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; 843acea5fcSJingbo Xu it.blkaddr = erofs_blknr(sb, erofs_iloc(inode) + vi->inode_isize); 853acea5fcSJingbo Xu it.ofs = erofs_blkoff(sb, erofs_iloc(inode) + vi->inode_isize); 8647e4937aSGao Xiang 87bb88e8daSGao Xiang /* read in shared xattr array (non-atomic, see kmalloc below) */ 88bb88e8daSGao Xiang it.kaddr = erofs_read_metabuf(&it.buf, sb, it.blkaddr, EROFS_KMAP); 89bb88e8daSGao Xiang if (IS_ERR(it.kaddr)) { 90bb88e8daSGao Xiang ret = PTR_ERR(it.kaddr); 9147e4937aSGao Xiang goto out_unlock; 9247e4937aSGao Xiang } 9347e4937aSGao Xiang 9447e4937aSGao Xiang ih = (struct erofs_xattr_ibody_header *)(it.kaddr + it.ofs); 9547e4937aSGao Xiang vi->xattr_shared_count = ih->h_shared_count; 9647e4937aSGao Xiang vi->xattr_shared_xattrs = kmalloc_array(vi->xattr_shared_count, 9747e4937aSGao Xiang sizeof(uint), GFP_KERNEL); 9847e4937aSGao Xiang if (!vi->xattr_shared_xattrs) { 99bb88e8daSGao Xiang erofs_put_metabuf(&it.buf); 10047e4937aSGao Xiang ret = -ENOMEM; 10147e4937aSGao Xiang goto out_unlock; 10247e4937aSGao Xiang } 10347e4937aSGao Xiang 10447e4937aSGao Xiang /* let's skip ibody header */ 10547e4937aSGao Xiang it.ofs += sizeof(struct erofs_xattr_ibody_header); 10647e4937aSGao Xiang 10747e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 1083acea5fcSJingbo Xu if (it.ofs >= sb->s_blocksize) { 10947e4937aSGao Xiang /* cannot be unaligned */ 1103acea5fcSJingbo Xu DBG_BUGON(it.ofs != sb->s_blocksize); 11147e4937aSGao Xiang 112bb88e8daSGao Xiang it.kaddr = erofs_read_metabuf(&it.buf, sb, ++it.blkaddr, 113bb88e8daSGao Xiang 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); 159bb88e8daSGao Xiang it->kaddr = erofs_read_metabuf(&it->buf, it->sb, it->blkaddr, 160927e5010SGao Xiang EROFS_KMAP); 161bb88e8daSGao Xiang if (IS_ERR(it->kaddr)) 162bb88e8daSGao Xiang return PTR_ERR(it->kaddr); 1633acea5fcSJingbo Xu it->ofs = erofs_blkoff(it->sb, it->ofs); 16447e4937aSGao Xiang return 0; 16547e4937aSGao Xiang } 16647e4937aSGao Xiang 16747e4937aSGao Xiang static int inline_xattr_iter_begin(struct xattr_iter *it, 16847e4937aSGao Xiang struct inode *inode) 16947e4937aSGao Xiang { 170a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 17147e4937aSGao Xiang unsigned int xattr_header_sz, inline_xattr_ofs; 17247e4937aSGao Xiang 173399f36d8SJingbo Xu xattr_header_sz = sizeof(struct erofs_xattr_ibody_header) + 174399f36d8SJingbo Xu sizeof(u32) * vi->xattr_shared_count; 1758d8a09b0SGao Xiang if (xattr_header_sz >= vi->xattr_isize) { 17647e4937aSGao Xiang DBG_BUGON(xattr_header_sz > vi->xattr_isize); 17747e4937aSGao Xiang return -ENOATTR; 17847e4937aSGao Xiang } 17947e4937aSGao Xiang 18047e4937aSGao Xiang inline_xattr_ofs = vi->inode_isize + xattr_header_sz; 18147e4937aSGao Xiang 1823acea5fcSJingbo Xu it->blkaddr = erofs_blknr(it->sb, erofs_iloc(inode) + inline_xattr_ofs); 1833acea5fcSJingbo Xu it->ofs = erofs_blkoff(it->sb, erofs_iloc(inode) + inline_xattr_ofs); 184bb88e8daSGao Xiang it->kaddr = erofs_read_metabuf(&it->buf, inode->i_sb, it->blkaddr, 185927e5010SGao Xiang EROFS_KMAP); 186bb88e8daSGao Xiang if (IS_ERR(it->kaddr)) 187bb88e8daSGao Xiang return PTR_ERR(it->kaddr); 18847e4937aSGao Xiang return vi->xattr_isize - xattr_header_sz; 18947e4937aSGao Xiang } 19047e4937aSGao Xiang 19147e4937aSGao Xiang /* 19247e4937aSGao Xiang * Regardless of success or failure, `xattr_foreach' will end up with 19347e4937aSGao Xiang * `ofs' pointing to the next xattr item rather than an arbitrary position. 