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/ 5bb88e8daSGao Xiang * Copyright (C) 2021-2022, Alibaba Cloud 647e4937aSGao Xiang */ 747e4937aSGao Xiang #include <linux/security.h> 847e4937aSGao Xiang #include "xattr.h" 947e4937aSGao Xiang 10399f36d8SJingbo Xu static inline erofs_blk_t erofs_xattr_blkaddr(struct super_block *sb, 11399f36d8SJingbo Xu unsigned int xattr_id) 12399f36d8SJingbo Xu { 13399f36d8SJingbo Xu return EROFS_SB(sb)->xattr_blkaddr + 14399f36d8SJingbo Xu erofs_blknr(sb, xattr_id * sizeof(__u32)); 15399f36d8SJingbo Xu } 16399f36d8SJingbo Xu 17399f36d8SJingbo Xu static inline unsigned int erofs_xattr_blkoff(struct super_block *sb, 18399f36d8SJingbo Xu unsigned int xattr_id) 19399f36d8SJingbo Xu { 20399f36d8SJingbo Xu return erofs_blkoff(sb, xattr_id * sizeof(__u32)); 21399f36d8SJingbo Xu } 22399f36d8SJingbo Xu 2347e4937aSGao Xiang struct xattr_iter { 2447e4937aSGao Xiang struct super_block *sb; 25bb88e8daSGao Xiang struct erofs_buf buf; 2647e4937aSGao Xiang void *kaddr; 2747e4937aSGao Xiang 2847e4937aSGao Xiang erofs_blk_t blkaddr; 2947e4937aSGao Xiang unsigned int ofs; 3047e4937aSGao Xiang }; 3147e4937aSGao Xiang 326020ffe7SJingbo Xu static int erofs_init_inode_xattrs(struct inode *inode) 3347e4937aSGao Xiang { 34a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 3547e4937aSGao Xiang struct xattr_iter it; 3647e4937aSGao Xiang unsigned int i; 3747e4937aSGao Xiang struct erofs_xattr_ibody_header *ih; 38b780d3fcSGao Xiang struct super_block *sb = inode->i_sb; 3947e4937aSGao Xiang int ret = 0; 4047e4937aSGao Xiang 4147e4937aSGao Xiang /* the most case is that xattrs of this inode are initialized. */ 42ce063129SGao Xiang if (test_bit(EROFS_I_EA_INITED_BIT, &vi->flags)) { 43ce063129SGao Xiang /* 44ce063129SGao Xiang * paired with smp_mb() at the end of the function to ensure 45ce063129SGao Xiang * fields will only be observed after the bit is set. 46ce063129SGao Xiang */ 47ce063129SGao Xiang smp_mb(); 4847e4937aSGao Xiang return 0; 49ce063129SGao Xiang } 5047e4937aSGao Xiang 51a5876e24SGao Xiang if (wait_on_bit_lock(&vi->flags, EROFS_I_BL_XATTR_BIT, TASK_KILLABLE)) 5247e4937aSGao Xiang return -ERESTARTSYS; 5347e4937aSGao Xiang 5447e4937aSGao Xiang /* someone has initialized xattrs for us? */ 55a5876e24SGao Xiang if (test_bit(EROFS_I_EA_INITED_BIT, &vi->flags)) 5647e4937aSGao Xiang goto out_unlock; 5747e4937aSGao Xiang 5847e4937aSGao Xiang /* 5947e4937aSGao Xiang * bypass all xattr operations if ->xattr_isize is not greater than 6047e4937aSGao Xiang * sizeof(struct erofs_xattr_ibody_header), in detail: 6147e4937aSGao Xiang * 1) it is not enough to contain erofs_xattr_ibody_header then 6247e4937aSGao Xiang * ->xattr_isize should be 0 (it means no xattr); 6347e4937aSGao Xiang * 2) it is just to contain erofs_xattr_ibody_header, which is on-disk 6447e4937aSGao Xiang * undefined right now (maybe use later with some new sb feature). 6547e4937aSGao Xiang */ 6647e4937aSGao Xiang if (vi->xattr_isize == sizeof(struct erofs_xattr_ibody_header)) { 67b780d3fcSGao Xiang erofs_err(sb, 684f761fa2SGao Xiang "xattr_isize %d of nid %llu is not supported yet", 6947e4937aSGao Xiang vi->xattr_isize, vi->nid); 7047e4937aSGao Xiang ret = -EOPNOTSUPP; 7147e4937aSGao Xiang goto out_unlock; 7247e4937aSGao Xiang } else if (vi->xattr_isize < sizeof(struct erofs_xattr_ibody_header)) { 738d8a09b0SGao Xiang if (vi->xattr_isize) { 74b780d3fcSGao Xiang erofs_err(sb, "bogus xattr ibody @ nid %llu", vi->nid); 7547e4937aSGao Xiang DBG_BUGON(1); 7647e4937aSGao Xiang ret = -EFSCORRUPTED; 7747e4937aSGao Xiang goto out_unlock; /* xattr ondisk layout error */ 7847e4937aSGao Xiang } 7947e4937aSGao Xiang ret = -ENOATTR; 8047e4937aSGao Xiang goto out_unlock; 8147e4937aSGao Xiang } 8247e4937aSGao Xiang 83bb88e8daSGao Xiang it.buf = __EROFS_BUF_INITIALIZER; 84*9c39ec0cSJingbo Xu erofs_init_metabuf(&it.buf, sb); 853acea5fcSJingbo Xu it.blkaddr = erofs_blknr(sb, erofs_iloc(inode) + vi->inode_isize); 863acea5fcSJingbo Xu it.ofs = erofs_blkoff(sb, erofs_iloc(inode) + vi->inode_isize); 