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path: root/fs/quota/quota.c
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Diffstat (limited to 'fs/quota/quota.c')
-rw-r--r--fs/quota/quota.c162
1 files changed, 128 insertions, 34 deletions
diff --git a/fs/quota/quota.c b/fs/quota/quota.c
index b299961e1ed..ff3f0b3cfdb 100644
--- a/fs/quota/quota.c
+++ b/fs/quota/quota.c
@@ -9,11 +9,10 @@
#include <linux/namei.h>
#include <linux/slab.h>
#include <asm/current.h>
-#include <asm/uaccess.h>
+#include <linux/uaccess.h>
#include <linux/kernel.h>
#include <linux/security.h>
#include <linux/syscalls.h>
-#include <linux/buffer_head.h>
#include <linux/capability.h>
#include <linux/quotaops.h>
#include <linux/types.h>
@@ -28,13 +27,14 @@ static int check_quotactl_permission(struct super_block *sb, int type, int cmd,
case Q_SYNC:
case Q_GETINFO:
case Q_XGETQSTAT:
+ case Q_XGETQSTATV:
case Q_XQUOTASYNC:
break;
/* allow to query information for dquots we "own" */
case Q_GETQUOTA:
case Q_XGETQUOTA:
- if ((type == USRQUOTA && current_euid() == id) ||
- (type == GRPQUOTA && in_egroup_p(id)))
+ if ((type == USRQUOTA && uid_eq(current_euid(), make_kuid(current_user_ns(), id))) ||
+ (type == GRPQUOTA && in_egroup_p(make_kgid(current_user_ns(), id))))
break;
/*FALLTHROUGH*/
default:
@@ -48,7 +48,7 @@ static int check_quotactl_permission(struct super_block *sb, int type, int cmd,
static void quota_sync_one(struct super_block *sb, void *arg)
{
if (sb->s_qcop && sb->s_qcop->quota_sync)
- sb->s_qcop->quota_sync(sb, *(int *)arg, 1);
+ sb->s_qcop->quota_sync(sb, *(int *)arg);
}
static int quota_sync_all(int type)
@@ -64,18 +64,15 @@ static int quota_sync_all(int type)
}
static int quota_quotaon(struct super_block *sb, int type, int cmd, qid_t id,
- void __user *addr)
+ struct path *path)
{
- char *pathname;
- int ret = -ENOSYS;
-
- pathname = getname(addr);
- if (IS_ERR(pathname))
- return PTR_ERR(pathname);
- if (sb->s_qcop->quota_on)
- ret = sb->s_qcop->quota_on(sb, type, id, pathname);
- putname(pathname);
- return ret;
+ if (!sb->s_qcop->quota_on && !sb->s_qcop->quota_on_meta)
+ return -ENOSYS;
+ if (sb->s_qcop->quota_on_meta)
+ return sb->s_qcop->quota_on_meta(sb, type, id);
+ if (IS_ERR(path))
+ return PTR_ERR(path);
+ return sb->s_qcop->quota_on(sb, type, id, path);
}
static int quota_getfmt(struct super_block *sb, int type, void __user *addr)
@@ -120,6 +117,7 @@ static int quota_setinfo(struct super_block *sb, int type, void __user *addr)
static void copy_to_if_dqblk(struct if_dqblk *dst, struct fs_disk_quota *src)
{
+ memset(dst, 0, sizeof(*dst));
dst->dqb_bhardlimit = src->d_blk_hardlimit;
dst->dqb_bsoftlimit = src->d_blk_softlimit;
dst->dqb_curspace = src->d_bcount;
@@ -134,13 +132,17 @@ static void copy_to_if_dqblk(struct if_dqblk *dst, struct fs_disk_quota *src)
static int quota_getquota(struct super_block *sb, int type, qid_t id,
void __user *addr)
{
+ struct kqid qid;
struct fs_disk_quota fdq;
struct if_dqblk idq;
int ret;
if (!sb->s_qcop->get_dqblk)
return -ENOSYS;
- ret = sb->s_qcop->get_dqblk(sb, type, id, &fdq);