19447e4937aSGao Xiang */ 19547e4937aSGao Xiang static int xattr_foreach(struct xattr_iter *it, 19647e4937aSGao Xiang const struct xattr_iter_handlers *op, 19747e4937aSGao Xiang unsigned int *tlimit) 19847e4937aSGao Xiang { 19947e4937aSGao Xiang struct erofs_xattr_entry entry; 20047e4937aSGao Xiang unsigned int value_sz, processed, slice; 20147e4937aSGao Xiang int err; 20247e4937aSGao Xiang 20347e4937aSGao Xiang /* 0. fixup blkaddr, ofs, ipage */ 20447e4937aSGao Xiang err = xattr_iter_fixup(it); 20547e4937aSGao Xiang if (err) 20647e4937aSGao Xiang return err; 20747e4937aSGao Xiang 20847e4937aSGao Xiang /* 20947e4937aSGao Xiang * 1. read xattr entry to the memory, 21047e4937aSGao Xiang * since we do EROFS_XATTR_ALIGN 21147e4937aSGao Xiang * therefore entry should be in the page 21247e4937aSGao Xiang */ 21347e4937aSGao Xiang entry = *(struct erofs_xattr_entry *)(it->kaddr + it->ofs); 21447e4937aSGao Xiang if (tlimit) { 215b6796abdSGao Xiang unsigned int entry_sz = erofs_xattr_entry_size(&entry); 21647e4937aSGao Xiang 21747e4937aSGao Xiang /* xattr on-disk corruption: xattr entry beyond xattr_isize */ 2188d8a09b0SGao Xiang if (*tlimit < entry_sz) { 21947e4937aSGao Xiang DBG_BUGON(1); 22047e4937aSGao Xiang return -EFSCORRUPTED; 22147e4937aSGao Xiang } 22247e4937aSGao Xiang *tlimit -= entry_sz; 22347e4937aSGao Xiang } 22447e4937aSGao Xiang 22547e4937aSGao Xiang it->ofs += sizeof(struct erofs_xattr_entry); 22647e4937aSGao Xiang value_sz = le16_to_cpu(entry.e_value_size); 22747e4937aSGao Xiang 22847e4937aSGao Xiang /* handle entry */ 22947e4937aSGao Xiang err = op->entry(it, &entry); 23047e4937aSGao Xiang if (err) { 23147e4937aSGao Xiang it->ofs += entry.e_name_len + value_sz; 23247e4937aSGao Xiang goto out; 23347e4937aSGao Xiang } 23447e4937aSGao Xiang 23547e4937aSGao Xiang /* 2. handle xattr name (ofs will finally be at the end of name) */ 23647e4937aSGao Xiang processed = 0; 23747e4937aSGao Xiang 23847e4937aSGao Xiang while (processed < entry.e_name_len) { 2393acea5fcSJingbo Xu if (it->ofs >= it->sb->s_blocksize) { 2403acea5fcSJingbo Xu DBG_BUGON(it->ofs > it->sb->s_blocksize); 24147e4937aSGao Xiang 24247e4937aSGao Xiang err = xattr_iter_fixup(it); 24347e4937aSGao Xiang if (err) 24447e4937aSGao Xiang goto out; 24547e4937aSGao Xiang it->ofs = 0; 24647e4937aSGao Xiang } 24747e4937aSGao Xiang 2483acea5fcSJingbo Xu slice = min_t(unsigned int, it->sb->s_blocksize - it->ofs, 24947e4937aSGao Xiang entry.e_name_len - processed); 25047e4937aSGao Xiang 25147e4937aSGao Xiang /* handle name */ 25247e4937aSGao Xiang err = op->name(it, processed, it->kaddr + it->ofs, slice); 25347e4937aSGao Xiang if (err) { 25447e4937aSGao Xiang it->ofs += entry.e_name_len - processed + value_sz; 25547e4937aSGao Xiang goto out; 25647e4937aSGao Xiang } 25747e4937aSGao Xiang 25847e4937aSGao Xiang it->ofs += slice; 25947e4937aSGao Xiang processed += slice; 26047e4937aSGao Xiang } 26147e4937aSGao Xiang 26247e4937aSGao Xiang /* 3. handle xattr value */ 26347e4937aSGao Xiang processed = 0; 26447e4937aSGao Xiang 