dup_mmap(mm, oldmm); - if (retval) - goto free_pt; - - mm->hiwater_rss = get_mm_rss(mm); - mm->hiwater_vm = mm->total_vm; - good_mm: tsk->mm = mm; tsk->active_mm = mm; return 0; -free_pt: - mmput(mm); fail_nomem: return retval; - -fail_nocontext: - /* - * If init_new_context() failed, we cannot use mmput() to free the mm - * because it calls destroy_context() - */ - mm_free_pgd(mm); - free_mm(mm); - return retval; } static inline struct fs_struct *__copy_fs_struct(struct fs_struct *old) @@ -1423,18 +1446,20 @@ static int unshare_sighand(unsigned long unshare_flags, struct sighand_struct ** } /* - * Unsharing of vm for tasks created with CLONE_VM is not supported yet + * Unshare vm if it is being shared */ static int unshare_vm(unsigned long unshare_flags, struct mm_struct **new_mmp) { struct mm_struct *mm = current->mm; if ((unshare_flags & CLONE_VM) && - (mm && atomic_read(&mm->mm_users) > 1)) - return -EINVAL; + (mm && atomic_read(&mm->mm_users) > 1)) { + *new_mmp = dup_mm(current); + if (!*new_mmp) + return -ENOMEM; + } return 0; - } /* -- cgit v1.3-6-gb490 From a016f3389c06606dd80e687942ff3c71d41823c4 Mon Sep 17 00:00:00 2001 From: JANAK DESAI Date: Tue, 7 Feb 2006 12:59:02 -0800 Subject: [PATCH] unshare system call -v5: unshare files If the file descriptor structure is being shared, allocate a new one and copy information from the current, shared, structure. Signed-off-by: Janak Desai Cc: Al Viro Cc: Christoph Hellwig Cc: Michael Kerrisk Cc: Andi Kleen Cc: Paul Mackerras Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/fork.c | 81 +++++++++++++++++++++++++++++++++++++---------------------- 1 file changed, 51 insertions(+), 30 deletions(-) (limited to 'kernel') diff --git a/kernel/fork.c b/kernel/fork.c index d1aceaea3f33..8e88b374cee9 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -620,32 +620,17 @@ out: return newf; } -static int copy_files(unsigned long clone_flags, struct task_struct * tsk) +/* + * Allocate a new files structure and copy contents from the + * passed in files structure. + */ +static struct files_struct *dup_fd(struct files_struct *oldf, int *errorp) { - struct files_struct *oldf, *newf; + struct files_struct *newf; struct file **old_fds, **new_fds; - int open_files, size, i, error = 0, expand; + int open_files, size, i, expand; struct fdtable *old_fdt, *new_fdt; - /* - * A background process may not have any files ... - */ - oldf = current->files; - if (!oldf) - goto out; - - if (clone_flags & CLONE_FILES) { - atomic_inc(&oldf->count); - goto out; - } - - /* - * Note: we may be using current for both targets (See exec.c) - * This works because we cache current->files (old) as oldf. Don't - * break this. - */ - tsk->files = NULL; - error = -ENOMEM; newf = alloc_files(); if (!newf) goto out; @@ -674,9 +659,9 @@ static int copy_files(unsigned long clone_flags, struct task_struct * tsk) if (expand) { spin_unlock(&oldf->file_lock); spin_lock(&newf->file_lock); - error = expand_files(newf, open_files-1); + *errorp = expand_files(newf, open_files-1); spin_unlock(&newf->file_lock); - if (error < 0) + if (*errorp < 0) goto out_release; new_fdt = files_fdtable(newf); /* @@ -725,10 +710,8 @@ static int copy_files(unsigned long clone_flags, struct task_struct * tsk) memset(&new_fdt->close_on_exec->fds_bits[start], 