147e4937aSGao Xiang // SPDX-License-Identifier: GPL-2.0-only 247e4937aSGao Xiang /* 347e4937aSGao Xiang * Copyright (C) 2017-2018 HUAWEI, Inc. 4592e7cd0SAlexander A. Klimov * https://www.huawei.com/ 547e4937aSGao Xiang * Created by Gao Xiang <gaoxiang25@huawei.com> 647e4937aSGao Xiang */ 747e4937aSGao Xiang #include <linux/security.h> 847e4937aSGao Xiang #include "xattr.h" 947e4937aSGao Xiang 1047e4937aSGao Xiang struct xattr_iter { 1147e4937aSGao Xiang struct super_block *sb; 1247e4937aSGao Xiang struct page *page; 1347e4937aSGao Xiang void *kaddr; 1447e4937aSGao Xiang 1547e4937aSGao Xiang erofs_blk_t blkaddr; 1647e4937aSGao Xiang unsigned int ofs; 1747e4937aSGao Xiang }; 1847e4937aSGao Xiang 1947e4937aSGao Xiang static inline void xattr_iter_end(struct xattr_iter *it, bool atomic) 2047e4937aSGao Xiang { 2147e4937aSGao Xiang /* the only user of kunmap() is 'init_inode_xattrs' */ 228d8a09b0SGao Xiang if (!atomic) 2347e4937aSGao Xiang kunmap(it->page); 2447e4937aSGao Xiang else 2547e4937aSGao Xiang kunmap_atomic(it->kaddr); 2647e4937aSGao Xiang 2747e4937aSGao Xiang unlock_page(it->page); 2847e4937aSGao Xiang put_page(it->page); 2947e4937aSGao Xiang } 3047e4937aSGao Xiang 3147e4937aSGao Xiang static inline void xattr_iter_end_final(struct xattr_iter *it) 3247e4937aSGao Xiang { 3347e4937aSGao Xiang if (!it->page) 3447e4937aSGao Xiang return; 3547e4937aSGao Xiang 3647e4937aSGao Xiang xattr_iter_end(it, true); 3747e4937aSGao Xiang } 3847e4937aSGao Xiang 3947e4937aSGao Xiang static int init_inode_xattrs(struct inode *inode) 4047e4937aSGao Xiang { 41a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 4247e4937aSGao Xiang struct xattr_iter it; 4347e4937aSGao Xiang unsigned int i; 4447e4937aSGao Xiang struct erofs_xattr_ibody_header *ih; 4547e4937aSGao Xiang struct super_block *sb; 4647e4937aSGao Xiang struct erofs_sb_info *sbi; 4747e4937aSGao Xiang bool atomic_map; 4847e4937aSGao Xiang int ret = 0; 4947e4937aSGao Xiang 5047e4937aSGao Xiang /* the most case is that xattrs of this inode are initialized. */ 51*ce063129SGao Xiang if (test_bit(EROFS_I_EA_INITED_BIT, &vi->flags)) { 52*ce063129SGao Xiang /* 53*ce063129SGao Xiang * paired with smp_mb() at the end of the function to ensure 54*ce063129SGao Xiang * fields will only be observed after the bit is set. 55*ce063129SGao Xiang */ 56*ce063129SGao Xiang smp_mb(); 5747e4937aSGao Xiang return 0; 58*ce063129SGao Xiang } 5947e4937aSGao Xiang 60a5876e24SGao Xiang if (wait_on_bit_lock(&vi->flags, EROFS_I_BL_XATTR_BIT, TASK_KILLABLE)) 6147e4937aSGao Xiang return -ERESTARTSYS; 6247e4937aSGao Xiang 6347e4937aSGao Xiang /* someone has initialized xattrs for us? */ 64a5876e24SGao Xiang if (test_bit(EROFS_I_EA_INITED_BIT, &vi->flags)) 6547e4937aSGao Xiang goto out_unlock; 6647e4937aSGao Xiang 6747e4937aSGao Xiang /* 6847e4937aSGao Xiang * bypass all xattr operations if ->xattr_isize is not greater than 6947e4937aSGao Xiang * sizeof(struct erofs_xattr_ibody_header), in detail: 7047e4937aSGao Xiang * 1) it is not enough to contain erofs_xattr_ibody_header then 7147e4937aSGao Xiang * ->xattr_isize should be 0 (it means no xattr); 7247e4937aSGao Xiang * 2) it is just to contain erofs_xattr_ibody_header, which is on-disk 7347e4937aSGao Xiang * undefined right now (maybe use later with some new sb feature). 7447e4937aSGao Xiang */ 7547e4937aSGao Xiang if (vi->xattr_isize == sizeof(struct erofs_xattr_ibody_header)) { 764f761fa2SGao Xiang erofs_err(inode->i_sb, 774f761fa2SGao Xiang "xattr_isize %d of nid %llu is not supported yet", 7847e4937aSGao Xiang vi->xattr_isize, vi->nid); 7947e4937aSGao Xiang ret = -EOPNOTSUPP; 8047e4937aSGao Xiang goto out_unlock; 8147e4937aSGao Xiang } else if (vi->xattr_isize < sizeof(struct erofs_xattr_ibody_header)) { 828d8a09b0SGao Xiang if (vi->xattr_isize) { 834f761fa2SGao Xiang erofs_err(inode->i_sb, 844f761fa2SGao Xiang "bogus xattr ibody @ nid %llu", vi->nid); 8547e4937aSGao Xiang DBG_BUGON(1); 8647e4937aSGao Xiang