From 80bdad3d7e3ec03f812471d9309f5f682e10f52b Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 17 Sep 2020 09:41:59 +0200 Subject: quota: simplify the quotactl compat handling Fold the misaligned u64 workarounds into the main quotactl flow instead of implementing a separate compat syscall handler. Signed-off-by: Christoph Hellwig Acked-by: Jan Kara Signed-off-by: Al Viro --- fs/quota/quota.c | 73 +++++++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 59 insertions(+), 14 deletions(-) (limited to 'fs/quota/quota.c') diff --git a/fs/quota/quota.c b/fs/quota/quota.c index 5444d3c4d93f..e1e9d05a14c3 100644 --- a/fs/quota/quota.c +++ b/fs/quota/quota.c @@ -19,6 +19,7 @@ #include #include #include +#include "compat.h" static int check_quotactl_permission(struct super_block *sb, int type, int cmd, qid_t id) @@ -211,8 +212,18 @@ static int quota_getquota(struct super_block *sb, int type, qid_t id, if (ret) return ret; copy_to_if_dqblk(&idq, &fdq); - if (copy_to_user(addr, &idq, sizeof(idq))) - return -EFAULT; + + if (compat_need_64bit_alignment_fixup()) { + struct compat_if_dqblk __user *compat_dqblk = addr; + + if (copy_to_user(compat_dqblk, &idq, sizeof(*compat_dqblk))) + return -EFAULT; + if (put_user(idq.dqb_valid, &compat_dqblk->dqb_valid)) + return -EFAULT; + } else { + if (copy_to_user(addr, &idq, sizeof(idq))) + return -EFAULT; + } return 0; } @@ -277,8 +288,16 @@ static int quota_setquota(struct super_block *sb, int type, qid_t id, struct if_dqblk idq; struct kqid qid; - if (copy_from_user(&idq, addr, sizeof(idq))) - return -EFAULT; + if (compat_need_64bit_alignment_fixup()) { + struct compat_if_dqblk __user *compat_dqblk = addr; + + if (copy_from_user(&idq, compat_dqblk, sizeof(*compat_dqblk)) || + get_user(idq.dqb_valid, &compat_dqblk->dqb_valid)) + return -EFAULT; + } else { + 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); @@ -382,6 +401,33 @@ static int quota_getstate(struct super_block *sb, int type, return 0; } +static int compat_copy_fs_qfilestat(struct compat_fs_qfilestat __user *to, + struct fs_qfilestat *from) +{ + if (copy_to_user(to, from, sizeof(*to)) || + put_user(from->qfs_nextents, &to->qfs_nextents)) + return -EFAULT; + return 0; +} + +static int compat_copy_fs_quota_stat(struct compat_fs_quota_stat __user *to, + struct fs_quota_stat *from) +{ + if (put_user(from->qs_version, &to->qs_version) || + put_user(from->qs_flags, &to->qs_flags) || + put_user(from->qs_pad, &to->qs_pad) || + compat_copy_fs_qfilestat(&to->qs_uquota, &from->qs_uquota) || + compat_copy_fs_qfilestat(&to->qs_gquota, &from->qs_gquota) || + put_user(from->qs_incoredqs, &to->qs_incoredqs) || + put_user(from->qs_btimelimit, &to->qs_btimelimit) || + put_user(from->qs_itimelimit, &to->qs_itimelimit) || + put_user(from->qs_rtbtimelimit, &to->qs_rtbtimelimit) || + put_user(from->qs_bwarnlimit, &to->qs_bwarnlimit) || + put_user(from->qs_iwarnlimit, &to->qs_iwarnlimit)) + return -EFAULT; + return 0; +} + static int quota_getxstate(struct super_block *sb, int type, void __user *addr) { struct fs_quota_stat fqs; @@ -390,9 +436,14 @@ static int quota_getxstate(struct super_block *sb, int type, void __user *addr) if (!sb->s_qcop->get_state) return -ENOSYS; ret = quota_getstate(sb, type, &fqs); - if (!ret && copy_to_user(addr, &fqs, sizeof(fqs))) + if (ret) + return ret; + + if (compat_need_64bit_alignment_fixup()) + return compat_copy_fs_quota_stat(addr, &fqs); + if (copy_to_user(addr, &fqs, sizeof(fqs))) return -EFAULT; - return ret; + return 0; } static int quota_getstatev(struct super_block *sb, int type, @@ -816,8 +867,8 @@ static struct super_block *quotactl_block(const char __user *special, int cmd) * calls. Maybe we need to add the process quotas etc. in the future, * but we probably should use rlimits for that. */ -int kernel_quotactl(unsigned int cmd, const char __user *special, - qid_t id, void __user *addr) +SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special, + qid_t, id, void __user *, addr) { uint cmds, type; struct super_block *sb = NULL; @@ -871,9 +922,3 @@ out: path_put(pathp); return ret; } - -SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special, - qid_t, id, void __user *, addr) -{ - return kernel_quotactl(cmd, special, id, addr); -} -- cgit v1.2.3