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author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-22 12:34:08 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-22 12:34:08 -0700 |
commit | cd9b44f90763c3367e8dd0601849ffb028e8ba52 (patch) | |
tree | d1da0c2d49e3622fe51584a154ab383b3e783c1b /fs/autofs | |
parent | df2def49c57b4146520a1f4ca37bc3f494e2cd67 (diff) | |
parent | 2a9d6481004215da8e93edb588cf448f2af80303 (diff) | |
download | lwn-cd9b44f90763c3367e8dd0601849ffb028e8ba52.tar.gz lwn-cd9b44f90763c3367e8dd0601849ffb028e8ba52.zip |
Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:
- the rest of MM
- procfs updates
- various misc things
- more y2038 fixes
- get_maintainer updates
- lib/ updates
- checkpatch updates
- various epoll updates
- autofs updates
- hfsplus
- some reiserfs work
- fatfs updates
- signal.c cleanups
- ipc/ updates
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (166 commits)
ipc/util.c: update return value of ipc_getref from int to bool
ipc/util.c: further variable name cleanups
ipc: simplify ipc initialization
ipc: get rid of ids->tables_initialized hack
lib/rhashtable: guarantee initial hashtable allocation
lib/rhashtable: simplify bucket_table_alloc()
ipc: drop ipc_lock()
ipc/util.c: correct comment in ipc_obtain_object_check
ipc: rename ipcctl_pre_down_nolock()
ipc/util.c: use ipc_rcu_putref() for failues in ipc_addid()
ipc: reorganize initialization of kern_ipc_perm.seq
ipc: compute kern_ipc_perm.id under the ipc lock
init/Kconfig: remove EXPERT from CHECKPOINT_RESTORE
fs/sysv/inode.c: use ktime_get_real_seconds() for superblock stamp
adfs: use timespec64 for time conversion
kernel/sysctl.c: fix typos in comments
drivers/rapidio/devices/rio_mport_cdev.c: remove redundant pointer md
fork: don't copy inconsistent signal handler state to child
signal: make get_signal() return bool
signal: make sigkill_pending() return bool
...
Diffstat (limited to 'fs/autofs')
-rw-r--r-- | fs/autofs/autofs_i.h | 12 | ||||
-rw-r--r-- | fs/autofs/expire.c | 143 | ||||
-rw-r--r-- | fs/autofs/inode.c | 1 | ||||
-rw-r--r-- | fs/autofs/root.c | 33 |
4 files changed, 120 insertions, 69 deletions
diff --git a/fs/autofs/autofs_i.h b/fs/autofs/autofs_i.h index 502812289850..9f9cadbfbd7a 100644 --- a/fs/autofs/autofs_i.h +++ b/fs/autofs/autofs_i.h @@ -27,6 +27,7 @@ #include <linux/list.h> #include <linux/completion.h> #include <linux/file.h> +#include <linux/magic.h> /* This is the range of ioctl() numbers we claim as ours */ #define AUTOFS_IOC_FIRST AUTOFS_IOC_READY @@ -125,7 +126,8 @@ struct autofs_sb_info { static inline struct autofs_sb_info *autofs_sbi(struct super_block *sb) { - return (struct autofs_sb_info *)(sb->s_fs_info); + return sb->s_magic != AUTOFS_SUPER_MAGIC ? + NULL : (struct autofs_sb_info *)(sb->s_fs_info); } static inline struct autofs_info *autofs_dentry_ino(struct dentry *dentry) @@ -152,15 +154,9 @@ int autofs_expire_run(struct super_block *, struct vfsmount *, struct autofs_sb_info *, struct autofs_packet_expire __user *); int autofs_do_expire_multi(struct super_block *sb, struct vfsmount *mnt, - struct autofs_sb_info *sbi, int when); + struct autofs_sb_info *sbi, unsigned int how); int autofs_expire_multi(struct super_block *, struct vfsmount *, struct autofs_sb_info *, int __user *); -struct dentry *autofs_expire_direct(struct super_block *sb, - struct vfsmount *mnt, - struct autofs_sb_info *sbi, int how); -struct dentry *autofs_expire_indirect(struct super_block *sb, - struct vfsmount *mnt, - struct autofs_sb_info *sbi, int how); /* Device node initialization */ diff --git a/fs/autofs/expire.c b/fs/autofs/expire.c index b332d3f6e730..d441244b79df 100644 --- a/fs/autofs/expire.c +++ b/fs/autofs/expire.c @@ -10,11 +10,9 @@ #include "autofs_i.h" -static unsigned long now; - /* Check if a dentry can be expired */ static inline int autofs_can_expire(struct dentry *dentry, - unsigned long timeout, int do_now) + unsigned long timeout, unsigned int how) { struct autofs_info *ino = autofs_dentry_ino(dentry); @@ -22,16 +20,17 @@ static inline int autofs_can_expire(struct dentry *dentry, if (ino == NULL) return 0; - if (!do_now) { + if (!(how & AUTOFS_EXP_IMMEDIATE)) { /* Too young to die */ - if (!timeout || time_after(ino->last_used + timeout, now)) + if (!timeout || time_after(ino->last_used + timeout, jiffies)) return 0; } return 1; } /* Check a mount point for busyness */ -static int autofs_mount_busy(struct vfsmount *mnt, struct dentry *dentry) +static int autofs_mount_busy(struct vfsmount *mnt, + struct dentry *dentry, unsigned int how) { struct dentry *top = dentry; struct path path = {.mnt = mnt, .dentry = dentry}; @@ -52,6 +51,12 @@ static int autofs_mount_busy(struct vfsmount *mnt, struct dentry *dentry) goto done; } + /* Not a submount, has a forced expire been requested */ + if (how & AUTOFS_EXP_FORCED) { + status = 0; + goto done; + } + /* Update the expiry counter if fs is busy */ if (!may_umount_tree(path.mnt)) { struct autofs_info *ino; @@ -187,10 +192,14 @@ again: static int autofs_direct_busy(struct vfsmount *mnt, struct dentry *top, unsigned long timeout, - int do_now) + unsigned int how) { pr_debug("top %p %pd\n", top, top); + /* Forced expire, user space handles busy mounts */ + if (how & AUTOFS_EXP_FORCED) + return 0; + /* If it's busy update the expiry counters */ if (!may_umount_tree(mnt)) { struct autofs_info *ino; @@ -202,7 +211,7 @@ static int autofs_direct_busy(struct vfsmount *mnt, } /* Timeout of a direct mount is determined by its top dentry */ - if (!autofs_can_expire(top, timeout, do_now)) + if (!autofs_can_expire(top, timeout, how)) return 1; return 0; @@ -215,7 +224,7 @@ static int autofs_direct_busy(struct vfsmount *mnt, static int autofs_tree_busy(struct vfsmount *mnt, struct dentry *top, unsigned long timeout, - int do_now) + unsigned int how) { struct autofs_info *top_ino = autofs_dentry_ino(top); struct dentry *p; @@ -237,7 +246,7 @@ static int autofs_tree_busy(struct vfsmount *mnt, * If the fs is busy update the expiry counter. */ if (d_mountpoint(p)) { - if (autofs_mount_busy(mnt, p)) { + if (autofs_mount_busy(mnt, p, how)) { top_ino->last_used = jiffies; dput(p); return 1; @@ -260,8 +269,12 @@ static int autofs_tree_busy(struct vfsmount *mnt, } } + /* Forced expire, user space handles busy mounts */ + if (how & AUTOFS_EXP_FORCED) + return 0; + /* Timeout of a tree mount is ultimately determined by its top dentry */ - if (!autofs_can_expire(top, timeout, do_now)) + if (!autofs_can_expire(top, timeout, how)) return 1; return 0; @@ -270,7 +283,7 @@ static int autofs_tree_busy(struct vfsmount *mnt, static struct dentry *autofs_check_leaves(struct