ret = -EFSCORRUPTED; 8747e4937aSGao Xiang goto out_unlock; /* xattr ondisk layout error */ 8847e4937aSGao Xiang } 8947e4937aSGao Xiang ret = -ENOATTR; 9047e4937aSGao Xiang goto out_unlock; 9147e4937aSGao Xiang } 9247e4937aSGao Xiang 9347e4937aSGao Xiang sb = inode->i_sb; 9447e4937aSGao Xiang sbi = EROFS_SB(sb); 9547e4937aSGao Xiang it.blkaddr = erofs_blknr(iloc(sbi, vi->nid) + vi->inode_isize); 9647e4937aSGao Xiang it.ofs = erofs_blkoff(iloc(sbi, vi->nid) + vi->inode_isize); 9747e4937aSGao Xiang 98e655b5b3SGao Xiang it.page = erofs_get_meta_page(sb, it.blkaddr); 9947e4937aSGao Xiang if (IS_ERR(it.page)) { 10047e4937aSGao Xiang ret = PTR_ERR(it.page); 10147e4937aSGao Xiang goto out_unlock; 10247e4937aSGao Xiang } 10347e4937aSGao Xiang 10447e4937aSGao Xiang /* read in shared xattr array (non-atomic, see kmalloc below) */ 10547e4937aSGao Xiang it.kaddr = kmap(it.page); 10647e4937aSGao Xiang atomic_map = false; 10747e4937aSGao Xiang 10847e4937aSGao Xiang ih = (struct erofs_xattr_ibody_header *)(it.kaddr + it.ofs); 10947e4937aSGao Xiang 11047e4937aSGao Xiang vi->xattr_shared_count = ih->h_shared_count; 11147e4937aSGao Xiang vi->xattr_shared_xattrs = kmalloc_array(vi->xattr_shared_count, 11247e4937aSGao Xiang sizeof(uint), GFP_KERNEL); 11347e4937aSGao Xiang if (!vi->xattr_shared_xattrs) { 11447e4937aSGao Xiang xattr_iter_end(&it, atomic_map); 11547e4937aSGao Xiang ret = -ENOMEM; 11647e4937aSGao Xiang goto out_unlock; 11747e4937aSGao Xiang } 11847e4937aSGao Xiang 11947e4937aSGao Xiang /* let's skip ibody header */ 12047e4937aSGao Xiang it.ofs += sizeof(struct erofs_xattr_ibody_header); 12147e4937aSGao Xiang 12247e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 1238d8a09b0SGao Xiang if (it.ofs >= EROFS_BLKSIZ) { 12447e4937aSGao Xiang /* cannot be unaligned */ 12547e4937aSGao Xiang DBG_BUGON(it.ofs != EROFS_BLKSIZ); 12647e4937aSGao Xiang xattr_iter_end(&it, atomic_map); 12747e4937aSGao Xiang 128e655b5b3SGao Xiang it.page = erofs_get_meta_page(sb, ++it.blkaddr); 12947e4937aSGao Xiang if (IS_ERR(it.page)) { 13047e4937aSGao Xiang kfree(vi->xattr_shared_xattrs); 13147e4937aSGao Xiang vi->xattr_shared_xattrs = NULL; 13247e4937aSGao Xiang ret = PTR_ERR(it.page); 13347e4937aSGao Xiang goto out_unlock; 13447e4937aSGao Xiang } 13547e4937aSGao Xiang 13647e4937aSGao Xiang it.kaddr = kmap_atomic(it.page); 13747e4937aSGao Xiang atomic_map = true; 13847e4937aSGao Xiang it.ofs = 0; 13947e4937aSGao Xiang } 14047e4937aSGao Xiang vi->xattr_shared_xattrs[i] = 14147e4937aSGao Xiang le32_to_cpu(*(__le32 *)(it.kaddr + it.ofs)); 14247e4937aSGao Xiang it.ofs += sizeof(__le32); 14347e4937aSGao Xiang } 14447e4937aSGao Xiang xattr_iter_end(&it, atomic_map); 14547e4937aSGao Xiang 146*ce063129SGao Xiang /* paired with smp_mb() at the beginning of the function. */ 147*ce063129SGao Xiang smp_mb(); 148a5876e24SGao Xiang set_bit(EROFS_I_EA_INITED_BIT, &vi->flags); 14947e4937aSGao Xiang 15047e4937aSGao Xiang out_unlock: 151a5876e24SGao Xiang clear_and_wake_up_bit(EROFS_I_BL_XATTR_BIT, &vi->flags); 15247e4937aSGao Xiang return ret; 15347e4937aSGao Xiang } 15447e4937aSGao Xiang 15547e4937aSGao Xiang /* 15647e4937aSGao Xiang * the general idea for these return values is 15747e4937aSGao Xiang * if 0 is returned, go on processing the current xattr; 15847e4937aSGao Xiang * 1 (> 0) is returned, skip this round to process the next xattr; 15947e4937aSGao Xiang * -err (< 0) is returned, an error (maybe ENOXATTR) occurred 16047e4937aSGao Xiang * and need to be handled 16147e4937aSGao Xiang */ 16247e4937aSGao Xiang struct xattr_iter_handlers { 16347e4937aSGao Xiang int (*entry)(struct xattr_iter *_it, struct erofs_xattr_entry *entry); 16447e4937aSGao Xiang int (*name)(struct xattr_iter *_it, unsigned int processed, char *buf, 16547e4937aSGao Xiang unsigned int len); 16647e4937aSGao Xiang int (*alloc_buffer)(struct xattr_iter *_it, unsigned int value_sz); 16747e4937aSGao Xiang void (*value)(struct xattr_iter *_it, unsigned