8747e4937aSGao Xiang 88bb88e8daSGao Xiang /* read in shared xattr array (non-atomic, see kmalloc below) */ 89*9c39ec0cSJingbo Xu it.kaddr = erofs_bread(&it.buf, it.blkaddr, EROFS_KMAP); 90bb88e8daSGao Xiang if (IS_ERR(it.kaddr)) { 91bb88e8daSGao Xiang ret = PTR_ERR(it.kaddr); 9247e4937aSGao Xiang goto out_unlock; 9347e4937aSGao Xiang } 9447e4937aSGao Xiang 9547e4937aSGao Xiang ih = (struct erofs_xattr_ibody_header *)(it.kaddr + it.ofs); 9647e4937aSGao Xiang vi->xattr_shared_count = ih->h_shared_count; 9747e4937aSGao Xiang vi->xattr_shared_xattrs = kmalloc_array(vi->xattr_shared_count, 9847e4937aSGao Xiang sizeof(uint), GFP_KERNEL); 9947e4937aSGao Xiang if (!vi->xattr_shared_xattrs) { 100bb88e8daSGao Xiang erofs_put_metabuf(&it.buf); 10147e4937aSGao Xiang ret = -ENOMEM; 10247e4937aSGao Xiang goto out_unlock; 10347e4937aSGao Xiang } 10447e4937aSGao Xiang 10547e4937aSGao Xiang /* let's skip ibody header */ 10647e4937aSGao Xiang it.ofs += sizeof(struct erofs_xattr_ibody_header); 10747e4937aSGao Xiang 10847e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 1093acea5fcSJingbo Xu if (it.ofs >= sb->s_blocksize) { 11047e4937aSGao Xiang /* cannot be unaligned */ 1113acea5fcSJingbo Xu DBG_BUGON(it.ofs != sb->s_blocksize); 11247e4937aSGao Xiang 113*9c39ec0cSJingbo Xu it.kaddr = erofs_bread(&it.buf, ++it.blkaddr, EROFS_KMAP); 114bb88e8daSGao Xiang if (IS_ERR(it.kaddr)) { 11547e4937aSGao Xiang kfree(vi->xattr_shared_xattrs); 11647e4937aSGao Xiang vi->xattr_shared_xattrs = NULL; 117bb88e8daSGao Xiang ret = PTR_ERR(it.kaddr); 11847e4937aSGao Xiang goto out_unlock; 11947e4937aSGao Xiang } 12047e4937aSGao Xiang it.ofs = 0; 12147e4937aSGao Xiang } 12247e4937aSGao Xiang vi->xattr_shared_xattrs[i] = 12347e4937aSGao Xiang le32_to_cpu(*(__le32 *)(it.kaddr + it.ofs)); 12447e4937aSGao Xiang it.ofs += sizeof(__le32); 12547e4937aSGao Xiang } 126bb88e8daSGao Xiang erofs_put_metabuf(&it.buf); 12747e4937aSGao Xiang 128ce063129SGao Xiang /* paired with smp_mb() at the beginning of the function. */ 129ce063129SGao Xiang smp_mb(); 130a5876e24SGao Xiang set_bit(EROFS_I_EA_INITED_BIT, &vi->flags); 13147e4937aSGao Xiang 13247e4937aSGao Xiang out_unlock: 133a5876e24SGao Xiang clear_and_wake_up_bit(EROFS_I_BL_XATTR_BIT, &vi->flags); 13447e4937aSGao Xiang return ret; 13547e4937aSGao Xiang } 13647e4937aSGao Xiang 13747e4937aSGao Xiang /* 13847e4937aSGao Xiang * the general idea for these return values is 13947e4937aSGao Xiang * if 0 is returned, go on processing the current xattr; 14047e4937aSGao Xiang * 1 (> 0) is returned, skip this round to process the next xattr; 14147e4937aSGao Xiang * -err (< 0) is returned, an error (maybe ENOXATTR) occurred 14247e4937aSGao Xiang * and need to be handled 14347e4937aSGao Xiang */ 14447e4937aSGao Xiang struct xattr_iter_handlers { 14547e4937aSGao Xiang int (*entry)(struct xattr_iter *_it, struct erofs_xattr_entry *entry); 14647e4937aSGao Xiang int (*name)(struct xattr_iter *_it, unsigned int processed, char *buf, 14747e4937aSGao Xiang unsigned int len); 14847e4937aSGao Xiang int (*alloc_buffer)(struct xattr_iter *_it, unsigned int value_sz); 14947e4937aSGao Xiang void (*value)(struct xattr_iter *_it, unsigned int processed, char *buf, 15047e4937aSGao Xiang unsigned int len); 15147e4937aSGao Xiang }; 15247e4937aSGao Xiang 15347e4937aSGao Xiang static inline int xattr_iter_fixup(struct xattr_iter *it) 15447e4937aSGao Xiang { 1553acea5fcSJingbo Xu if (it->ofs < it->sb->s_blocksize) 15647e4937aSGao Xiang return 0; 15747e4937aSGao Xiang 1583acea5fcSJingbo Xu it->blkaddr += erofs_blknr(it->sb, it->ofs); 159*9c39ec0cSJingbo Xu it->kaddr = erofs_bread(&it->buf, it->blkaddr, EROFS_KMAP); 160bb88e8daSGao Xiang if (IS_ERR(it->kaddr)) 161bb88e8daSGao Xiang return PTR_ERR(it->kaddr); 1623acea5fcSJingbo Xu it->ofs = erofs_blkoff(it->sb, it->ofs); 16347e4937aSGao Xiang return 0; 16447e4937aSGao Xiang } 16547e4937aSGao Xiang 16647e4937aSGao Xiang static int inline_xattr_iter_begin(struct xattr_iter *it, 16747e4937aSGao