26547e4937aSGao Xiang if (op->alloc_buffer) { 26647e4937aSGao Xiang err = op->alloc_buffer(it, value_sz); 26747e4937aSGao Xiang if (err) { 26847e4937aSGao Xiang it->ofs += value_sz; 26947e4937aSGao Xiang goto out; 27047e4937aSGao Xiang } 27147e4937aSGao Xiang } 27247e4937aSGao Xiang 27347e4937aSGao Xiang while (processed < value_sz) { 2743acea5fcSJingbo Xu if (it->ofs >= it->sb->s_blocksize) { 2753acea5fcSJingbo Xu DBG_BUGON(it->ofs > it->sb->s_blocksize); 27647e4937aSGao Xiang 27747e4937aSGao Xiang err = xattr_iter_fixup(it); 27847e4937aSGao Xiang if (err) 27947e4937aSGao Xiang goto out; 28047e4937aSGao Xiang it->ofs = 0; 28147e4937aSGao Xiang } 28247e4937aSGao Xiang 2833acea5fcSJingbo Xu slice = min_t(unsigned int, it->sb->s_blocksize - it->ofs, 28447e4937aSGao Xiang value_sz - processed); 28547e4937aSGao Xiang op->value(it, processed, it->kaddr + it->ofs, slice); 28647e4937aSGao Xiang it->ofs += slice; 28747e4937aSGao Xiang processed += slice; 28847e4937aSGao Xiang } 28947e4937aSGao Xiang 29047e4937aSGao Xiang out: 29147e4937aSGao Xiang /* xattrs should be 4-byte aligned (on-disk constraint) */ 29247e4937aSGao Xiang it->ofs = EROFS_XATTR_ALIGN(it->ofs); 29347e4937aSGao Xiang return err < 0 ? err : 0; 29447e4937aSGao Xiang } 29547e4937aSGao Xiang 29647e4937aSGao Xiang struct getxattr_iter { 29747e4937aSGao Xiang struct xattr_iter it; 29847e4937aSGao Xiang 29947e4937aSGao Xiang char *buffer; 30047e4937aSGao Xiang int buffer_size, index; 30147e4937aSGao Xiang struct qstr name; 30247e4937aSGao Xiang }; 30347e4937aSGao Xiang 30447e4937aSGao Xiang static int xattr_entrymatch(struct xattr_iter *_it, 30547e4937aSGao Xiang struct erofs_xattr_entry *entry) 30647e4937aSGao Xiang { 30747e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 30847e4937aSGao Xiang 30947e4937aSGao Xiang return (it->index != entry->e_name_index || 31047e4937aSGao Xiang it->name.len != entry->e_name_len) ? -ENOATTR : 0; 31147e4937aSGao Xiang } 31247e4937aSGao Xiang 31347e4937aSGao Xiang static int xattr_namematch(struct xattr_iter *_it, 31447e4937aSGao Xiang unsigned int processed, char *buf, unsigned int len) 31547e4937aSGao Xiang { 31647e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 31747e4937aSGao Xiang 31847e4937aSGao Xiang return memcmp(buf, it->name.name + processed, len) ? -ENOATTR : 0; 31947e4937aSGao Xiang } 32047e4937aSGao Xiang 32147e4937aSGao Xiang static int xattr_checkbuffer(struct xattr_iter *_it, 32247e4937aSGao Xiang unsigned int value_sz) 32347e4937aSGao Xiang { 32447e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 32547e4937aSGao Xiang int err = it->buffer_size < value_sz ? -ERANGE : 0; 32647e4937aSGao Xiang 32747e4937aSGao Xiang it->buffer_size = value_sz; 32847e4937aSGao Xiang return !it->buffer ? 1 : err; 32947e4937aSGao Xiang } 33047e4937aSGao Xiang 33147e4937aSGao Xiang static void xattr_copyvalue(struct xattr_iter *_it, 33247e4937aSGao Xiang unsigned int processed, 33347e4937aSGao Xiang char *buf, unsigned int len) 33447e4937aSGao Xiang { 33547e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 33647e4937aSGao Xiang 33747e4937aSGao Xiang memcpy(it->buffer + processed, buf, len); 33847e4937aSGao Xiang } 33947e4937aSGao Xiang 34047e4937aSGao Xiang static const struct xattr_iter_handlers