int processed, char *buf, 16847e4937aSGao Xiang unsigned int len); 16947e4937aSGao Xiang }; 17047e4937aSGao Xiang 17147e4937aSGao Xiang static inline int xattr_iter_fixup(struct xattr_iter *it) 17247e4937aSGao Xiang { 17347e4937aSGao Xiang if (it->ofs < EROFS_BLKSIZ) 17447e4937aSGao Xiang return 0; 17547e4937aSGao Xiang 17647e4937aSGao Xiang xattr_iter_end(it, true); 17747e4937aSGao Xiang 17847e4937aSGao Xiang it->blkaddr += erofs_blknr(it->ofs); 17947e4937aSGao Xiang 180e655b5b3SGao Xiang it->page = erofs_get_meta_page(it->sb, it->blkaddr); 18147e4937aSGao Xiang if (IS_ERR(it->page)) { 18247e4937aSGao Xiang int err = PTR_ERR(it->page); 18347e4937aSGao Xiang 18447e4937aSGao Xiang it->page = NULL; 18547e4937aSGao Xiang return err; 18647e4937aSGao Xiang } 18747e4937aSGao Xiang 18847e4937aSGao Xiang it->kaddr = kmap_atomic(it->page); 18947e4937aSGao Xiang it->ofs = erofs_blkoff(it->ofs); 19047e4937aSGao Xiang return 0; 19147e4937aSGao Xiang } 19247e4937aSGao Xiang 19347e4937aSGao Xiang static int inline_xattr_iter_begin(struct xattr_iter *it, 19447e4937aSGao Xiang struct inode *inode) 19547e4937aSGao Xiang { 196a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 19747e4937aSGao Xiang struct erofs_sb_info *const sbi = EROFS_SB(inode->i_sb); 19847e4937aSGao Xiang unsigned int xattr_header_sz, inline_xattr_ofs; 19947e4937aSGao Xiang 20047e4937aSGao Xiang xattr_header_sz = inlinexattr_header_size(inode); 2018d8a09b0SGao Xiang if (xattr_header_sz >= vi->xattr_isize) { 20247e4937aSGao Xiang DBG_BUGON(xattr_header_sz > vi->xattr_isize); 20347e4937aSGao Xiang return -ENOATTR; 20447e4937aSGao Xiang } 20547e4937aSGao Xiang 20647e4937aSGao Xiang inline_xattr_ofs = vi->inode_isize + xattr_header_sz; 20747e4937aSGao Xiang 20847e4937aSGao Xiang it->blkaddr = erofs_blknr(iloc(sbi, vi->nid) + inline_xattr_ofs); 20947e4937aSGao Xiang it->ofs = erofs_blkoff(iloc(sbi, vi->nid) + inline_xattr_ofs); 21047e4937aSGao Xiang 211e655b5b3SGao Xiang it->page = erofs_get_meta_page(inode->i_sb, it->blkaddr); 21247e4937aSGao Xiang if (IS_ERR(it->page)) 21347e4937aSGao Xiang return PTR_ERR(it->page); 21447e4937aSGao Xiang 21547e4937aSGao Xiang it->kaddr = kmap_atomic(it->page); 21647e4937aSGao Xiang return vi->xattr_isize - xattr_header_sz; 21747e4937aSGao Xiang } 21847e4937aSGao Xiang 21947e4937aSGao Xiang /* 22047e4937aSGao Xiang * Regardless of success or failure, `xattr_foreach' will end up with 22147e4937aSGao Xiang * `ofs' pointing to the next xattr item rather than an arbitrary position. 22247e4937aSGao Xiang */ 22347e4937aSGao Xiang static int xattr_foreach(struct xattr_iter *it, 22447e4937aSGao Xiang const struct xattr_iter_handlers *op, 22547e4937aSGao Xiang unsigned int *tlimit) 22647e4937aSGao Xiang { 22747e4937aSGao Xiang struct erofs_xattr_entry entry; 22847e4937aSGao Xiang unsigned int value_sz, processed, slice; 22947e4937aSGao Xiang int err; 23047e4937aSGao Xiang 23147e4937aSGao Xiang /* 0. fixup blkaddr, ofs, ipage */ 23247e4937aSGao Xiang err = xattr_iter_fixup(it); 23347e4937aSGao Xiang if (err) 23447e4937aSGao Xiang return err; 23547e4937aSGao Xiang 23647e4937aSGao Xiang /* 23747e4937aSGao Xiang * 1. read xattr entry to the memory, 23847e4937aSGao Xiang * since we do EROFS_XATTR_ALIGN 23947e4937aSGao Xiang * therefore entry should be in the page 24047e4937aSGao Xiang */ 24147e4937aSGao Xiang entry = *(struct erofs_xattr_entry *)(it->kaddr + it->ofs); 24247e4937aSGao Xiang if (tlimit) { 243b6796abdSGao Xiang unsigned int entry_sz = erofs_xattr_entry_size(&entry); 24447e4937aSGao Xiang 24547e4937aSGao Xiang /* xattr on-disk corruption: xattr entry beyond xattr_isize */ 2468d8a09b0SGao Xiang if (*tlimit < entry_sz) { 24747e4937aSGao Xiang DBG_BUGON(1); 24847e4937aSGao Xiang return -EFSCORRUPTED; 24947e4937aSGao Xiang } 25047e4937aSGao Xiang *tlimit -= entry_sz; 25147e4937aSGao Xiang } 25247e4937aSGao Xiang 25347e4937aSGao Xiang it->ofs += sizeof(struct erofs_xattr_entry); 