Xiang struct inode *inode) 16847e4937aSGao Xiang { 169a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 17047e4937aSGao Xiang unsigned int xattr_header_sz, inline_xattr_ofs; 17147e4937aSGao Xiang 172399f36d8SJingbo Xu xattr_header_sz = sizeof(struct erofs_xattr_ibody_header) + 173399f36d8SJingbo Xu sizeof(u32) * vi->xattr_shared_count; 1748d8a09b0SGao Xiang if (xattr_header_sz >= vi->xattr_isize) { 17547e4937aSGao Xiang DBG_BUGON(xattr_header_sz > vi->xattr_isize); 17647e4937aSGao Xiang return -ENOATTR; 17747e4937aSGao Xiang } 17847e4937aSGao Xiang 17947e4937aSGao Xiang inline_xattr_ofs = vi->inode_isize + xattr_header_sz; 18047e4937aSGao Xiang 1813acea5fcSJingbo Xu it->blkaddr = erofs_blknr(it->sb, erofs_iloc(inode) + inline_xattr_ofs); 1823acea5fcSJingbo Xu it->ofs = erofs_blkoff(it->sb, erofs_iloc(inode) + inline_xattr_ofs); 183*9c39ec0cSJingbo Xu it->kaddr = erofs_bread(&it->buf, it->blkaddr, EROFS_KMAP); 184bb88e8daSGao Xiang if (IS_ERR(it->kaddr)) 185bb88e8daSGao Xiang return PTR_ERR(it->kaddr); 18647e4937aSGao Xiang return vi->xattr_isize - xattr_header_sz; 18747e4937aSGao Xiang } 18847e4937aSGao Xiang 18947e4937aSGao Xiang /* 19047e4937aSGao Xiang * Regardless of success or failure, `xattr_foreach' will end up with 19147e4937aSGao Xiang * `ofs' pointing to the next xattr item rather than an arbitrary position. 19247e4937aSGao Xiang */ 19347e4937aSGao Xiang static int xattr_foreach(struct xattr_iter *it, 19447e4937aSGao Xiang const struct xattr_iter_handlers *op, 19547e4937aSGao Xiang unsigned int *tlimit) 19647e4937aSGao Xiang { 19747e4937aSGao Xiang struct erofs_xattr_entry entry; 19847e4937aSGao Xiang unsigned int value_sz, processed, slice; 19947e4937aSGao Xiang int err; 20047e4937aSGao Xiang 20147e4937aSGao Xiang /* 0. fixup blkaddr, ofs, ipage */ 20247e4937aSGao Xiang err = xattr_iter_fixup(it); 20347e4937aSGao Xiang if (err) 20447e4937aSGao Xiang return err; 20547e4937aSGao Xiang 20647e4937aSGao Xiang /* 20747e4937aSGao Xiang * 1. read xattr entry to the memory, 20847e4937aSGao Xiang * since we do EROFS_XATTR_ALIGN 20947e4937aSGao Xiang * therefore entry should be in the page 21047e4937aSGao Xiang */ 21147e4937aSGao Xiang entry = *(struct erofs_xattr_entry *)(it->kaddr + it->ofs); 21247e4937aSGao Xiang if (tlimit) { 213b6796abdSGao Xiang unsigned int entry_sz = erofs_xattr_entry_size(&entry); 21447e4937aSGao Xiang 21547e4937aSGao Xiang /* xattr on-disk corruption: xattr entry beyond xattr_isize */ 2168d8a09b0SGao Xiang if (*tlimit < entry_sz) { 21747e4937aSGao Xiang DBG_BUGON(1); 21847e4937aSGao Xiang return -EFSCORRUPTED; 21947e4937aSGao Xiang } 22047e4937aSGao Xiang *tlimit -= entry_sz; 22147e4937aSGao Xiang } 22247e4937aSGao Xiang 22347e4937aSGao Xiang it->ofs += sizeof(struct erofs_xattr_entry); 22447e4937aSGao Xiang value_sz = le16_to_cpu(entry.e_value_size); 22547e4937aSGao Xiang 22647e4937aSGao Xiang /* handle entry */ 22747e4937aSGao Xiang err = op->entry(it, &entry); 22847e4937aSGao Xiang if (err) { 22947e4937aSGao Xiang it->ofs += entry.e_name_len + value_sz; 23047e4937aSGao Xiang goto out; 23147e4937aSGao Xiang } 23247e4937aSGao Xiang 23347e4937aSGao Xiang /* 2. handle xattr name (ofs will finally be at the end of name) */ 23447e4937aSGao Xiang processed = 0; 23547e4937aSGao Xiang 23647e4937aSGao Xiang while (processed < entry.e_name_len) { 2373acea5fcSJingbo Xu if (it->ofs >= it->sb->s_blocksize) { 2383acea5fcSJingbo Xu DBG_BUGON(it->ofs > it->sb->s_blocksize); 23947e4937aSGao Xiang 24047e4937aSGao Xiang err = xattr_iter_fixup(it); 24147e4937aSGao Xiang if (err) 24247e4937aSGao Xiang goto out; 24347e4937aSGao Xiang it->ofs = 0; 24447e4937aSGao Xiang } 24547e4937aSGao Xiang 2463acea5fcSJingbo Xu slice = min_t(unsigned int, it->sb->s_blocksize - it->ofs, 24747e4937aSGao Xiang entry.e_name_len - processed); 24847e4937aSGao Xiang 24947e4937aSGao Xiang /* handle name */ 25047e4937aSGao Xiang err = op->name(it, processed, it->kaddr + it->ofs, slice); 25147e4937aSGao Xiang if (err) { 25247e4937aSGao Xiang it->ofs += entry.e_name_len - processed + value_sz; 25347e4937aSGao Xiang goto out; 25447e4937aSGao Xiang } 25547e4937aSGao Xiang 25647e4937aSGao Xiang it->ofs += slice; 25747e4937aSGao Xiang processed += slice; 25847e4937aSGao Xiang } 25947e4937aSGao Xiang 26047e4937aSGao Xiang /* 3. handle xattr value */ 26147e4937aSGao Xiang processed = 0; 26247e4937aSGao Xiang 26347e4937aSGao Xiang if (op->alloc_buffer) { 26447e4937aSGao Xiang err = op->alloc_buffer(it, value_sz); 26547e4937aSGao Xiang if (err) { 26647e4937aSGao Xiang it->ofs += value_sz; 26747e4937aSGao Xiang goto out; 26847e4937aSGao Xiang } 26947e4937aSGao Xiang } 27047e4937aSGao Xiang 27147e4937aSGao Xiang while (processed < value_sz) { 2723acea5fcSJingbo Xu if (it->ofs >= it->sb->s_blocksize) { 2733acea5fcSJingbo Xu DBG_BUGON(it->ofs > it->sb->s_blocksize); 27447e4937aSGao Xiang 27547e4937aSGao Xiang err = xattr_iter_fixup(it); 27647e4937aSGao Xiang if (err) 27747e4937aSGao Xiang goto out; 27847e4937aSGao Xiang it->ofs = 0; 27947e4937aSGao Xiang } 28047e4937aSGao Xiang 2813acea5fcSJingbo Xu slice = min_t(unsigned int, it->sb->s_blocksize - it->ofs, 28247e4937aSGao Xiang value_sz - processed); 28347e4937aSGao Xiang op->value(it, processed, it->kaddr + it->ofs, slice); 28447e4937aSGao Xiang it->ofs += slice; 28547e4937aSGao Xiang processed += slice; 28647e4937aSGao Xiang } 28747e4937aSGao Xiang 28847e4937aSGao Xiang out: 28947e4937aSGao Xiang /* xattrs should be 4-byte aligned (on-disk constraint) */ 29047e4937aSGao Xiang it->ofs = EROFS_XATTR_ALIGN(it->ofs); 29147e4937aSGao Xiang return err < 0 ? err : 0; 29247e4937aSGao Xiang } 29347e4937aSGao Xiang 29447e4937aSGao Xiang struct getxattr_iter { 29547e4937aSGao Xiang struct xattr_iter it; 29647e4937aSGao Xiang 29747e4937aSGao Xiang char *buffer; 29882bc1ef4SJingbo Xu int buffer_size, index, infix_len; 29947e4937aSGao Xiang struct qstr name; 30047e4937aSGao Xiang }; 30147e4937aSGao Xiang 30282bc1ef4SJingbo Xu static int erofs_xattr_long_entrymatch(struct getxattr_iter *it, 30382bc1ef4SJingbo Xu struct erofs_xattr_entry *entry) 30482bc1ef4SJingbo Xu { 30582bc1ef4SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(it->it.sb); 30682bc1ef4SJingbo Xu struct erofs_xattr_prefix_item *pf = sbi->xattr_prefixes + 30782bc1ef4SJingbo Xu (entry->e_name_index & EROFS_XATTR_LONG_PREFIX_MASK); 30882bc1ef4SJingbo Xu 30982bc1ef4SJingbo Xu if (pf >= sbi->xattr_prefixes + sbi->xattr_prefix_count) 31082bc1ef4SJingbo Xu return -ENOATTR; 31182bc1ef4SJingbo Xu 31282bc1ef4SJingbo Xu if (it->index != pf->prefix->base_index || 31382bc1ef4SJingbo Xu it->name.len != entry->e_name_len + pf->infix_len) 31482bc1ef4SJingbo Xu return -ENOATTR; 31582bc1ef4SJingbo Xu 31682bc1ef4SJingbo Xu if (memcmp(it->name.name, pf->prefix->infix, pf->infix_len)) 31782bc1ef4SJingbo Xu return -ENOATTR; 31882bc1ef4SJingbo Xu 31982bc1ef4SJingbo Xu it->infix_len = pf->infix_len; 32082bc1ef4SJingbo Xu return 0; 32182bc1ef4SJingbo Xu } 32282bc1ef4SJingbo Xu 32347e4937aSGao Xiang static int xattr_entrymatch(struct xattr_iter *_it, 32447e4937aSGao Xiang struct erofs_xattr_entry *entry) 32547e4937aSGao Xiang { 32647e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 32747e4937aSGao Xiang 32882bc1ef4SJingbo Xu /* should also match the infix for long name prefixes */ 32982bc1ef4SJingbo Xu if (entry->e_name_index & EROFS_XATTR_LONG_PREFIX) 33082bc1ef4SJingbo Xu return erofs_xattr_long_entrymatch(it, entry); 33182bc1ef4SJingbo Xu 33282bc1ef4SJingbo Xu if (it->index != entry->e_name_index || 33382bc1ef4SJingbo Xu it->name.len != entry->e_name_len) 33482bc1ef4SJingbo Xu return -ENOATTR; 33582bc1ef4SJingbo Xu it->infix_len = 0; 33682bc1ef4SJingbo Xu return 0; 33747e4937aSGao Xiang } 33847e4937aSGao Xiang 33947e4937aSGao Xiang static int xattr_namematch(struct xattr_iter *_it, 34047e4937aSGao Xiang unsigned int processed, char *buf, unsigned int len) 34147e4937aSGao Xiang { 34247e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 34347e4937aSGao Xiang 34482bc1ef4SJingbo Xu if (memcmp(buf, it->name.name + it->infix_len + processed, len)) 34582bc1ef4SJingbo Xu return -ENOATTR; 34682bc1ef4SJingbo Xu return 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 return ret ? ret : it->buffer_size; 39147e4937aSGao Xiang } 39247e4937aSGao Xiang 39347e4937aSGao Xiang static int shared_getxattr(struct inode *inode, struct getxattr_iter *it) 39447e4937aSGao Xiang { 395a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 396399f36d8SJingbo Xu struct super_block *const sb = it->it.sb; 397399f36d8SJingbo Xu unsigned int i, xsid; 39847e4937aSGao Xiang int ret = -ENOATTR; 39947e4937aSGao Xiang 40047e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 401399f36d8SJingbo Xu xsid = vi->xattr_shared_xattrs[i]; 402399f36d8SJingbo Xu it->it.blkaddr = erofs_xattr_blkaddr(sb, xsid); 403399f36d8SJingbo Xu it->it.ofs = erofs_xattr_blkoff(sb, xsid); 404*9c39ec0cSJingbo Xu it->it.kaddr = erofs_bread(&it->it.buf, it->it.blkaddr, EROFS_KMAP); 405bb88e8daSGao Xiang if (IS_ERR(it->it.kaddr)) 406bb88e8daSGao Xiang return PTR_ERR(it->it.kaddr); 40747e4937aSGao Xiang 40847e4937aSGao Xiang ret = xattr_foreach(&it->it, &find_xattr_handlers, NULL); 40947e4937aSGao Xiang if (ret != -ENOATTR) 41047e4937aSGao Xiang break; 41147e4937aSGao Xiang } 41247e4937aSGao Xiang return ret ? ret : it->buffer_size; 41347e4937aSGao Xiang } 41447e4937aSGao Xiang 41547e4937aSGao Xiang static bool erofs_xattr_user_list(struct dentry *dentry) 41647e4937aSGao Xiang { 417e6242465SGao Xiang return test_opt(&EROFS_SB(dentry->d_sb)->opt, XATTR_USER); 41847e4937aSGao Xiang } 41947e4937aSGao Xiang 42047e4937aSGao Xiang static bool erofs_xattr_trusted_list(struct dentry *dentry) 42147e4937aSGao Xiang { 42247e4937aSGao Xiang return capable(CAP_SYS_ADMIN); 42347e4937aSGao Xiang } 42447e4937aSGao Xiang 42547e4937aSGao Xiang int erofs_getxattr(struct inode *inode, int index, 42647e4937aSGao Xiang const char *name, 42747e4937aSGao Xiang void *buffer, size_t buffer_size) 42847e4937aSGao Xiang { 42947e4937aSGao Xiang int ret; 43047e4937aSGao Xiang struct getxattr_iter it; 43147e4937aSGao Xiang 4328d8a09b0SGao Xiang if (!name) 43347e4937aSGao Xiang return -EINVAL; 43447e4937aSGao Xiang 4356020ffe7SJingbo Xu ret = erofs_init_inode_xattrs(inode); 43647e4937aSGao Xiang if (ret) 43747e4937aSGao Xiang return ret; 43847e4937aSGao Xiang 43947e4937aSGao Xiang it.index = index; 44047e4937aSGao Xiang it.name.len = strlen(name); 44147e4937aSGao Xiang if (it.name.len > EROFS_NAME_LEN) 44247e4937aSGao Xiang return -ERANGE; 443bb88e8daSGao Xiang 444*9c39ec0cSJingbo Xu it.it.sb = inode->i_sb; 445bb88e8daSGao Xiang it.it.buf = __EROFS_BUF_INITIALIZER; 446*9c39ec0cSJingbo Xu erofs_init_metabuf(&it.it.buf, it.it.sb); 44747e4937aSGao Xiang it.name.name = name; 44847e4937aSGao Xiang 44947e4937aSGao Xiang it.buffer = buffer; 45047e4937aSGao Xiang it.buffer_size = buffer_size; 45147e4937aSGao Xiang 45247e4937aSGao Xiang ret = inline_getxattr(inode, &it); 45347e4937aSGao Xiang if (ret == -ENOATTR) 45447e4937aSGao Xiang ret = shared_getxattr(inode, &it); 455bb88e8daSGao Xiang erofs_put_metabuf(&it.it.buf); 45647e4937aSGao Xiang return ret; 45747e4937aSGao Xiang } 45847e4937aSGao Xiang 45947e4937aSGao Xiang static int erofs_xattr_generic_get(const struct xattr_handler *handler, 46047e4937aSGao Xiang struct dentry *unused, struct inode *inode, 46147e4937aSGao Xiang const char *name, void *buffer, size_t size) 46247e4937aSGao Xiang { 463b05f30bcSJingbo Xu if (handler->flags == EROFS_XATTR_INDEX_USER && 464b05f30bcSJingbo Xu !test_opt(&EROFS_I_SB(inode)->opt, XATTR_USER)) 46547e4937aSGao Xiang return -EOPNOTSUPP; 46647e4937aSGao Xiang 46747e4937aSGao Xiang return erofs_getxattr(inode, handler->flags, name, buffer, size); 46847e4937aSGao Xiang } 46947e4937aSGao Xiang 47047e4937aSGao Xiang const struct xattr_handler erofs_xattr_user_handler = { 47147e4937aSGao Xiang .prefix = XATTR_USER_PREFIX, 47247e4937aSGao Xiang .flags = EROFS_XATTR_INDEX_USER, 47347e4937aSGao Xiang .list = erofs_xattr_user_list, 47447e4937aSGao