find_xattr_handlers = { 34147e4937aSGao Xiang .entry = xattr_entrymatch, 34247e4937aSGao Xiang .name = xattr_namematch, 34347e4937aSGao Xiang .alloc_buffer = xattr_checkbuffer, 34447e4937aSGao Xiang .value = xattr_copyvalue 34547e4937aSGao Xiang }; 34647e4937aSGao Xiang 34747e4937aSGao Xiang static int inline_getxattr(struct inode *inode, struct getxattr_iter *it) 34847e4937aSGao Xiang { 34947e4937aSGao Xiang int ret; 35047e4937aSGao Xiang unsigned int remaining; 35147e4937aSGao Xiang 35247e4937aSGao Xiang ret = inline_xattr_iter_begin(&it->it, inode); 35347e4937aSGao Xiang if (ret < 0) 35447e4937aSGao Xiang return ret; 35547e4937aSGao Xiang 35647e4937aSGao Xiang remaining = ret; 35747e4937aSGao Xiang while (remaining) { 35847e4937aSGao Xiang ret = xattr_foreach(&it->it, &find_xattr_handlers, &remaining); 35947e4937aSGao Xiang if (ret != -ENOATTR) 36047e4937aSGao Xiang break; 36147e4937aSGao Xiang } 36247e4937aSGao Xiang return ret ? ret : it->buffer_size; 36347e4937aSGao Xiang } 36447e4937aSGao Xiang 36547e4937aSGao Xiang static int shared_getxattr(struct inode *inode, struct getxattr_iter *it) 36647e4937aSGao Xiang { 367a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 368399f36d8SJingbo Xu struct super_block *const sb = it->it.sb; 369399f36d8SJingbo Xu unsigned int i, xsid; 37047e4937aSGao Xiang int ret = -ENOATTR; 37147e4937aSGao Xiang 37247e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 373399f36d8SJingbo Xu xsid = vi->xattr_shared_xattrs[i]; 374399f36d8SJingbo Xu it->it.blkaddr = erofs_xattr_blkaddr(sb, xsid); 375399f36d8SJingbo Xu it->it.ofs = erofs_xattr_blkoff(sb, xsid); 376399f36d8SJingbo Xu it->it.kaddr = erofs_read_metabuf(&it->it.buf, sb, 377399f36d8SJingbo Xu it->it.blkaddr, EROFS_KMAP); 378bb88e8daSGao Xiang if (IS_ERR(it->it.kaddr)) 379bb88e8daSGao Xiang return PTR_ERR(it->it.kaddr); 38047e4937aSGao Xiang 38147e4937aSGao Xiang ret = xattr_foreach(&it->it, &find_xattr_handlers, NULL); 38247e4937aSGao Xiang if (ret != -ENOATTR) 38347e4937aSGao Xiang break; 38447e4937aSGao Xiang } 38547e4937aSGao Xiang return ret ? ret : it->buffer_size; 38647e4937aSGao Xiang } 38747e4937aSGao Xiang 38847e4937aSGao Xiang static bool erofs_xattr_user_list(struct dentry *dentry) 38947e4937aSGao Xiang { 390e6242465SGao Xiang return test_opt(&EROFS_SB(dentry->d_sb)->opt, XATTR_USER); 39147e4937aSGao Xiang } 39247e4937aSGao Xiang 39347e4937aSGao Xiang static bool erofs_xattr_trusted_list(struct dentry *dentry) 39447e4937aSGao Xiang { 39547e4937aSGao Xiang return capable(CAP_SYS_ADMIN); 39647e4937aSGao Xiang } 39747e4937aSGao Xiang 39847e4937aSGao Xiang int erofs_getxattr(struct inode *inode, int index, 39947e4937aSGao Xiang const char *name, 40047e4937aSGao Xiang void *buffer, size_t buffer_size) 40147e4937aSGao Xiang { 40247e4937aSGao Xiang int ret; 40347e4937aSGao Xiang struct getxattr_iter it; 40447e4937aSGao Xiang 4058d8a09b0SGao Xiang if (!name) 40647e4937aSGao Xiang return -EINVAL; 40747e4937aSGao Xiang 4086020ffe7SJingbo Xu ret = erofs_init_inode_xattrs(inode); 40947e4937aSGao Xiang if (ret) 41047e4937aSGao Xiang return ret; 41147e4937aSGao Xiang 41247e4937aSGao Xiang it.index = index; 41347e4937aSGao Xiang it.name.len = strlen(name); 41447e4937aSGao Xiang if (it.name.len > EROFS_NAME_LEN) 