25447e4937aSGao Xiang value_sz = le16_to_cpu(entry.e_value_size); 25547e4937aSGao Xiang 25647e4937aSGao Xiang /* handle entry */ 25747e4937aSGao Xiang err = op->entry(it, &entry); 25847e4937aSGao Xiang if (err) { 25947e4937aSGao Xiang it->ofs += entry.e_name_len + value_sz; 26047e4937aSGao Xiang goto out; 26147e4937aSGao Xiang } 26247e4937aSGao Xiang 26347e4937aSGao Xiang /* 2. handle xattr name (ofs will finally be at the end of name) */ 26447e4937aSGao Xiang processed = 0; 26547e4937aSGao Xiang 26647e4937aSGao Xiang while (processed < entry.e_name_len) { 26747e4937aSGao Xiang if (it->ofs >= EROFS_BLKSIZ) { 26847e4937aSGao Xiang DBG_BUGON(it->ofs > EROFS_BLKSIZ); 26947e4937aSGao Xiang 27047e4937aSGao Xiang err = xattr_iter_fixup(it); 27147e4937aSGao Xiang if (err) 27247e4937aSGao Xiang goto out; 27347e4937aSGao Xiang it->ofs = 0; 27447e4937aSGao Xiang } 27547e4937aSGao Xiang 27647e4937aSGao Xiang slice = min_t(unsigned int, PAGE_SIZE - it->ofs, 27747e4937aSGao Xiang entry.e_name_len - processed); 27847e4937aSGao Xiang 27947e4937aSGao Xiang /* handle name */ 28047e4937aSGao Xiang err = op->name(it, processed, it->kaddr + it->ofs, slice); 28147e4937aSGao Xiang if (err) { 28247e4937aSGao Xiang it->ofs += entry.e_name_len - processed + value_sz; 28347e4937aSGao Xiang goto out; 28447e4937aSGao Xiang } 28547e4937aSGao Xiang 28647e4937aSGao Xiang it->ofs += slice; 28747e4937aSGao Xiang processed += slice; 28847e4937aSGao Xiang } 28947e4937aSGao Xiang 29047e4937aSGao Xiang /* 3. handle xattr value */ 29147e4937aSGao Xiang processed = 0; 29247e4937aSGao Xiang 29347e4937aSGao Xiang if (op->alloc_buffer) { 29447e4937aSGao Xiang err = op->alloc_buffer(it, value_sz); 29547e4937aSGao Xiang if (err) { 29647e4937aSGao Xiang it->ofs += value_sz; 29747e4937aSGao Xiang goto out; 29847e4937aSGao Xiang } 29947e4937aSGao Xiang } 30047e4937aSGao Xiang 30147e4937aSGao Xiang while (processed < value_sz) { 30247e4937aSGao Xiang if (it->ofs >= EROFS_BLKSIZ) { 30347e4937aSGao Xiang DBG_BUGON(it->ofs > EROFS_BLKSIZ); 30447e4937aSGao Xiang 30547e4937aSGao Xiang err = xattr_iter_fixup(it); 30647e4937aSGao Xiang if (err) 30747e4937aSGao Xiang goto out; 30847e4937aSGao Xiang it->ofs = 0; 30947e4937aSGao Xiang } 31047e4937aSGao Xiang 31147e4937aSGao Xiang slice = min_t(unsigned int, PAGE_SIZE - it->ofs, 31247e4937aSGao Xiang value_sz - processed); 31347e4937aSGao Xiang op->value(it, processed, it->kaddr + it->ofs, slice); 31447e4937aSGao Xiang it->ofs += slice; 31547e4937aSGao Xiang processed += slice; 31647e4937aSGao Xiang } 31747e4937aSGao Xiang 31847e4937aSGao Xiang out: 31947e4937aSGao Xiang /* xattrs should be 4-byte aligned (on-disk constraint) */ 32047e4937aSGao Xiang it->ofs = EROFS_XATTR_ALIGN(it->ofs); 32147e4937aSGao Xiang return err < 0 ? err : 0; 32247e4937aSGao Xiang } 32347e4937aSGao Xiang 32447e4937aSGao Xiang struct getxattr_iter { 32547e4937aSGao Xiang struct xattr_iter it; 32647e4937aSGao Xiang 32747e4937aSGao Xiang char *buffer; 32847e4937aSGao Xiang int buffer_size, index; 32947e4937aSGao Xiang struct qstr name; 33047e4937aSGao Xiang }; 33147e4937aSGao Xiang 33247e4937aSGao Xiang static int xattr_entrymatch(struct xattr_iter *_it, 33347e4937aSGao Xiang struct erofs_xattr_entry *entry) 33447e4937aSGao Xiang { 33547e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 33647e4937aSGao Xiang 33747e4937aSGao Xiang return (it->index != entry->e_name_index || 33847e4937aSGao Xiang it->name.len != entry->e_name_len) ? -ENOATTR : 0; 33947e4937aSGao Xiang } 34047e4937aSGao Xiang 34147e4937aSGao Xiang static int xattr_namematch(struct xattr_iter *_it, 34247e4937aSGao Xiang unsigned int processed, char *buf, unsigned int len) 34347e4937aSGao Xiang { 34447e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 34547e4937aSGao Xiang 34647e4937aSGao Xiang return memcmp(buf, it->name.name + processed, len) ? -ENOATTR : 0; 34747e4937aSGao Xiang } 34847e4937aSGao Xiang 34947e4937aSGao Xiang static int xattr_checkbuffer(struct xattr_iter *_it, 35047e4937aSGao Xiang unsigned int value_sz) 35147e4937aSGao Xiang { 35247e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 35347e4937aSGao Xiang int err = it->buffer_size < value_sz ? -ERANGE : 0; 35447e4937aSGao Xiang 35547e4937aSGao Xiang it->buffer_size = value_sz; 35647e4937aSGao Xiang return !it->buffer ? 