Xiang .get = erofs_xattr_generic_get, 47547e4937aSGao Xiang }; 47647e4937aSGao Xiang 47747e4937aSGao Xiang const struct xattr_handler erofs_xattr_trusted_handler = { 47847e4937aSGao Xiang .prefix = XATTR_TRUSTED_PREFIX, 47947e4937aSGao Xiang .flags = EROFS_XATTR_INDEX_TRUSTED, 48047e4937aSGao Xiang .list = erofs_xattr_trusted_list, 48147e4937aSGao Xiang .get = erofs_xattr_generic_get, 48247e4937aSGao Xiang }; 48347e4937aSGao Xiang 48447e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_SECURITY 48547e4937aSGao Xiang const struct xattr_handler __maybe_unused erofs_xattr_security_handler = { 48647e4937aSGao Xiang .prefix = XATTR_SECURITY_PREFIX, 48747e4937aSGao Xiang .flags = EROFS_XATTR_INDEX_SECURITY, 48847e4937aSGao Xiang .get = erofs_xattr_generic_get, 48947e4937aSGao Xiang }; 49047e4937aSGao Xiang #endif 49147e4937aSGao Xiang 49247e4937aSGao Xiang const struct xattr_handler *erofs_xattr_handlers[] = { 49347e4937aSGao Xiang &erofs_xattr_user_handler, 49447e4937aSGao Xiang &erofs_xattr_trusted_handler, 49547e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_SECURITY 49647e4937aSGao Xiang &erofs_xattr_security_handler, 49747e4937aSGao Xiang #endif 49847e4937aSGao Xiang NULL, 49947e4937aSGao Xiang }; 50047e4937aSGao Xiang 50147e4937aSGao Xiang struct listxattr_iter { 50247e4937aSGao Xiang struct xattr_iter it; 50347e4937aSGao Xiang 50447e4937aSGao Xiang struct dentry *dentry; 50547e4937aSGao Xiang char *buffer; 50647e4937aSGao Xiang int buffer_size, buffer_ofs; 50747e4937aSGao Xiang }; 50847e4937aSGao Xiang 50947e4937aSGao Xiang static int xattr_entrylist(struct xattr_iter *_it, 51047e4937aSGao Xiang struct erofs_xattr_entry *entry) 51147e4937aSGao Xiang { 51247e4937aSGao Xiang struct listxattr_iter *it = 51347e4937aSGao Xiang container_of(_it, struct listxattr_iter, it); 51482bc1ef4SJingbo Xu unsigned int base_index = entry->e_name_index; 51582bc1ef4SJingbo Xu unsigned int prefix_len, infix_len = 0; 51682bc1ef4SJingbo Xu const char *prefix, *infix = NULL; 51747e4937aSGao Xiang 51882bc1ef4SJingbo Xu if (entry->e_name_index & EROFS_XATTR_LONG_PREFIX) { 51982bc1ef4SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(_it->sb); 52082bc1ef4SJingbo Xu struct erofs_xattr_prefix_item *pf = sbi->xattr_prefixes + 52182bc1ef4SJingbo Xu (entry->e_name_index & EROFS_XATTR_LONG_PREFIX_MASK); 52247e4937aSGao Xiang 52382bc1ef4SJingbo Xu if (pf >= sbi->xattr_prefixes + sbi->xattr_prefix_count) 52482bc1ef4SJingbo Xu return 1; 52582bc1ef4SJingbo Xu infix = pf->prefix->infix; 52682bc1ef4SJingbo Xu infix_len = pf->infix_len; 52782bc1ef4SJingbo Xu base_index = pf->prefix->base_index; 52882bc1ef4SJingbo Xu } 52982bc1ef4SJingbo Xu 53061d325dcSLinus Torvalds prefix = erofs_xattr_prefix(base_index, it->dentry); 531a5488f29SChristian Brauner if (!prefix) 53247e4937aSGao Xiang return 1; 53347e4937aSGao Xiang prefix_len = strlen(prefix); 53447e4937aSGao Xiang 53547e4937aSGao Xiang if (!it->buffer) { 53682bc1ef4SJingbo Xu it->buffer_ofs += prefix_len + infix_len + 53782bc1ef4SJingbo Xu entry->e_name_len + 1; 53847e4937aSGao Xiang return 1; 53947e4937aSGao Xiang } 54047e4937aSGao Xiang 54182bc1ef4SJingbo Xu if (it->buffer_ofs + prefix_len + infix_len + 54247e4937aSGao Xiang + entry->e_name_len + 1 > it->buffer_size) 54347e4937aSGao Xiang return -ERANGE; 54447e4937aSGao Xiang 54547e4937aSGao Xiang memcpy(it->buffer + it->buffer_ofs, prefix, prefix_len); 54682bc1ef4SJingbo Xu memcpy(it->buffer + it->buffer_ofs + prefix_len, infix, infix_len); 54782bc1ef4SJingbo Xu it->buffer_ofs += prefix_len + infix_len; 54847e4937aSGao Xiang return 0; 54947e4937aSGao Xiang } 55047e4937aSGao Xiang 55147e4937aSGao Xiang static int xattr_namelist(struct xattr_iter *_it, 55247e4937aSGao Xiang unsigned int processed, char *buf, unsigned int len) 55347e4937aSGao Xiang { 55447e4937aSGao Xiang struct listxattr_iter *it = 55547e4937aSGao Xiang container_of(_it, struct listxattr_iter, it); 55647e4937aSGao Xiang 55747e4937aSGao Xiang memcpy(it->buffer + it->buffer_ofs, buf, len); 