41547e4937aSGao Xiang return -ERANGE; 416bb88e8daSGao Xiang 417bb88e8daSGao Xiang it.it.buf = __EROFS_BUF_INITIALIZER; 41847e4937aSGao Xiang it.name.name = name; 41947e4937aSGao Xiang 42047e4937aSGao Xiang it.buffer = buffer; 42147e4937aSGao Xiang it.buffer_size = buffer_size; 42247e4937aSGao Xiang 42347e4937aSGao Xiang it.it.sb = inode->i_sb; 42447e4937aSGao Xiang ret = inline_getxattr(inode, &it); 42547e4937aSGao Xiang if (ret == -ENOATTR) 42647e4937aSGao Xiang ret = shared_getxattr(inode, &it); 427bb88e8daSGao Xiang erofs_put_metabuf(&it.it.buf); 42847e4937aSGao Xiang return ret; 42947e4937aSGao Xiang } 43047e4937aSGao Xiang 43147e4937aSGao Xiang static int erofs_xattr_generic_get(const struct xattr_handler *handler, 43247e4937aSGao Xiang struct dentry *unused, struct inode *inode, 43347e4937aSGao Xiang const char *name, void *buffer, size_t size) 43447e4937aSGao Xiang { 435b05f30bcSJingbo Xu if (handler->flags == EROFS_XATTR_INDEX_USER && 436b05f30bcSJingbo Xu !test_opt(&EROFS_I_SB(inode)->opt, XATTR_USER)) 43747e4937aSGao Xiang return -EOPNOTSUPP; 43847e4937aSGao Xiang 43947e4937aSGao Xiang return erofs_getxattr(inode, handler->flags, name, buffer, size); 44047e4937aSGao Xiang } 44147e4937aSGao Xiang 44247e4937aSGao Xiang const struct xattr_handler erofs_xattr_user_handler = { 44347e4937aSGao Xiang .prefix = XATTR_USER_PREFIX, 44447e4937aSGao Xiang .flags = EROFS_XATTR_INDEX_USER, 44547e4937aSGao Xiang .list = erofs_xattr_user_list, 44647e4937aSGao Xiang .get = erofs_xattr_generic_get, 44747e4937aSGao Xiang }; 44847e4937aSGao Xiang 44947e4937aSGao Xiang const struct xattr_handler erofs_xattr_trusted_handler = { 45047e4937aSGao Xiang .prefix = XATTR_TRUSTED_PREFIX, 45147e4937aSGao Xiang .flags = EROFS_XATTR_INDEX_TRUSTED, 45247e4937aSGao Xiang .list = erofs_xattr_trusted_list, 45347e4937aSGao Xiang .get = erofs_xattr_generic_get, 45447e4937aSGao Xiang }; 45547e4937aSGao Xiang 45647e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_SECURITY 45747e4937aSGao Xiang const struct xattr_handler __maybe_unused erofs_xattr_security_handler = { 45847e4937aSGao Xiang .prefix = XATTR_SECURITY_PREFIX, 45947e4937aSGao Xiang .flags = EROFS_XATTR_INDEX_SECURITY, 46047e4937aSGao Xiang .get = erofs_xattr_generic_get, 46147e4937aSGao Xiang }; 46247e4937aSGao Xiang #endif 46347e4937aSGao Xiang 46447e4937aSGao Xiang const struct xattr_handler *erofs_xattr_handlers[] = { 46547e4937aSGao Xiang &erofs_xattr_user_handler, 46647e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_POSIX_ACL 46747e4937aSGao Xiang &posix_acl_access_xattr_handler, 46847e4937aSGao Xiang &posix_acl_default_xattr_handler, 46947e4937aSGao Xiang #endif 47047e4937aSGao Xiang &erofs_xattr_trusted_handler, 47147e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_SECURITY 47247e4937aSGao Xiang &erofs_xattr_security_handler, 47347e4937aSGao Xiang #endif 47447e4937aSGao Xiang NULL, 47547e4937aSGao Xiang }; 47647e4937aSGao Xiang 47747e4937aSGao Xiang struct listxattr_iter { 47847e4937aSGao Xiang struct xattr_iter it; 47947e4937aSGao Xiang 48047e4937aSGao Xiang struct dentry *dentry; 48147e4937aSGao Xiang char *buffer; 48247e4937aSGao Xiang int buffer_size, buffer_ofs; 48347e4937aSGao Xiang }; 48447e4937aSGao Xiang 48547e4937aSGao Xiang static