1 : err; 35747e4937aSGao Xiang } 35847e4937aSGao Xiang 35947e4937aSGao Xiang static void xattr_copyvalue(struct xattr_iter *_it, 36047e4937aSGao Xiang unsigned int processed, 36147e4937aSGao Xiang char *buf, unsigned int len) 36247e4937aSGao Xiang { 36347e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 36447e4937aSGao Xiang 36547e4937aSGao Xiang memcpy(it->buffer + processed, buf, len); 36647e4937aSGao Xiang } 36747e4937aSGao Xiang 36847e4937aSGao Xiang static const struct xattr_iter_handlers find_xattr_handlers = { 36947e4937aSGao Xiang .entry = xattr_entrymatch, 37047e4937aSGao Xiang .name = xattr_namematch, 37147e4937aSGao Xiang .alloc_buffer = xattr_checkbuffer, 37247e4937aSGao Xiang .value = xattr_copyvalue 37347e4937aSGao Xiang }; 37447e4937aSGao Xiang 37547e4937aSGao Xiang static int inline_getxattr(struct inode *inode, struct getxattr_iter *it) 37647e4937aSGao Xiang { 37747e4937aSGao Xiang int ret; 37847e4937aSGao Xiang unsigned int remaining; 37947e4937aSGao Xiang 38047e4937aSGao Xiang ret = inline_xattr_iter_begin(&it->it, inode); 38147e4937aSGao Xiang if (ret < 0) 38247e4937aSGao Xiang return ret; 38347e4937aSGao Xiang 38447e4937aSGao Xiang remaining = ret; 38547e4937aSGao Xiang while (remaining) { 38647e4937aSGao Xiang ret = xattr_foreach(&it->it, &find_xattr_handlers, &remaining); 38747e4937aSGao Xiang if (ret != -ENOATTR) 38847e4937aSGao Xiang break; 38947e4937aSGao Xiang } 39047e4937aSGao Xiang xattr_iter_end_final(&it->it); 39147e4937aSGao Xiang 39247e4937aSGao Xiang return ret ? ret : it->buffer_size; 39347e4937aSGao Xiang } 39447e4937aSGao Xiang 39547e4937aSGao Xiang static int shared_getxattr(struct inode *inode, struct getxattr_iter *it) 39647e4937aSGao Xiang { 397a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 39847e4937aSGao Xiang struct super_block *const sb = inode->i_sb; 39947e4937aSGao Xiang struct erofs_sb_info *const sbi = EROFS_SB(sb); 40047e4937aSGao Xiang unsigned int i; 40147e4937aSGao Xiang int ret = -ENOATTR; 40247e4937aSGao Xiang 40347e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 40447e4937aSGao Xiang erofs_blk_t blkaddr = 40547e4937aSGao Xiang xattrblock_addr(sbi, vi->xattr_shared_xattrs[i]); 40647e4937aSGao Xiang 40747e4937aSGao Xiang it->it.ofs = xattrblock_offset(sbi, vi->xattr_shared_xattrs[i]); 40847e4937aSGao Xiang 40947e4937aSGao Xiang if (!i || blkaddr != it->it.blkaddr) { 41047e4937aSGao Xiang if (i) 41147e4937aSGao Xiang xattr_iter_end(&it->it, true); 41247e4937aSGao Xiang 413e655b5b3SGao Xiang it->it.page = erofs_get_meta_page(sb, blkaddr); 41447e4937aSGao Xiang if (IS_ERR(it->it.page)) 41547e4937aSGao Xiang return PTR_ERR(it->it.page); 41647e4937aSGao Xiang 41747e4937aSGao Xiang it->it.kaddr = kmap_atomic(it->it.page); 41847e4937aSGao Xiang it->it.blkaddr = blkaddr; 41947e4937aSGao Xiang } 42047e4937aSGao Xiang 42147e4937aSGao Xiang ret = xattr_foreach(&it->it, &find_xattr_handlers, NULL); 42247e4937aSGao Xiang if (ret != -ENOATTR) 42347e4937aSGao Xiang break; 42447e4937aSGao Xiang } 42547e4937aSGao Xiang if (vi->xattr_shared_count) 42647e4937aSGao Xiang xattr_iter_end_final(&it->it); 42747e4937aSGao Xiang 42847e4937aSGao Xiang return ret ? ret : it->buffer_size; 42947e4937aSGao Xiang } 43047e4937aSGao Xiang 43147e4937aSGao Xiang static bool erofs_xattr_user_list(struct dentry *dentry) 43247e4937aSGao Xiang { 433f57a3fe4SChao Yu return test_opt(&EROFS_SB(dentry->d_sb)->ctx, XATTR_USER); 43447e4937aSGao Xiang } 43547e4937aSGao Xiang 43647e4937aSGao Xiang static bool erofs_xattr_trusted_list(struct dentry *dentry) 43747e4937aSGao Xiang { 43847e4937aSGao