55847e4937aSGao Xiang it->buffer_ofs += len; 55947e4937aSGao Xiang return 0; 56047e4937aSGao Xiang } 56147e4937aSGao Xiang 56247e4937aSGao Xiang static int xattr_skipvalue(struct xattr_iter *_it, 56347e4937aSGao Xiang unsigned int value_sz) 56447e4937aSGao Xiang { 56547e4937aSGao Xiang struct listxattr_iter *it = 56647e4937aSGao Xiang container_of(_it, struct listxattr_iter, it); 56747e4937aSGao Xiang 56847e4937aSGao Xiang it->buffer[it->buffer_ofs++] = '\0'; 56947e4937aSGao Xiang return 1; 57047e4937aSGao Xiang } 57147e4937aSGao Xiang 57247e4937aSGao Xiang static const struct xattr_iter_handlers list_xattr_handlers = { 57347e4937aSGao Xiang .entry = xattr_entrylist, 57447e4937aSGao Xiang .name = xattr_namelist, 57547e4937aSGao Xiang .alloc_buffer = xattr_skipvalue, 57647e4937aSGao Xiang .value = NULL 57747e4937aSGao Xiang }; 57847e4937aSGao Xiang 57947e4937aSGao Xiang static int inline_listxattr(struct listxattr_iter *it) 58047e4937aSGao Xiang { 58147e4937aSGao Xiang int ret; 58247e4937aSGao Xiang unsigned int remaining; 58347e4937aSGao Xiang 58447e4937aSGao Xiang ret = inline_xattr_iter_begin(&it->it, d_inode(it->dentry)); 58547e4937aSGao Xiang if (ret < 0) 58647e4937aSGao Xiang return ret; 58747e4937aSGao Xiang 58847e4937aSGao Xiang remaining = ret; 58947e4937aSGao Xiang while (remaining) { 59047e4937aSGao Xiang ret = xattr_foreach(&it->it, &list_xattr_handlers, &remaining); 59147e4937aSGao Xiang if (ret) 59247e4937aSGao Xiang break; 59347e4937aSGao Xiang } 59447e4937aSGao Xiang return ret ? ret : it->buffer_ofs; 59547e4937aSGao Xiang } 59647e4937aSGao Xiang 59747e4937aSGao Xiang static int shared_listxattr(struct listxattr_iter *it) 59847e4937aSGao Xiang { 59947e4937aSGao Xiang struct inode *const inode = d_inode(it->dentry); 600a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 601399f36d8SJingbo Xu struct super_block *const sb = it->it.sb; 602399f36d8SJingbo Xu unsigned int i, xsid; 60347e4937aSGao Xiang int ret = 0; 60447e4937aSGao Xiang 60547e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 606399f36d8SJingbo Xu xsid = vi->xattr_shared_xattrs[i]; 607399f36d8SJingbo Xu it->it.blkaddr = erofs_xattr_blkaddr(sb, xsid); 608399f36d8SJingbo Xu it->it.ofs = erofs_xattr_blkoff(sb, xsid); 609*9c39ec0cSJingbo Xu it->it.kaddr = erofs_bread(&it->it.buf, it->it.blkaddr, EROFS_KMAP); 610bb88e8daSGao Xiang if (IS_ERR(it->it.kaddr)) 611bb88e8daSGao Xiang return PTR_ERR(it->it.kaddr); 61247e4937aSGao Xiang 61347e4937aSGao Xiang ret = xattr_foreach(&it->it, &list_xattr_handlers, NULL); 61447e4937aSGao Xiang if (ret) 61547e4937aSGao Xiang break; 61647e4937aSGao Xiang } 61747e4937aSGao Xiang return ret ? ret : it->buffer_ofs; 61847e4937aSGao Xiang } 61947e4937aSGao Xiang 62047e4937aSGao Xiang ssize_t erofs_listxattr(struct dentry *dentry, 62147e4937aSGao Xiang char *buffer, size_t buffer_size) 62247e4937aSGao Xiang { 62347e4937aSGao Xiang int ret; 62447e4937aSGao Xiang struct listxattr_iter it; 62547e4937aSGao Xiang 6266020ffe7SJingbo Xu ret = erofs_init_inode_xattrs(d_inode(dentry)); 627926d1650SGao Xiang if (ret == -ENOATTR) 628926d1650SGao Xiang return 0; 62947e4937aSGao Xiang if (ret) 63047e4937aSGao Xiang return ret; 63147e4937aSGao Xiang 632*9c39ec0cSJingbo Xu it.it.sb = dentry->d_sb; 633bb88e8daSGao Xiang it.it.buf = __EROFS_BUF_INITIALIZER; 634*9c39ec0cSJingbo Xu erofs_init_metabuf(&it.it.buf, it.it.sb); 63547e4937aSGao Xiang it.dentry = dentry; 63647e4937aSGao Xiang it.buffer = buffer; 63747e4937aSGao Xiang it.buffer_size = buffer_size; 63847e4937aSGao Xiang it.buffer_ofs = 0; 63947e4937aSGao Xiang 64047e4937aSGao Xiang ret = inline_listxattr(&it); 641bb88e8daSGao Xiang if (ret >= 0 || ret == -ENOATTR) 642bb88e8daSGao Xiang ret = shared_listxattr(&it); 643bb88e8daSGao Xiang erofs_put_metabuf(&it.it.buf); 64447e4937aSGao Xiang return ret; 64547e4937aSGao Xiang } 64647e4937aSGao Xiang 6479e382914SJingbo Xu void erofs_xattr_prefixes_cleanup(struct super_block *sb) 6489e382914SJingbo Xu { 6499e382914SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(sb); 