+ qid = make_kqid(current_user_ns(), type, id);
+ if (!qid_valid(qid))
+ return -EINVAL;
+ ret = sb->s_qcop->get_dqblk(sb, qid, &fdq);
if (ret)
return ret;
copy_to_if_dqblk(&idq, &fdq);
@@ -180,13 +182,17 @@ static int quota_setquota(struct super_block *sb, int type, qid_t id,
{
struct fs_disk_quota fdq;
struct if_dqblk idq;
+ struct kqid qid;
if (copy_from_user(&idq, addr, sizeof(idq)))
return -EFAULT;
if (!sb->s_qcop->set_dqblk)
return -ENOSYS;
+ qid = make_kqid(current_user_ns(), type, id);
+ if (!qid_valid(qid))
+ return -EINVAL;
copy_from_if_dqblk(&fdq, &idq);
- return sb->s_qcop->set_dqblk(sb, type, id, &fdq);
+ return sb->s_qcop->set_dqblk(sb, qid, &fdq);
}
static int quota_setxstate(struct super_block *sb, int cmd, void __user *addr)
@@ -213,35 +219,79 @@ static int quota_getxstate(struct super_block *sb, void __user *addr)
return ret;
}
+static int quota_getxstatev(struct super_block *sb, void __user *addr)
+{
+ struct fs_quota_statv fqs;
+ int ret;
+
+ if (!sb->s_qcop->get_xstatev)
+ return -ENOSYS;
+
+ memset(&fqs, 0, sizeof(fqs));
+ if (copy_from_user(&fqs, addr, 1)) /* Just read qs_version */
+ return -EFAULT;
+
+ /* If this kernel doesn't support user specified version, fail */
+ switch (fqs.qs_version) {
+ case FS_QSTATV_VERSION1:
+ break;
+ default:
+ return -EINVAL;
+ }
+ ret = sb->s_qcop->get_xstatev(sb, &fqs);
+ if (!ret && copy_to_user(addr, &fqs, sizeof(fqs)))
+ return -EFAULT;
+ return ret;
+}
+
static int quota_setxquota(struct super_block *sb, int type, qid_t id,
void __user *addr)
{
struct fs_disk_quota fdq;
+ struct kqid qid;
if (copy_from_user(&fdq, addr, sizeof(fdq)))
return -EFAULT;
if (!sb->s_qcop->set_dqblk)
return -ENOSYS;
- return sb->s_qcop->set_dqblk(sb, type, id, &fdq);
+ qid = make_kqid(current_user_ns(), type, id);
+ if (!qid_valid(qid))
+ return -EINVAL;
+ return sb->s_qcop->set_dqblk(sb, qid, &fdq);
}
static int quota_getxquota(struct super_block *sb, int type, qid_t id,
void __user *addr)
{
struct fs_disk_quota fdq;
+ struct kqid qid;
int ret;
if (!sb->s_qcop->get_dqblk)
return -ENOSYS;
- ret = sb->s_qcop->get_dqblk(sb, type, id, &fdq);
+ qid = make_kqid(current_user_ns(), type, id);
+ if (!qid_valid(qid))
+ return -EINVAL;
+ ret = sb->s_qcop->get_dqblk(sb, qid, &fdq);
if (!ret && copy_to_user(addr, &fdq, sizeof(fdq)))
return -EFAULT;
return ret;
}
+static int quota_rmxquota(struct super_block *sb, void __user *addr)
+{
+ __u32 flags;
+
+ if (copy_from_user(&flags, addr, sizeof(flags)))
+ return -EFAULT;
+ if (!sb->s_qcop->rm_xquota)
+ return -ENOSYS;
+ return sb->s_qcop->rm_xquota(sb, flags);
+}
+
/* Copy parameters and call proper function */
static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
- void __user *addr)
+ void __user *addr, struct path *path)
{
int ret;
@@ -256,7 +306,7 @@ static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
switch (cmd) {
case Q_QUOTAON:
- return quota_quotaon(sb, type, cmd, id, addr);
+ return quota_quotaon(sb, type, cmd, id, path);
case Q_QUOTAOFF:
if (!sb->s_qcop->quota_off)
return -ENOSYS;