Xiang return capable(CAP_SYS_ADMIN); 43947e4937aSGao Xiang } 44047e4937aSGao Xiang 44147e4937aSGao Xiang int erofs_getxattr(struct inode *inode, int index, 44247e4937aSGao Xiang const char *name, 44347e4937aSGao Xiang void *buffer, size_t buffer_size) 44447e4937aSGao Xiang { 44547e4937aSGao Xiang int ret; 44647e4937aSGao Xiang struct getxattr_iter it; 44747e4937aSGao Xiang 4488d8a09b0SGao Xiang if (!name) 44947e4937aSGao Xiang return -EINVAL; 45047e4937aSGao Xiang 45147e4937aSGao Xiang ret = init_inode_xattrs(inode); 45247e4937aSGao Xiang if (ret) 45347e4937aSGao Xiang return ret; 45447e4937aSGao Xiang 45547e4937aSGao Xiang it.index = index; 45647e4937aSGao Xiang 45747e4937aSGao Xiang it.name.len = strlen(name); 45847e4937aSGao Xiang if (it.name.len > EROFS_NAME_LEN) 45947e4937aSGao Xiang return -ERANGE; 46047e4937aSGao Xiang it.name.name = name; 46147e4937aSGao Xiang 46247e4937aSGao Xiang it.buffer = buffer; 46347e4937aSGao Xiang it.buffer_size = buffer_size; 46447e4937aSGao Xiang 46547e4937aSGao Xiang it.it.sb = inode->i_sb; 46647e4937aSGao Xiang ret = inline_getxattr(inode, &it); 46747e4937aSGao Xiang if (ret == -ENOATTR) 46847e4937aSGao Xiang ret = shared_getxattr(inode, &it); 46947e4937aSGao Xiang return ret; 47047e4937aSGao Xiang } 47147e4937aSGao Xiang 47247e4937aSGao Xiang static int erofs_xattr_generic_get(const struct xattr_handler *handler, 47347e4937aSGao Xiang struct dentry *unused, struct inode *inode, 47447e4937aSGao Xiang const char *name, void *buffer, size_t size) 47547e4937aSGao Xiang { 47647e4937aSGao Xiang struct erofs_sb_info *const sbi = EROFS_I_SB(inode); 47747e4937aSGao Xiang 47847e4937aSGao Xiang switch (handler->flags) { 47947e4937aSGao Xiang case EROFS_XATTR_INDEX_USER: 480f57a3fe4SChao Yu if (!test_opt(&sbi->ctx, XATTR_USER)) 48147e4937aSGao Xiang return -EOPNOTSUPP; 48247e4937aSGao Xiang break; 48347e4937aSGao Xiang case EROFS_XATTR_INDEX_TRUSTED: 48447e4937aSGao Xiang break; 48547e4937aSGao Xiang case EROFS_XATTR_INDEX_SECURITY: 48647e4937aSGao Xiang break; 48747e4937aSGao Xiang default: 48847e4937aSGao Xiang return -EINVAL; 48947e4937aSGao Xiang } 49047e4937aSGao Xiang 49147e4937aSGao Xiang return erofs_getxattr(inode, handler->flags, name, buffer, size); 49247e4937aSGao Xiang } 49347e4937aSGao Xiang 49447e4937aSGao Xiang const struct xattr_handler erofs_xattr_user_handler = { 49547e4937aSGao Xiang .prefix = XATTR_USER_PREFIX, 49647e4937aSGao Xiang .flags = EROFS_XATTR_INDEX_USER, 49747e4937aSGao Xiang .list = erofs_xattr_user_list, 49847e4937aSGao Xiang .get = erofs_xattr_generic_get, 49947e4937aSGao Xiang }; 50047e4937aSGao Xiang 50147e4937aSGao Xiang const struct xattr_handler erofs_xattr_trusted_handler = { 50247e4937aSGao Xiang .prefix = XATTR_TRUSTED_PREFIX, 50347e4937aSGao Xiang .flags = EROFS_XATTR_INDEX_TRUSTED, 50447e4937aSGao Xiang .list = erofs_xattr_trusted_list, 50547e4937aSGao Xiang .get = erofs_xattr_generic_get, 50647e4937aSGao Xiang }; 50747e4937aSGao Xiang 50847e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_SECURITY 50947e4937aSGao Xiang const struct xattr_handler __maybe_unused erofs_xattr_security_handler = { 51047e4937aSGao Xiang .prefix = XATTR_SECURITY_PREFIX, 51147e4937aSGao Xiang .flags = EROFS_XATTR_INDEX_SECURITY, 51247e4937aSGao Xiang .get = erofs_xattr_generic_get, 51347e4937aSGao Xiang }; 51447e4937aSGao Xiang #endif 51547e4937aSGao Xiang 51647e4937aSGao Xiang const struct xattr_handler *erofs_xattr_handlers[] = { 51747e4937aSGao Xiang &erofs_xattr_user_handler, 51847e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_POSIX_ACL 51947e4937aSGao Xiang &posix_acl_access_xattr_handler, 52047e4937aSGao Xiang &posix_acl_default_xattr_handler, 52147e4937aSGao Xiang #endif 52247e4937aSGao Xiang &erofs_xattr_trusted_handler, 52347e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_SECURITY 52447e4937aSGao Xiang &erofs_xattr_security_handler, 52547e4937aSGao Xiang #endif 52647e4937aSGao Xiang NULL, 52747e4937aSGao