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-rw-r--r--fs/autofs/autofs_i.h12
-rw-r--r--fs/autofs/expire.c143
-rw-r--r--fs/autofs/inode.c1
-rw-r--r--fs/autofs/root.c33
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);
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-04 21:49:05 +0300