diff options
| -rw-r--r-- | fs/quota/dquot.c | 11 | ||||
| -rw-r--r-- | fs/quota/quota.c | 16 |
2 files changed, 24 insertions, 3 deletions
diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c index 1bfac28b7e7d..047afb966420 100644 --- a/fs/quota/dquot.c +++ b/fs/quota/dquot.c @@ -2107,6 +2107,10 @@ int dquot_disable(struct super_block *sb, int type, unsigned int flags) struct quota_info *dqopt = sb_dqopt(sb); struct inode *toputinode[MAXQUOTAS]; + /* s_umount should be held in exclusive mode */ + if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount))) + up_read(&sb->s_umount); + /* Cannot turn off usage accounting without turning off limits, or * suspend quotas and simultaneously turn quotas off. */ if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED)) @@ -2371,6 +2375,10 @@ int dquot_resume(struct super_block *sb, int type) int ret = 0, cnt; unsigned int flags; + /* s_umount should be held in exclusive mode */ + if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount))) + up_read(&sb->s_umount); + for (cnt = 0; cnt < MAXQUOTAS; cnt++) { if (type != -1 && cnt != type) continue; @@ -2430,6 +2438,9 @@ int dquot_enable(struct inode *inode, int type, int format_id, /* Just unsuspend quotas? */ BUG_ON(flags & DQUOT_SUSPENDED); + /* s_umount should be held in exclusive mode */ + if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount))) + up_read(&sb->s_umount); if (!flags) return 0; diff --git a/fs/quota/quota.c b/fs/quota/quota.c index 2d445425aad7..6ce6f4b6826b 100644 --- a/fs/quota/quota.c +++ b/fs/quota/quota.c @@ -789,9 +789,14 @@ static int quotactl_cmd_write(int cmd) } return 1; } - #endif /* CONFIG_BLOCK */ +/* Return true if quotactl command is manipulating quota on/off state */ +static bool quotactl_cmd_onoff(int cmd) +{ + return (cmd == Q_QUOTAON) || (cmd == Q_QUOTAOFF); +} + /* * look up a superblock on which quota ops will be performed * - use the name of a block device to find the superblock thereon @@ -809,7 +814,9 @@ static struct super_block *quotactl_block(const char __user *special, int cmd) putname(tmp); if (IS_ERR(bdev)) return ERR_CAST(bdev); - if (quotactl_cmd_write(cmd)) + if (quotactl_cmd_onoff(cmd)) + sb = get_super_exclusive_thawed(bdev); + else if (quotactl_cmd_write(cmd)) sb = get_super_thawed(bdev); else sb = get_super(bdev); @@ -872,7 +879,10 @@ SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special, ret = do_quotactl(sb, type, cmds, id, addr, pathp); - drop_super(sb); + if (!quotactl_cmd_onoff(cmds)) + drop_super(sb); + else + drop_super_exclusive(sb); out: if (pathp && !IS_ERR(pathp)) path_put(pathp); |