Xiang }; 52847e4937aSGao Xiang 52947e4937aSGao Xiang struct listxattr_iter { 53047e4937aSGao Xiang struct xattr_iter it; 53147e4937aSGao Xiang 53247e4937aSGao Xiang struct dentry *dentry; 53347e4937aSGao Xiang char *buffer; 53447e4937aSGao Xiang int buffer_size, buffer_ofs; 53547e4937aSGao Xiang }; 53647e4937aSGao Xiang 53747e4937aSGao Xiang static int xattr_entrylist(struct xattr_iter *_it, 53847e4937aSGao Xiang struct erofs_xattr_entry *entry) 53947e4937aSGao Xiang { 54047e4937aSGao Xiang struct listxattr_iter *it = 54147e4937aSGao Xiang container_of(_it, struct listxattr_iter, it); 54247e4937aSGao Xiang unsigned int prefix_len; 54347e4937aSGao Xiang const char *prefix; 54447e4937aSGao Xiang 54547e4937aSGao Xiang const struct xattr_handler *h = 54647e4937aSGao Xiang erofs_xattr_handler(entry->e_name_index); 54747e4937aSGao Xiang 54847e4937aSGao Xiang if (!h || (h->list && !h->list(it->dentry))) 54947e4937aSGao Xiang return 1; 55047e4937aSGao Xiang 55147e4937aSGao Xiang prefix = xattr_prefix(h); 55247e4937aSGao Xiang prefix_len = strlen(prefix); 55347e4937aSGao Xiang 55447e4937aSGao Xiang if (!it->buffer) { 55547e4937aSGao Xiang it->buffer_ofs += prefix_len + entry->e_name_len + 1; 55647e4937aSGao Xiang return 1; 55747e4937aSGao Xiang } 55847e4937aSGao Xiang 55947e4937aSGao Xiang if (it->buffer_ofs + prefix_len 56047e4937aSGao Xiang + entry->e_name_len + 1 > it->buffer_size) 56147e4937aSGao Xiang return -ERANGE; 56247e4937aSGao Xiang 56347e4937aSGao Xiang memcpy(it->buffer + it->buffer_ofs, prefix, prefix_len); 56447e4937aSGao Xiang it->buffer_ofs += prefix_len; 56547e4937aSGao Xiang return 0; 56647e4937aSGao Xiang } 56747e4937aSGao Xiang 56847e4937aSGao Xiang static int xattr_namelist(struct xattr_iter *_it, 56947e4937aSGao Xiang unsigned int processed, char *buf, unsigned int len) 57047e4937aSGao Xiang { 57147e4937aSGao Xiang struct listxattr_iter *it = 57247e4937aSGao Xiang container_of(_it, struct listxattr_iter, it); 57347e4937aSGao Xiang 57447e4937aSGao Xiang memcpy(it->buffer + it->buffer_ofs, buf, len); 57547e4937aSGao Xiang it->buffer_ofs += len; 57647e4937aSGao Xiang return 0; 57747e4937aSGao Xiang } 57847e4937aSGao Xiang 57947e4937aSGao Xiang static int xattr_skipvalue(struct xattr_iter *_it, 58047e4937aSGao Xiang unsigned int value_sz) 58147e4937aSGao Xiang { 58247e4937aSGao Xiang struct listxattr_iter *it = 58347e4937aSGao Xiang container_of(_it, struct listxattr_iter, it); 58447e4937aSGao Xiang 58547e4937aSGao Xiang it->buffer[it->buffer_ofs++] = '\0'; 58647e4937aSGao Xiang return 1; 58747e4937aSGao Xiang } 58847e4937aSGao Xiang 58947e4937aSGao Xiang static const struct xattr_iter_handlers list_xattr_handlers = { 59047e4937aSGao Xiang .entry = xattr_entrylist, 59147e4937aSGao Xiang .name = xattr_namelist, 59247e4937aSGao Xiang .alloc_buffer = xattr_skipvalue, 59347e4937aSGao Xiang .value = NULL 59447e4937aSGao Xiang }; 59547e4937aSGao Xiang 59647e4937aSGao Xiang static int inline_listxattr(struct listxattr_iter *it) 59747e4937aSGao Xiang { 59847e4937aSGao Xiang int ret; 59947e4937aSGao Xiang unsigned int remaining; 60047e4937aSGao Xiang 60147e4937aSGao Xiang ret = inline_xattr_iter_begin(&it->it, d_inode(it->dentry)); 60247e4937aSGao Xiang if (ret < 0) 60347e4937aSGao Xiang return ret; 60447e4937aSGao Xiang 60547e4937aSGao Xiang remaining = ret; 60647e4937aSGao Xiang while (remaining) { 60747e4937aSGao Xiang ret = xattr_foreach(&it->it, &list_xattr_handlers, &remaining); 60847e4937aSGao Xiang if (ret) 60947e4937aSGao Xiang break; 61047e4937aSGao Xiang } 61147e4937aSGao Xiang xattr_iter_end_final(&it->it); 61247e4937aSGao Xiang return ret ? ret : it->buffer_ofs; 61347e4937aSGao Xiang } 61447e4937aSGao Xiang 61547e4937aSGao Xiang static int shared_listxattr(struct listxattr_iter *it) 61647e4937aSGao Xiang { 61747e4937aSGao Xiang struct inode *const inode = d_inode(it->dentry); 618a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 61947e4937aSGao