vfsmount *mnt, struct dentry *parent, unsigned long timeout, - int do_now) + unsigned int how) { struct dentry *p; @@ -282,11 +295,17 @@ static struct dentry *autofs_check_leaves(struct vfsmount *mnt, if (d_mountpoint(p)) { /* Can we umount this guy */ - if (autofs_mount_busy(mnt, p)) + if (autofs_mount_busy(mnt, p, how)) continue; + /* This isn't a submount so if a forced expire + * has been requested, user space handles busy + * mounts */ + if (how & AUTOFS_EXP_FORCED) + return p; + /* Can we expire this guy */ - if (autofs_can_expire(p, timeout, do_now)) + if (autofs_can_expire(p, timeout, how)) return p; } } @@ -294,23 +313,21 @@ static struct dentry *autofs_check_leaves(struct vfsmount *mnt, } /* Check if we can expire a direct mount (possibly a tree) */ -struct dentry *autofs_expire_direct(struct super_block *sb, - struct vfsmount *mnt, - struct autofs_sb_info *sbi, - int how) +static struct dentry *autofs_expire_direct(struct super_block *sb, + struct vfsmount *mnt, + struct autofs_sb_info *sbi, + unsigned int how) { - unsigned long timeout; struct dentry *root = dget(sb->s_root); - int do_now = how & AUTOFS_EXP_IMMEDIATE; struct autofs_info *ino; + unsigned long timeout; if (!root) return NULL; - now = jiffies; timeout = sbi->exp_timeout; - if (!autofs_direct_busy(mnt, root, timeout, do_now)) { + if (!autofs_direct_busy(mnt, root, timeout, how)) { spin_lock(&sbi->fs_lock); ino = autofs_dentry_ino(root); /* No point expiring a pending mount */ @@ -321,7 +338,7 @@ struct dentry *autofs_expire_direct(struct super_block *sb, ino->flags |= AUTOFS_INF_WANT_EXPIRE; spin_unlock(&sbi->fs_lock); synchronize_rcu(); - if (!autofs_direct_busy(mnt, root, timeout, do_now)) { + if (!autofs_direct_busy(mnt, root, timeout, how)) { spin_lock(&sbi->fs_lock); ino->flags |= AUTOFS_INF_EXPIRING; init_completion(&ino->expire_complete); @@ -346,10 +363,8 @@ out: static struct dentry *should_expire(struct dentry *dentry, struct vfsmount *mnt, unsigned long timeout, - int how) + unsigned int how) { - int do_now = how & AUTOFS_EXP_IMMEDIATE; - int exp_leaves = how & AUTOFS_EXP_LEAVES; struct autofs_info *ino = autofs_dentry_ino(dentry); unsigned int ino_count; @@ -367,22 +382,33 @@ static struct dentry *should_expire(struct dentry *dentry, pr_debug("checking mountpoint %p %pd\n", dentry, dentry); /* Can we umount this guy */ - if (autofs_mount_busy(mnt, dentry)) + if (autofs_mount_busy(mnt, dentry, how)) return NULL; + /* This isn't a submount so if a forced expire + * has been requested, user space handles busy + * mounts */ + if (how & AUTOFS_EXP_FORCED) + return dentry; + /* Can we expire this guy */ - if (autofs_can_expire(dentry, timeout, do_now)) + if (autofs_can_expire(dentry, timeout, how)) return dentry; return NULL; } if (d_really_is_positive(dentry) && d_is_symlink(dentry)) { pr_debug("checking symlink %p %pd\n", dentry, dentry); + + /* Forced expire, user space handles busy mounts */ + if (how & AUTOFS_EXP_FORCED) + return dentry; + /* * A symlink can't be "busy" in the usual sense so * just check last used for expire timeout. */ - if (autofs_can_expire(dentry, timeout, do_now)) + if (autofs_can_expire(dentry, timeout, how)) return dentry; return NULL; } @@ -391,27 +417,33 @@ static struct dentry *should_expire(struct dentry *dentry, return NULL; /* Case 2: tree mount, expire iff entire tree is not busy */ - if (!exp_leaves) { - /* Path walk currently on this dentry? */ - ino_count = atomic_read(&ino->count) + 1; - if (d_count(dentry) > ino_count) - return NULL; + if (!