0, left); } - tsk->files = newf; - error = 0; out: - return error; + return newf; out_release: free_fdset (new_fdt->close_on_exec, new_fdt->max_fdset); @@ -738,6 +721,40 @@ out_release: goto out; } +static int copy_files(unsigned long clone_flags, struct task_struct * tsk) +{ + struct files_struct *oldf, *newf; + int error = 0; + + /* + * A background process may not have any files ... + */ + oldf = current->files; + if (!oldf) + goto out; + + if (clone_flags & CLONE_FILES) { + atomic_inc(&oldf->count); + goto out; + } + + /* + * Note: we may be using current for both targets (See exec.c) + * This works because we cache current->files (old) as oldf. Don't + * break this. + */ + tsk->files = NULL; + error = -ENOMEM; + newf = dup_fd(oldf, &error); + if (!newf) + goto out; + + tsk->files = newf; + error = 0; +out: + return error; +} + /* * Helper to unshare the files of the current task. * We don't want to expose copy_files internals to @@ -1463,15 +1480,19 @@ static int unshare_vm(unsigned long unshare_flags, struct mm_struct **new_mmp) } /* - * Unsharing of files for tasks created with CLONE_FILES is not supported yet + * Unshare file descriptor table if it is being shared */ static int unshare_fd(unsigned long unshare_flags, struct files_struct **new_fdp) { struct files_struct *fd = current->files; + int error = 0; if ((unshare_flags & CLONE_FILES) && - (fd && atomic_read(&fd->count) > 1)) - return -EINVAL; + (fd && atomic_read(&fd->count) > 1)) { + *new_fdp = dup_fd(fd, &error); + if (!*new_fdp) + return error; + } return 0; } -- cgit v1.3-6-gb490 From 1b8623545b42c03eb92e51b28c84acf4b8ba00a3 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 15 Dec 2005 01:07:03 -0500 Subject: [PATCH] remove bogus asm/bug.h includes. A bunch of asm/bug.h includes are both not needed (since it will get pulled anyway) and bogus (since they are done too early). Removed. Signed-off-by: Al Viro --- crypto/scatterwalk.c | 1 - drivers/cdrom/viocd.c | 2 -- drivers/net/hamradio/baycom_par.c | 1 - drivers/tc/tc.c | 1 - drivers/video/backlight/backlight.c | 1 - drivers/video/backlight/lcd.c | 1 - drivers/video/pmag-ba-fb.c | 1 - drivers/video/pmagb-b-fb.c | 1 - fs/reiserfs/hashes.c | 1 - include/asm-mips/io.h | 1 - include/asm-powerpc/dma-mapping.h | 1 - include/linux/cpumask.h | 1 - include/linux/dcache.h | 1 - include/linux/jbd.h | 1 - include/linux/mtd/map.h | 1 - include/linux/nodemask.h | 1 - include/linux/smp.h | 1 - kernel/compat.c | 1 - net/dccp/ccids/lib/tfrc_equation.c | 1 - net/ipv4/xfrm4_policy.c | 1 - net/ipv6/raw.c | 1 - net/ipv6/xfrm6_policy.c | 1 - net/xfrm/xfrm_policy.c | 1 - 23 files changed, 24 deletions(-) (limited to 'kernel') diff --git a/crypto/scatterwalk.c b/crypto/scatterwalk.c index 47ac90e615f4..2953e2cc56f0 100644 --- a/crypto/scatterwalk.c +++ b/crypto/scatterwalk.c @@ -17,7 +17,6 @@ #include #include #include -#include #include #include "internal.h" #include "scatterwalk.h" diff --git a/drivers/cdrom/viocd.c b/drivers/cdrom/viocd.c index 193446e6a08a..e27617259552 100644 --- a/drivers/cdrom/viocd.c +++ b/drivers/cdrom/viocd.c @@ -42,8 +42,6 @@ #include #include -#include - #include #include #include diff --git a/drivers/net/hamradio/baycom_par.c b/drivers/net/hamradio/baycom_par.c index 3b1bef1ee215..77411a00d1ee 100644 --- a/drivers/net/hamradio/baycom_par.c +++ b/drivers/net/hamradio/baycom_par.c @@ -86,7 +86,6 @@ #include #include -#include #include #include diff --git a/drivers/tc/tc.c b/drivers/tc/tc.c index a0e5af638e0e..4a51e56f85b6 100644 --- a/drivers/tc/tc.c +++ b/drivers/tc/tc.c @@ -17,7 +17,6 @@ #include #include -#include #include #include #include diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c index 9d5015e99372..bd39bbd88d41 100644 --- a/drivers/video/backlight/backlight.c +++ b/drivers/video/backlight/backlight.c @@ -13,7 +13,6 @@ #include #include #include -#include static ssize_t backlight_show_power(struct class_device *cdev, char *buf) { diff --git a/drivers/video/backlight/lcd.c b/drivers/video/backlight/lcd.c index 68c690605aa7..9e32485ee7bb 100644 --- a/drivers/video/backlight/lcd.c +++ b/drivers/video/backlight/lcd.c @@ -13,7 +13,6 @@ #include #include #include -#include static ssize_t lcd_show_power(struct class_device *cdev, char *buf) { diff --git a/drivers/video/pmag-ba-fb.c b/drivers/video/pmag-ba-fb.c index f3927b6cda9d..f5361cd8ccce 100644 --- a/drivers/video/pmag-ba-fb.c +++ b/drivers/video/pmag-ba-fb.c @@ -30,7 +30,6 @@ #include #include -#include #include #include diff --git a/drivers/video/pmagb-b-fb.c b/drivers/video/pmagb-b-fb.c index 25148de5fe67..eeeac924b500 100644 --- a/drivers/video/pmagb-b-fb.c +++ b/drivers/video/pmagb-b-fb.c @@ -27,7 +27,6 @@ #include #include -#include #include #include diff --git a/fs/reiserfs/hashes.c b/fs/reiserfs/hashes.c index a3ec238fd9e0..e664ac16fad9 100644 --- a/fs/reiserfs/hashes.c +++ b/fs/reiserfs/hashes.c @@ -21,7 +21,6 @@ #include #include #include -#include #define DELTA 0x9E3779B9 #define FULLROUNDS 10 /* 32 is overkill, 16 is strong crypto */ diff --git a/include/asm-mips/io.h b/include/asm-mips/io.h index d42685747e7d..a9fa1254894a 100644 --- a/include/asm-mips/io.h +++ b/include/asm-mips/io.h @@ -18,7 +18,6 @@ #include #include -#include #include #include #include diff --git a/include/asm-powerpc/dma-mapping.h b/include/asm-powerpc/dma-mapping.h index 837756ab7dc7..2ac63f569592 100644 --- a/include/asm-powerpc/dma-mapping.h +++ b/include/asm-powerpc/dma-mapping.h @@ -15,7 +15,6 @@ #include #include #include -#include #define DMA_ERROR_CODE (~(dma_addr_t)0x0) diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index 13e9f4a3ab26..20b446f26ecd 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -84,7 +84,6 @@ #include #include #include -#include typedef struct { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t; extern cpumask_t _unused_cpumask_arg_; diff --git a/include/linux/dcache.h b/include/linux/dcache.h index a3f09947940e..4361f3789975 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -8,7 +8,6 @@ #include #include #include -#include struct nameidata; struct vfsmount; diff --git a/include/linux/jbd.h b/include/linux/jbd.h index 751bb3849467..0fe4aa891ddc 100644 --- a/include/linux/jbd.h +++ b/include/linux/jbd.h @@ -239,7 +239,6 @@ typedef struct journal_superblock_s #include #include -#include #define JBD_ASSERTIONS #ifdef JBD_ASSERTIONS diff --git a/include/linux/mtd/map.h b/include/linux/mtd/map.h index fedfbc8a287f..7dfd6e1fcde7 100644 --- a/include/linux/mtd/map.h +++ b/include/linux/mtd/map.h @@ -15,7 +15,6 @@ #include #include #include -#include #ifdef CONFIG_MTD_MAP_BANK_WIDTH_1 #define map_bankwidth(map) 1 diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h index 4726ef7ba8e8..b959a4525cbd 100644 --- a/include/linux/nodemask.h +++ b/include/linux/nodemask.h @@ -84,7 +84,6 @@ #include #include #include -#include typedef struct { DECLARE_BITMAP(bits, MAX_NUMNODES); } nodemask_t; extern nodemask_t _unused_nodemask_arg_; diff --git a/include/linux/smp.h b/include/linux/smp.h index 9dfa3ee769ae..44153fdf73fc 100644 --- a/include/linux/smp.h +++ b/include/linux/smp.h @@ -17,7 +17,6 @@ extern void cpu_idle(void); #include #include #include -#include /* * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc. diff --git a/kernel/compat.c b/kernel/compat.c index 1867290c37e3..8c9cd88b6785 100644 --- a/kernel/compat.c +++ b/kernel/compat.c @@ -23,7 +23,6 @@ #include #include -#include int get_compat_timespec(struct timespec *ts, const struct compat_timespec __user *cts) { diff --git a/net/dccp/ccids/lib/tfrc_equation.c b/net/dccp/ccids/lib/tfrc_equation.c index d2b5933b4510..add3cae65e2d 100644 --- a/net/dccp/ccids/lib/tfrc_equation.c +++ b/net/dccp/ccids/lib/tfrc_equation.c @@ -15,7 +15,6 @@ #include #include -#include #include #include "tfrc.h" diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c index 42196ba3b0b9..45f7ae58f2c0 100644 --- a/net/ipv4/xfrm4_policy.c +++ b/net/ipv4/xfrm4_policy.c @@ -8,7 +8,6 @@ * */ -#include #include #include #include diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c index 66f1d12ea578..738376cf0c51 100644 --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -35,7 +35,6 @@ #include #include #include -#include #include #include diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c index 69bd957380e7..91cce8b2d7a5 100644 --- a/net/ipv6/xfrm6_policy.c +++ b/net/ipv6/xfrm6_policy.c @@ -11,7 +11,6 @@ * */ -#include #include #include #include diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index 077bbf9fb9b7..dbf4620768d6 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -13,7 +13,6 @@ * */ -#include #include #include #include -- cgit v1.3-6-gb490 From 53f087febfd12e74ba9f1082e71e9a45adc039ad Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 1 Feb 2006 05:56:41 -0500 Subject: [PATCH] timer.c NULL noise removal Signed-off-by: Al Viro --- kernel/timer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/timer.c b/kernel/timer.c index 4f1cb0ab5251..b9dad3994676 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -495,7 +495,7 @@ unsigned long next_timer_interrupt(void) base = &__get_cpu_var(tvec_bases); spin_lock(&base->t_base.lock); expires = base->timer_jiffies + (LONG_MAX >> 1); - list = 0; + list = NULL; /* Look for timer events in tv1. */ j = base->timer_jiffies & TVR_MASK; -- cgit v1.3-6-gb490 From 4bb8089c86b95b4f6bbd839cb83ca4556b06a031 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 1 Feb 2006 05:57:32 -0500 Subject: [PATCH] kernel/sys.c NULL noise removal Signed-off-by: Al Viro --- kernel/sys.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/sys.c b/kernel/sys.c index 0929c698affc..f91218a5463e 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -428,7 +428,7 @@ void kernel_kexec(void) { #ifdef CONFIG_KEXEC struct kimage *image; - image = xchg(&kexec_image, 0); + image = xchg(&kexec_image, NULL); if (!image) { return; } -- cgit v1.3-6-gb490