Xiang struct super_block *const sb = inode->i_sb; 62047e4937aSGao Xiang struct erofs_sb_info *const sbi = EROFS_SB(sb); 62147e4937aSGao Xiang unsigned int i; 62247e4937aSGao Xiang int ret = 0; 62347e4937aSGao Xiang 62447e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 62547e4937aSGao Xiang erofs_blk_t blkaddr = 62647e4937aSGao Xiang xattrblock_addr(sbi, vi->xattr_shared_xattrs[i]); 62747e4937aSGao Xiang 62847e4937aSGao Xiang it->it.ofs = xattrblock_offset(sbi, vi->xattr_shared_xattrs[i]); 62947e4937aSGao Xiang if (!i || blkaddr != it->it.blkaddr) { 63047e4937aSGao Xiang if (i) 63147e4937aSGao Xiang xattr_iter_end(&it->it, true); 63247e4937aSGao Xiang 633e655b5b3SGao Xiang it->it.page = erofs_get_meta_page(sb, blkaddr); 63447e4937aSGao Xiang if (IS_ERR(it->it.page)) 63547e4937aSGao Xiang return PTR_ERR(it->it.page); 63647e4937aSGao Xiang 63747e4937aSGao Xiang it->it.kaddr = kmap_atomic(it->it.page); 63847e4937aSGao Xiang it->it.blkaddr = blkaddr; 63947e4937aSGao Xiang } 64047e4937aSGao Xiang 64147e4937aSGao Xiang ret = xattr_foreach(&it->it, &list_xattr_handlers, NULL); 64247e4937aSGao Xiang if (ret) 64347e4937aSGao Xiang break; 64447e4937aSGao Xiang } 64547e4937aSGao Xiang if (vi->xattr_shared_count) 64647e4937aSGao Xiang xattr_iter_end_final(&it->it); 64747e4937aSGao Xiang 64847e4937aSGao Xiang return ret ? ret : it->buffer_ofs; 64947e4937aSGao Xiang } 65047e4937aSGao Xiang 65147e4937aSGao Xiang ssize_t erofs_listxattr(struct dentry *dentry, 65247e4937aSGao Xiang char *buffer, size_t buffer_size) 65347e4937aSGao Xiang { 65447e4937aSGao Xiang int ret; 65547e4937aSGao Xiang struct listxattr_iter it; 65647e4937aSGao Xiang 65747e4937aSGao Xiang ret = init_inode_xattrs(d_inode(dentry)); 658926d1650SGao Xiang if (ret == -ENOATTR) 659926d1650SGao Xiang return 0; 66047e4937aSGao Xiang if (ret) 66147e4937aSGao Xiang return ret; 66247e4937aSGao Xiang 66347e4937aSGao Xiang it.dentry = dentry; 66447e4937aSGao Xiang it.buffer = buffer; 66547e4937aSGao Xiang it.buffer_size = buffer_size; 66647e4937aSGao Xiang it.buffer_ofs = 0; 66747e4937aSGao Xiang 66847e4937aSGao Xiang it.it.sb = dentry->d_sb; 66947e4937aSGao Xiang 67047e4937aSGao Xiang ret = inline_listxattr(&it); 67147e4937aSGao Xiang if (ret < 0 && ret != -ENOATTR) 67247e4937aSGao Xiang return ret; 67347e4937aSGao Xiang return shared_listxattr(&it); 67447e4937aSGao Xiang } 67547e4937aSGao Xiang 67647e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_POSIX_ACL 67747e4937aSGao Xiang struct posix_acl *erofs_get_acl(struct inode *inode, int type) 67847e4937aSGao Xiang { 67947e4937aSGao Xiang struct posix_acl *acl; 68047e4937aSGao Xiang int prefix, rc; 68147e4937aSGao Xiang char *value = NULL; 68247e4937aSGao Xiang 68347e4937aSGao Xiang switch (type) { 68447e4937aSGao Xiang case ACL_TYPE_ACCESS: 68547e4937aSGao Xiang prefix = EROFS_XATTR_INDEX_POSIX_ACL_ACCESS; 68647e4937aSGao Xiang break; 68747e4937aSGao Xiang case ACL_TYPE_DEFAULT: 68847e4937aSGao Xiang prefix = EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT; 68947e4937aSGao Xiang break; 69047e4937aSGao Xiang default: 69147e4937aSGao Xiang return ERR_PTR(-EINVAL); 69247e4937aSGao Xiang } 69347e4937aSGao Xiang 69447e4937aSGao Xiang rc = erofs_getxattr(inode, prefix, "", NULL, 0); 69547e4937aSGao Xiang if (rc > 0) { 69647e4937aSGao Xiang value = kmalloc(rc, GFP_KERNEL); 69747e4937aSGao Xiang if (!value) 69847e4937aSGao Xiang return ERR_PTR(-ENOMEM); 69947e4937aSGao Xiang rc = erofs_getxattr(inode, prefix, "", value, rc); 70047e4937aSGao Xiang } 70147e4937aSGao Xiang 70247e4937aSGao Xiang if (rc == -ENOATTR) 70347e4937aSGao Xiang acl = NULL; 70447e4937aSGao Xiang else if (rc < 0) 70547e4937aSGao Xiang acl = ERR_PTR(rc); 70647e4937aSGao Xiang else 70747e4937aSGao Xiang acl = posix_acl_from_xattr(&init_user_ns, value, rc); 70847e4937aSGao Xiang kfree(value); 70947e4937aSGao Xiang return acl; 71047e4937aSGao Xiang } 71147e4937aSGao Xiang #endif 71247e4937aSGao Xiang 713