6509e382914SJingbo Xu int i; 6519e382914SJingbo Xu 6529e382914SJingbo Xu if (sbi->xattr_prefixes) { 6539e382914SJingbo Xu for (i = 0; i < sbi->xattr_prefix_count; i++) 6549e382914SJingbo Xu kfree(sbi->xattr_prefixes[i].prefix); 6559e382914SJingbo Xu kfree(sbi->xattr_prefixes); 6569e382914SJingbo Xu sbi->xattr_prefixes = NULL; 6579e382914SJingbo Xu } 6589e382914SJingbo Xu } 6599e382914SJingbo Xu 6609e382914SJingbo Xu int erofs_xattr_prefixes_init(struct super_block *sb) 6619e382914SJingbo Xu { 6629e382914SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(sb); 6639e382914SJingbo Xu struct erofs_buf buf = __EROFS_BUF_INITIALIZER; 6649e382914SJingbo Xu erofs_off_t pos = (erofs_off_t)sbi->xattr_prefix_start << 2; 6659e382914SJingbo Xu struct erofs_xattr_prefix_item *pfs; 6669e382914SJingbo Xu int ret = 0, i, len; 6679e382914SJingbo Xu 6689e382914SJingbo Xu if (!sbi->xattr_prefix_count) 6699e382914SJingbo Xu return 0; 6709e382914SJingbo Xu 6719e382914SJingbo Xu pfs = kzalloc(sbi->xattr_prefix_count * sizeof(*pfs), GFP_KERNEL); 6729e382914SJingbo Xu if (!pfs) 6739e382914SJingbo Xu return -ENOMEM; 6749e382914SJingbo Xu 6750a17567bSJingbo Xu if (sbi->packed_inode) 6769e382914SJingbo Xu buf.inode = sbi->packed_inode; 6779e382914SJingbo Xu else 6789e382914SJingbo Xu erofs_init_metabuf(&buf, sb); 6799e382914SJingbo Xu 6809e382914SJingbo Xu for (i = 0; i < sbi->xattr_prefix_count; i++) { 6819e382914SJingbo Xu void *ptr = erofs_read_metadata(sb, &buf, &pos, &len); 6829e382914SJingbo Xu 6839e382914SJingbo Xu if (IS_ERR(ptr)) { 6849e382914SJingbo Xu ret = PTR_ERR(ptr); 6859e382914SJingbo Xu break; 6869e382914SJingbo Xu } else if (len < sizeof(*pfs->prefix) || 6879e382914SJingbo Xu len > EROFS_NAME_LEN + sizeof(*pfs->prefix)) { 6889e382914SJingbo Xu kfree(ptr); 6899e382914SJingbo Xu ret = -EFSCORRUPTED; 6909e382914SJingbo Xu break; 6919e382914SJingbo Xu } 6929e382914SJingbo Xu pfs[i].prefix = ptr; 6939e382914SJingbo Xu pfs[i].infix_len = len - sizeof(struct erofs_xattr_long_prefix); 6949e382914SJingbo Xu } 6959e382914SJingbo Xu 6969e382914SJingbo Xu erofs_put_metabuf(&buf); 6979e382914SJingbo Xu sbi->xattr_prefixes = pfs; 6989e382914SJingbo Xu if (ret) 6999e382914SJingbo Xu erofs_xattr_prefixes_cleanup(sb); 7009e382914SJingbo Xu return ret; 7019e382914SJingbo Xu } 7029e382914SJingbo Xu 70347e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_POSIX_ACL 7040cad6246SMiklos Szeredi struct posix_acl *erofs_get_acl(struct inode *inode, int type, bool rcu) 70547e4937aSGao Xiang { 70647e4937aSGao Xiang struct posix_acl *acl; 70747e4937aSGao Xiang int prefix, rc; 70847e4937aSGao Xiang char *value = NULL; 70947e4937aSGao Xiang 7100cad6246SMiklos Szeredi if (rcu) 7110cad6246SMiklos Szeredi return ERR_PTR(-ECHILD); 7120cad6246SMiklos Szeredi 71347e4937aSGao Xiang switch (type) { 71447e4937aSGao Xiang case ACL_TYPE_ACCESS: 71547e4937aSGao Xiang prefix = EROFS_XATTR_INDEX_POSIX_ACL_ACCESS; 71647e4937aSGao Xiang break; 71747e4937aSGao Xiang case ACL_TYPE_DEFAULT: 71847e4937aSGao Xiang prefix = EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT; 71947e4937aSGao Xiang break; 72047e4937aSGao Xiang default: 72147e4937aSGao Xiang return ERR_PTR(-EINVAL); 72247e4937aSGao Xiang } 72347e4937aSGao Xiang 72447e4937aSGao Xiang rc = erofs_getxattr(inode, prefix, "", NULL, 0); 72547e4937aSGao Xiang if (rc > 0) { 72647e4937aSGao Xiang value = kmalloc(rc, GFP_KERNEL); 72747e4937aSGao Xiang if (!value) 72847e4937aSGao Xiang return ERR_PTR(-ENOMEM); 72947e4937aSGao Xiang rc = erofs_getxattr(inode, prefix, "", value, rc); 73047e4937aSGao Xiang } 73147e4937aSGao Xiang 73247e4937aSGao Xiang if (rc == -ENOATTR) 73347e4937aSGao Xiang acl = NULL; 73447e4937aSGao Xiang else if (rc < 0) 73547e4937aSGao Xiang acl = ERR_PTR(rc); 73647e4937aSGao Xiang else 73747e4937aSGao Xiang acl = posix_acl_from_xattr(&init_user_ns, value, rc); 73847e4937aSGao Xiang kfree(value); 73947e4937aSGao Xiang return acl; 74047e4937aSGao Xiang } 74147e4937aSGao Xiang #endif 742