int xattr_entrylist(struct xattr_iter *_it, 48647e4937aSGao Xiang struct erofs_xattr_entry *entry) 48747e4937aSGao Xiang { 48847e4937aSGao Xiang struct listxattr_iter *it = 48947e4937aSGao Xiang container_of(_it, struct listxattr_iter, it); 49047e4937aSGao Xiang unsigned int prefix_len; 49147e4937aSGao Xiang const char *prefix; 49247e4937aSGao Xiang 49347e4937aSGao Xiang const struct xattr_handler *h = 49447e4937aSGao Xiang erofs_xattr_handler(entry->e_name_index); 49547e4937aSGao Xiang 49647e4937aSGao Xiang if (!h || (h->list && !h->list(it->dentry))) 49747e4937aSGao Xiang return 1; 49847e4937aSGao Xiang 49947e4937aSGao Xiang prefix = xattr_prefix(h); 50047e4937aSGao Xiang prefix_len = strlen(prefix); 50147e4937aSGao Xiang 50247e4937aSGao Xiang if (!it->buffer) { 50347e4937aSGao Xiang it->buffer_ofs += prefix_len + entry->e_name_len + 1; 50447e4937aSGao Xiang return 1; 50547e4937aSGao Xiang } 50647e4937aSGao Xiang 50747e4937aSGao Xiang if (it->buffer_ofs + prefix_len 50847e4937aSGao Xiang + entry->e_name_len + 1 > it->buffer_size) 50947e4937aSGao Xiang return -ERANGE; 51047e4937aSGao Xiang 51147e4937aSGao Xiang memcpy(it->buffer + it->buffer_ofs, prefix, prefix_len); 51247e4937aSGao Xiang it->buffer_ofs += prefix_len; 51347e4937aSGao Xiang return 0; 51447e4937aSGao Xiang } 51547e4937aSGao Xiang 51647e4937aSGao Xiang static int xattr_namelist(struct xattr_iter *_it, 51747e4937aSGao Xiang unsigned int processed, char *buf, unsigned int len) 51847e4937aSGao Xiang { 51947e4937aSGao Xiang struct listxattr_iter *it = 52047e4937aSGao Xiang container_of(_it, struct listxattr_iter, it); 52147e4937aSGao Xiang 52247e4937aSGao Xiang memcpy(it->buffer + it->buffer_ofs, buf, len); 52347e4937aSGao Xiang it->buffer_ofs += len; 52447e4937aSGao Xiang return 0; 52547e4937aSGao Xiang } 52647e4937aSGao Xiang 52747e4937aSGao Xiang static int xattr_skipvalue(struct xattr_iter *_it, 52847e4937aSGao Xiang unsigned int value_sz) 52947e4937aSGao Xiang { 53047e4937aSGao Xiang struct listxattr_iter *it = 53147e4937aSGao Xiang container_of(_it, struct listxattr_iter, it); 53247e4937aSGao Xiang 53347e4937aSGao Xiang it->buffer[it->buffer_ofs++] = '\0'; 53447e4937aSGao Xiang return 1; 53547e4937aSGao Xiang } 53647e4937aSGao Xiang 53747e4937aSGao Xiang static const struct xattr_iter_handlers list_xattr_handlers = { 53847e4937aSGao Xiang .entry = xattr_entrylist, 53947e4937aSGao Xiang .name = xattr_namelist, 54047e4937aSGao Xiang .alloc_buffer = xattr_skipvalue, 54147e4937aSGao Xiang .value = NULL 54247e4937aSGao Xiang }; 54347e4937aSGao Xiang 54447e4937aSGao Xiang static int inline_listxattr(struct listxattr_iter *it) 54547e4937aSGao Xiang { 54647e4937aSGao Xiang int ret; 54747e4937aSGao Xiang unsigned int remaining; 54847e4937aSGao Xiang 54947e4937aSGao Xiang ret = inline_xattr_iter_begin(&it->it, d_inode(it->dentry)); 55047e4937aSGao Xiang if (ret < 0) 55147e4937aSGao Xiang return ret; 55247e4937aSGao Xiang 55347e4937aSGao Xiang remaining = ret; 55447e4937aSGao Xiang while (remaining) { 55547e4937aSGao Xiang ret = xattr_foreach(&it->it, &list_xattr_handlers, &remaining); 55647e4937aSGao Xiang if (ret) 55747e4937aSGao Xiang break; 55847e4937aSGao Xiang } 55947e4937aSGao Xiang return ret ? ret : it->buffer_ofs; 56047e4937aSGao