@@ -274,46 +324,71 @@ static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
case Q_SYNC:
if (!sb->s_qcop->quota_sync)
return -ENOSYS;
- return sb->s_qcop->quota_sync(sb, type, 1);
+ return sb->s_qcop->quota_sync(sb, type);
case Q_XQUOTAON:
case Q_XQUOTAOFF:
- case Q_XQUOTARM:
return quota_setxstate(sb, cmd, addr);
+ case Q_XQUOTARM:
+ return quota_rmxquota(sb, addr);
case Q_XGETQSTAT:
return quota_getxstate(sb, addr);
+ case Q_XGETQSTATV:
+ return quota_getxstatev(sb, addr);
case Q_XSETQLIM:
return quota_setxquota(sb, type, id, addr);
case Q_XGETQUOTA:
return quota_getxquota(sb, type, id, addr);
case Q_XQUOTASYNC:
- /* caller already holds s_umount */
if (sb->s_flags & MS_RDONLY)
return -EROFS;
- writeback_inodes_sb(sb);
+ /* XFS quotas are fully coherent now, making this call a noop */
return 0;
default:
return -EINVAL;
}
}
+#ifdef CONFIG_BLOCK
+
+/* Return 1 if 'cmd' will block on frozen filesystem */
+static int quotactl_cmd_write(int cmd)
+{
+ switch (cmd) {
+ case Q_GETFMT:
+ case Q_GETINFO:
+ case Q_SYNC:
+ case Q_XGETQSTAT:
+ case Q_XGETQSTATV:
+ case Q_XGETQUOTA:
+ case Q_XQUOTASYNC:
+ return 0;
+ }
+ return 1;
+}
+
+#endif /* CONFIG_BLOCK */
+
/*
* look up a superblock on which quota ops will be performed
* - use the name of a block device to find the superblock thereon
*/
-static struct super_block *quotactl_block(const char __user *special)
+static struct super_block *quotactl_block(const char __user *special, int cmd)
{
#ifdef CONFIG_BLOCK
struct block_device *bdev;
struct super_block *sb;
- char *tmp = getname(special);
+ struct filename *tmp = getname(special);
if (IS_ERR(tmp))
return ERR_CAST(tmp);
- bdev = lookup_bdev(tmp);
+ bdev = lookup_bdev(tmp->name);
putname(tmp);
if (IS_ERR(bdev))
return ERR_CAST(bdev);
- sb = get_super(bdev);
+ if (quotactl_cmd_write(cmd))
+ sb = get_super_thawed(bdev);
+ else
+ sb = get_super(bdev);
bdput(bdev);
if (!sb)
return ERR_PTR(-ENODEV);
@@ -335,6 +410,7 @@ SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special,
{
uint cmds, type;
struct super_block *sb = NULL;
+ struct path path, *pathp = NULL;
int ret;
cmds = cmd >> SUBCMDSHIFT;
@@ -351,12 +427,30 @@ SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special,
return -ENODEV;
}
- sb = quotactl_block(special);
- if (IS_ERR(sb))
- return PTR_ERR(sb);
+ /*
+ * Path for quotaon has to be resolved before grabbing superblock
+ * because that gets s_umount sem which is also possibly needed by path
+ * resolution (think about autofs) and thus deadlocks could arise.
+ */
+ if (cmds == Q_QUOTAON) {
+ ret = user_path_at(AT_FDCWD, addr, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &path);
+ if (ret)
+ pathp = ERR_PTR(ret);
+ else
+ pathp = &path;
+ }
+
+ sb = quotactl_block(special, cmds);
+ if (IS_ERR(sb)) {
+ ret = PTR_ERR(sb);
+ goto out;
+ }
- ret = do_quotactl(sb, type, cmds, id, addr);
+ ret = do_quotactl(sb, type, cmds, id, addr, pathp);
drop_super(sb);
+out:
+ if (pathp && !IS_ERR(pathp))
+ path_put(pathp);
return ret;
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-04 20:15:26 +0000