(how & AUTOFS_EXP_LEAVES)) { + /* Not a forced expire? */ + if (!(how & AUTOFS_EXP_FORCED)) { + /* ref-walk currently on this dentry? */ + ino_count = atomic_read(&ino->count) + 1; + if (d_count(dentry) > ino_count) + return NULL; + } - if (!autofs_tree_busy(mnt, dentry, timeout, do_now)) + if (!autofs_tree_busy(mnt, dentry, timeout, how)) return dentry; /* * Case 3: pseudo direct mount, expire individual leaves * (autofs-4.1). */ } else { - /* Path walk currently on this dentry? */ struct dentry *expired; - ino_count = atomic_read(&ino->count) + 1; - if (d_count(dentry) > ino_count) - return NULL; + /* Not a forced expire? */ + if (!(how & AUTOFS_EXP_FORCED)) { + /* ref-walk currently on this dentry? */ + ino_count = atomic_read(&ino->count) + 1; + if (d_count(dentry) > ino_count) + return NULL; + } - expired = autofs_check_leaves(mnt, dentry, timeout, do_now); + expired = autofs_check_leaves(mnt, dentry, timeout, how); if (expired) { if (expired == dentry) dput(dentry); @@ -427,10 +459,10 @@ static struct dentry *should_expire(struct dentry *dentry, * - it is unused by any user process * - it has been unused for exp_timeout time */ -struct dentry *autofs_expire_indirect(struct super_block *sb, - struct vfsmount *mnt, - struct autofs_sb_info *sbi, - int how) +static struct dentry *autofs_expire_indirect(struct super_block *sb, + struct vfsmount *mnt, + struct autofs_sb_info *sbi, + unsigned int how) { unsigned long timeout; struct dentry *root = sb->s_root; @@ -442,13 +474,10 @@ struct dentry *autofs_expire_indirect(struct super_block *sb, if (!root) return NULL; - now = jiffies; timeout = sbi->exp_timeout; dentry = NULL; while ((dentry = get_next_positive_subdir(dentry, root))) { - int flags = how; - spin_lock(&sbi->fs_lock); ino = autofs_dentry_ino(dentry); if (ino->flags & AUTOFS_INF_WANT_EXPIRE) { @@ -457,7 +486,7 @@ struct dentry *autofs_expire_indirect(struct super_block *sb, } spin_unlock(&sbi->fs_lock); - expired = should_expire(dentry, mnt, timeout, flags); + expired = should_expire(dentry, mnt, timeout, how); if (!expired) continue; @@ -470,7 +499,7 @@ struct dentry *autofs_expire_indirect(struct super_block *sb, /* Make sure a reference is not taken on found if * things have changed. */ - flags &= ~AUTOFS_EXP_LEAVES; + how &= ~AUTOFS_EXP_LEAVES; found = should_expire(expired, mnt, timeout, how); if (!found || found != expired) /* Something has changed, continue */ @@ -575,7 +604,7 @@ int autofs_expire_run(struct super_block *sb, spin_lock(&sbi->fs_lock); ino = autofs_dentry_ino(dentry); /* avoid rapid-fire expire attempts if expiry fails */ - ino->last_used = now; + ino->last_used = jiffies; ino->flags &= ~(AUTOFS_INF_EXPIRING|AUTOFS_INF_WANT_EXPIRE); complete_all(&ino->expire_complete); spin_unlock(&sbi->fs_lock); @@ -584,15 +613,15 @@ int autofs_expire_run(struct super_block *sb, } int autofs_do_expire_multi(struct super_block *sb, struct vfsmount *mnt, - struct autofs_sb_info *sbi, int when) + struct autofs_sb_info *sbi, unsigned int how) { struct dentry *dentry; int ret = -EAGAIN; if (autofs_type_trigger(sbi->type)) - dentry = autofs_expire_direct(sb, mnt, sbi, when); + dentry = autofs_expire_direct(sb, mnt, sbi, how); else - dentry = autofs_expire_indirect(sb, mnt, sbi, when); + dentry = autofs_expire_indirect(sb, mnt, sbi, how); if (dentry) { struct autofs_info *ino = autofs_dentry_ino(dentry); @@ -605,7 +634,7 @@ int autofs_do_expire_multi(struct super_block *sb, struct vfsmount *mnt, spin_lock(&sbi->fs_lock); /* avoid rapid-fire expire attempts if expiry fails */ - ino->last_used = now; + ino->last_used = jiffies; ino->flags &= ~(AUTOFS_INF_EXPIRING|AUTOFS_INF_WANT_EXPIRE); complete_all(&ino->expire_complete); spin_unlock(&sbi->fs_lock); @@ -622,10 +651,10 @@ int autofs_do_expire_multi(struct super_block *sb, struct vfsmount *mnt, int autofs_expire_multi(struct super_block *sb, struct vfsmount *mnt, struct autofs_sb_info *sbi, int __user *arg) { - int do_now = 0; + unsigned int how = 0; - if (arg && get_user(do_now, arg)) + if (arg && get_user(how, arg)) return -EFAULT; - return autofs_do_expire_multi(sb, mnt, sbi, do_now); + return autofs_do_expire_multi(sb, mnt, sbi, how); } diff --git a/fs/autofs/inode.c b/fs/autofs/inode.c index b51980fc274e..846c052569dd 100644 --- a/fs/autofs/inode.c +++ b/fs/autofs/inode.c @@ -10,7 +10,6 @@ #include <linux/seq_file.h> #include <linux/pagemap.h> #include <linux/parser.h> -#include <linux/magic.h> #include "autofs_i.h" diff --git a/fs/autofs/root.c b/fs/autofs/root.c index a3d414150578..782e57b911ab 100644 --- a/fs/autofs/root.c +++ b/fs/autofs/root.c @@ -559,6 +559,13 @@ static int autofs_dir_symlink(struct inode *dir, if (!autofs_oz_mode(sbi)) return -EACCES; + /* autofs_oz_mode() needs to allow path walks when the + * autofs mount is catatonic but the state of an autofs + * file system needs to be preserved over restarts. + */ + if (sbi->catatonic) + return -EACCES; + BUG_ON(!ino); autofs_clean_ino(ino); @@ -612,9 +619,15 @@ static int autofs_dir_unlink(struct inode *dir, struct dentry *dentry) struct autofs_info *ino = autofs_dentry_ino(dentry); struct autofs_info *p_ino; - /* This allows root to remove symlinks */ - if (!autofs_oz_mode(sbi) && !capable(CAP_SYS_ADMIN)) - return -EPERM; + if (!autofs_oz_mode(sbi)) + return -EACCES; + + /* autofs_oz_mode() needs to allow path walks when the + * autofs mount is catatonic but the state of an autofs + * file system needs to be preserved over restarts. + */ + if (sbi->catatonic) + return -EACCES; if (atomic_dec_and_test(&ino->count)) { p_ino = autofs_dentry_ino(dentry->d_parent); @@ -697,6 +710,13 @@ static int autofs_dir_rmdir(struct inode *dir, struct dentry *dentry) if (!autofs_oz_mode(sbi)) return -EACCES; + /* autofs_oz_mode() needs to allow path walks when the + * autofs mount is catatonic but the state of an autofs + * file system needs to be preserved over restarts. + */ + if (sbi->catatonic) + return -EACCES; + spin_lock(&sbi->lookup_lock); if (!simple_empty(dentry)) { spin_unlock(&sbi->lookup_lock); @@ -735,6 +755,13 @@ static int autofs_dir_mkdir(struct inode *dir, if (!autofs_oz_mode(sbi)) return -EACCES; + /* autofs_oz_mode() needs to allow path walks when the + * autofs mount is catatonic but the state of an autofs + * file system needs to be preserved over restarts. + */ + if (sbi->catatonic) + return -EACCES; + pr_debug("dentry %p, creating %pd\n", dentry, dentry); BUG_ON(!ino); |