Xiang } 56147e4937aSGao Xiang 56247e4937aSGao Xiang static int shared_listxattr(struct listxattr_iter *it) 56347e4937aSGao Xiang { 56447e4937aSGao Xiang struct inode *const inode = d_inode(it->dentry); 565a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 566399f36d8SJingbo Xu struct super_block *const sb = it->it.sb; 567399f36d8SJingbo Xu unsigned int i, xsid; 56847e4937aSGao Xiang int ret = 0; 56947e4937aSGao Xiang 57047e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 571399f36d8SJingbo Xu xsid = vi->xattr_shared_xattrs[i]; 572399f36d8SJingbo Xu it->it.blkaddr = erofs_xattr_blkaddr(sb, xsid); 573399f36d8SJingbo Xu it->it.ofs = erofs_xattr_blkoff(sb, xsid); 574399f36d8SJingbo Xu it->it.kaddr = erofs_read_metabuf(&it->it.buf, sb, 575399f36d8SJingbo Xu it->it.blkaddr, EROFS_KMAP); 576bb88e8daSGao Xiang if (IS_ERR(it->it.kaddr)) 577bb88e8daSGao Xiang return PTR_ERR(it->it.kaddr); 57847e4937aSGao Xiang 57947e4937aSGao Xiang ret = xattr_foreach(&it->it, &list_xattr_handlers, NULL); 58047e4937aSGao Xiang if (ret) 58147e4937aSGao Xiang break; 58247e4937aSGao Xiang } 58347e4937aSGao Xiang return ret ? ret : it->buffer_ofs; 58447e4937aSGao Xiang } 58547e4937aSGao Xiang 58647e4937aSGao Xiang ssize_t erofs_listxattr(struct dentry *dentry, 58747e4937aSGao Xiang char *buffer, size_t buffer_size) 58847e4937aSGao Xiang { 58947e4937aSGao Xiang int ret; 59047e4937aSGao Xiang struct listxattr_iter it; 59147e4937aSGao Xiang 5926020ffe7SJingbo Xu ret = erofs_init_inode_xattrs(d_inode(dentry)); 593926d1650SGao Xiang if (ret == -ENOATTR) 594926d1650SGao Xiang return 0; 59547e4937aSGao Xiang if (ret) 59647e4937aSGao Xiang return ret; 59747e4937aSGao Xiang 598bb88e8daSGao Xiang it.it.buf = __EROFS_BUF_INITIALIZER; 59947e4937aSGao Xiang it.dentry = dentry; 60047e4937aSGao Xiang it.buffer = buffer; 60147e4937aSGao Xiang it.buffer_size = buffer_size; 60247e4937aSGao Xiang it.buffer_ofs = 0; 60347e4937aSGao Xiang 60447e4937aSGao Xiang it.it.sb = dentry->d_sb; 60547e4937aSGao Xiang 60647e4937aSGao Xiang ret = inline_listxattr(&it); 607bb88e8daSGao Xiang if (ret >= 0 || ret == -ENOATTR) 608bb88e8daSGao Xiang ret = shared_listxattr(&it); 609bb88e8daSGao Xiang erofs_put_metabuf(&it.it.buf); 61047e4937aSGao Xiang return ret; 61147e4937aSGao Xiang } 61247e4937aSGao Xiang 613*9e382914SJingbo Xu void erofs_xattr_prefixes_cleanup(struct super_block *sb) 614*9e382914SJingbo Xu { 615*9e382914SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(sb); 616*9e382914SJingbo Xu int i; 617*9e382914SJingbo Xu 618*9e382914SJingbo Xu if (sbi->xattr_prefixes) { 619*9e382914SJingbo Xu for (i = 0; i < sbi->xattr_prefix_count; i++) 620*9e382914SJingbo Xu kfree(sbi->xattr_prefixes[i].prefix); 621*9e382914SJingbo Xu kfree(sbi->xattr_prefixes); 622*9e382914SJingbo Xu sbi->xattr_prefixes = NULL; 623*9e382914SJingbo Xu } 624*9e382914SJingbo Xu } 625*9e382914SJingbo Xu 626*9e382914SJingbo Xu int erofs_xattr_prefixes_init(struct super_block *sb) 627*9e382914SJingbo Xu { 628*9e382914SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(sb); 629*9e382914SJingbo Xu struct erofs_buf buf = __EROFS_BUF_INITIALIZER; 630*9e382914SJingbo Xu erofs_off_t pos = (erofs_off_t)sbi->xattr_prefix_start << 2; 631*9e382914SJingbo Xu struct erofs_xattr_prefix_item *pfs; 632*9e382914SJingbo Xu int ret = 0, i, len; 633*9e382914SJingbo Xu 634*9e382914SJingbo Xu if (!sbi->xattr_prefix_count) 635*9e382914SJingbo Xu return 0; 636*9e382914SJingbo Xu 637*9e382914SJingbo Xu pfs = kzalloc(sbi->xattr_prefix_count * sizeof(*pfs), GFP_KERNEL); 638*9e382914SJingbo Xu if (!pfs) 639*9e382914SJingbo Xu return -ENOMEM; 640*9e382914SJingbo Xu 641*9e382914SJingbo Xu if (erofs_sb_has_fragments(sbi)) 642*9e382914SJingbo Xu buf.inode = sbi->packed_inode; 643*9e382914SJingbo Xu else 644*9e382914SJingbo Xu erofs_init_metabuf(&buf, sb); 645*9e382914SJingbo Xu 646*9e382914SJingbo Xu for (i = 0; i < sbi->xattr_prefix_count; i++) { 647*9e382914SJingbo Xu void *ptr = erofs_read_metadata(sb, &buf, &pos, &len); 648*9e382914SJingbo Xu 649*9e382914SJingbo Xu if (IS_ERR(ptr)) { 650*9e382914SJingbo Xu ret = PTR_ERR(ptr); 651*9e382914SJingbo Xu break; 652*9e382914SJingbo Xu } else if (len < sizeof(*pfs->prefix) || 653*9e382914SJingbo Xu len > EROFS_NAME_LEN + sizeof(*pfs->prefix)) { 654*9e382914SJingbo Xu kfree(ptr); 655*9e382914SJingbo Xu ret = -EFSCORRUPTED; 656*9e382914SJingbo Xu break; 657*9e382914SJingbo Xu } 658*9e382914SJingbo Xu pfs[i].prefix = ptr; 659*9e382914SJingbo Xu pfs[i].infix_len = len - sizeof(struct erofs_xattr_long_prefix); 660*9e382914SJingbo Xu } 661*9e382914SJingbo Xu 662*9e382914SJingbo Xu erofs_put_metabuf(&buf); 663*9e382914SJingbo Xu sbi->xattr_prefixes = pfs; 664*9e382914SJingbo Xu if (ret) 665*9e382914SJingbo Xu erofs_xattr_prefixes_cleanup(sb); 666*9e382914SJingbo Xu return ret; 667*9e382914SJingbo Xu } 668*9e382914SJingbo Xu 66947e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_POSIX_ACL 6700cad6246SMiklos Szeredi struct posix_acl *erofs_get_acl(struct inode *inode, int type, bool rcu) 67147e4937aSGao Xiang { 67247e4937aSGao Xiang struct posix_acl *acl; 67347e4937aSGao Xiang int prefix, rc; 67447e4937aSGao Xiang char *value = NULL; 67547e4937aSGao Xiang 6760cad6246SMiklos Szeredi if (rcu) 6770cad6246SMiklos Szeredi return ERR_PTR(-ECHILD); 6780cad6246SMiklos Szeredi 67947e4937aSGao Xiang switch (type) { 68047e4937aSGao Xiang case ACL_TYPE_ACCESS: 68147e4937aSGao Xiang prefix = EROFS_XATTR_INDEX_POSIX_ACL_ACCESS; 68247e4937aSGao Xiang break; 68347e4937aSGao Xiang case ACL_TYPE_DEFAULT: 68447e4937aSGao Xiang prefix = EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT; 68547e4937aSGao Xiang break; 68647e4937aSGao Xiang default: 68747e4937aSGao Xiang return ERR_PTR(-EINVAL); 68847e4937aSGao Xiang } 68947e4937aSGao Xiang 69047e4937aSGao Xiang rc = erofs_getxattr(inode, prefix, "", NULL, 0); 69147e4937aSGao Xiang if (rc > 0) { 69247e4937aSGao Xiang value = kmalloc(rc, GFP_KERNEL); 69347e4937aSGao Xiang if (!value) 69447e4937aSGao Xiang return ERR_PTR(-ENOMEM); 69547e4937aSGao Xiang rc = erofs_getxattr(inode, prefix, "", value, rc); 69647e4937aSGao Xiang } 69747e4937aSGao Xiang 69847e4937aSGao Xiang if (rc == -ENOATTR) 69947e4937aSGao Xiang acl = NULL; 70047e4937aSGao Xiang else if (rc < 0) 70147e4937aSGao Xiang acl = ERR_PTR(rc); 70247e4937aSGao Xiang else 70347e4937aSGao Xiang acl = posix_acl_from_xattr(&init_user_ns, value, rc); 70447e4937aSGao Xiang kfree(value); 70547e4937aSGao Xiang return acl; 70647e4937aSGao Xiang } 70747e4937aSGao Xiang #endif 708