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 1047e4937aSGao Xiang struct xattr_iter { 1147e4937aSGao Xiang struct super_block *sb; 12bb88e8daSGao Xiang struct erofs_buf buf; 1347e4937aSGao Xiang void *kaddr; 1447e4937aSGao Xiang 1547e4937aSGao Xiang erofs_blk_t blkaddr; 1647e4937aSGao Xiang unsigned int ofs; 1747e4937aSGao Xiang }; 1847e4937aSGao Xiang 1947e4937aSGao Xiang static int init_inode_xattrs(struct inode *inode) 2047e4937aSGao Xiang { 21a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 2247e4937aSGao Xiang struct xattr_iter it; 2347e4937aSGao Xiang unsigned int i; 2447e4937aSGao Xiang struct erofs_xattr_ibody_header *ih; 25*b780d3fcSGao Xiang struct super_block *sb = inode->i_sb; 2647e4937aSGao Xiang int ret = 0; 2747e4937aSGao Xiang 2847e4937aSGao Xiang /* the most case is that xattrs of this inode are initialized. */ 29ce063129SGao Xiang if (test_bit(EROFS_I_EA_INITED_BIT, &vi->flags)) { 30ce063129SGao Xiang /* 31ce063129SGao Xiang * paired with smp_mb() at the end of the function to ensure 32ce063129SGao Xiang * fields will only be observed after the bit is set. 33ce063129SGao Xiang */ 34ce063129SGao Xiang smp_mb(); 3547e4937aSGao Xiang return 0; 36ce063129SGao Xiang } 3747e4937aSGao Xiang 38a5876e24SGao Xiang if (wait_on_bit_lock(&vi->flags, EROFS_I_BL_XATTR_BIT, TASK_KILLABLE)) 3947e4937aSGao Xiang return -ERESTARTSYS; 4047e4937aSGao Xiang 4147e4937aSGao Xiang /* someone has initialized xattrs for us? */ 42a5876e24SGao Xiang if (test_bit(EROFS_I_EA_INITED_BIT, &vi->flags)) 4347e4937aSGao Xiang goto out_unlock; 4447e4937aSGao Xiang 4547e4937aSGao Xiang /* 4647e4937aSGao Xiang * bypass all xattr operations if ->xattr_isize is not greater than 4747e4937aSGao Xiang * sizeof(struct erofs_xattr_ibody_header), in detail: 4847e4937aSGao Xiang * 1) it is not enough to contain erofs_xattr_ibody_header then 4947e4937aSGao Xiang * ->xattr_isize should be 0 (it means no xattr); 5047e4937aSGao Xiang * 2) it is just to contain erofs_xattr_ibody_header, which is on-disk 5147e4937aSGao Xiang * undefined right now (maybe use later with some new sb feature). 5247e4937aSGao Xiang */ 5347e4937aSGao Xiang if (vi->xattr_isize == sizeof(struct erofs_xattr_ibody_header)) { 54*b780d3fcSGao Xiang erofs_err(sb, 554f761fa2SGao Xiang "xattr_isize %d of nid %llu is not supported yet", 5647e4937aSGao Xiang vi->xattr_isize, vi->nid); 5747e4937aSGao Xiang ret = -EOPNOTSUPP; 5847e4937aSGao Xiang goto out_unlock; 5947e4937aSGao Xiang } else if (vi->xattr_isize < sizeof(struct erofs_xattr_ibody_header)) { 608d8a09b0SGao Xiang if (vi->xattr_isize) { 61*b780d3fcSGao Xiang erofs_err(sb, "bogus xattr ibody @ nid %llu", vi->nid); 6247e4937aSGao Xiang DBG_BUGON(1); 6347e4937aSGao Xiang ret = -EFSCORRUPTED; 6447e4937aSGao Xiang goto out_unlock; /* xattr ondisk layout error */ 6547e4937aSGao Xiang } 6647e4937aSGao Xiang ret = -ENOATTR; 6747e4937aSGao Xiang goto out_unlock; 6847e4937aSGao Xiang } 6947e4937aSGao Xiang 70bb88e8daSGao Xiang it.buf = __EROFS_BUF_INITIALIZER; 71*b780d3fcSGao Xiang it.blkaddr = erofs_blknr(erofs_iloc(inode) + vi->inode_isize); 72*b780d3fcSGao Xiang it.ofs = erofs_blkoff(erofs_iloc(inode) + vi->inode_isize); 7347e4937aSGao Xiang 74bb88e8daSGao Xiang /* read in shared xattr array (non-atomic, see kmalloc below) */ 75bb88e8daSGao Xiang it.kaddr = erofs_read_metabuf(&it.buf, sb, it.blkaddr, EROFS_KMAP); 76bb88e8daSGao Xiang if (IS_ERR(it.kaddr)) { 77bb88e8daSGao Xiang ret = PTR_ERR(it.kaddr); 7847e4937aSGao Xiang goto out_unlock; 7947e4937aSGao Xiang } 8047e4937aSGao Xiang 8147e4937aSGao Xiang ih = (struct erofs_xattr_ibody_header *)(it.kaddr + it.ofs); 8247e4937aSGao Xiang vi->xattr_shared_count = ih->h_shared_count; 8347e4937aSGao Xiang vi->xattr_shared_xattrs = kmalloc_array(vi->xattr_shared_count, 8447e4937aSGao Xiang sizeof(uint), GFP_KERNEL); 8547e4937aSGao Xiang if (!vi->xattr_shared_xattrs) { 86bb88e8daSGao Xiang erofs_put_metabuf(&it.buf); 8747e4937aSGao Xiang ret = -ENOMEM; 8847e4937aSGao Xiang goto out_unlock; 8947e4937aSGao Xiang } 9047e4937aSGao Xiang 9147e4937aSGao Xiang /* let's skip ibody header */ 9247e4937aSGao Xiang it.ofs += sizeof(struct erofs_xattr_ibody_header); 9347e4937aSGao Xiang 9447e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 958d8a09b0SGao Xiang if (it.ofs >= EROFS_BLKSIZ) { 9647e4937aSGao Xiang /* cannot be unaligned */ 9747e4937aSGao Xiang DBG_BUGON(it.ofs != EROFS_BLKSIZ); 9847e4937aSGao Xiang 99bb88e8daSGao Xiang it.kaddr = erofs_read_metabuf(&it.buf, sb, ++it.blkaddr, 100bb88e8daSGao Xiang EROFS_KMAP); 101bb88e8daSGao Xiang if (IS_ERR(it.kaddr)) { 10247e4937aSGao Xiang kfree(vi->xattr_shared_xattrs); 10347e4937aSGao Xiang vi->xattr_shared_xattrs = NULL; 104bb88e8daSGao Xiang ret = PTR_ERR(it.kaddr); 10547e4937aSGao Xiang goto out_unlock; 10647e4937aSGao Xiang } 10747e4937aSGao Xiang it.ofs = 0; 10847e4937aSGao Xiang } 10947e4937aSGao Xiang vi->xattr_shared_xattrs[i] = 11047e4937aSGao Xiang le32_to_cpu(*(__le32 *)(it.kaddr + it.ofs)); 11147e4937aSGao Xiang it.ofs += sizeof(__le32); 11247e4937aSGao Xiang } 113bb88e8daSGao Xiang erofs_put_metabuf(&it.buf); 11447e4937aSGao Xiang 115ce063129SGao Xiang /* paired with smp_mb() at the beginning of the function. */ 116ce063129SGao Xiang smp_mb(); 117a5876e24SGao Xiang set_bit(EROFS_I_EA_INITED_BIT, &vi->flags); 11847e4937aSGao Xiang 11947e4937aSGao Xiang out_unlock: 120a5876e24SGao Xiang clear_and_wake_up_bit(EROFS_I_BL_XATTR_BIT, &vi->flags); 12147e4937aSGao Xiang return ret; 12247e4937aSGao Xiang } 12347e4937aSGao Xiang 12447e4937aSGao Xiang /* 12547e4937aSGao Xiang * the general idea for these return values is 12647e4937aSGao Xiang * if 0 is returned, go on processing the current xattr; 12747e4937aSGao Xiang * 1 (> 0) is returned, skip this round to process the next xattr; 12847e4937aSGao Xiang * -err (< 0) is returned, an error (maybe ENOXATTR) occurred 12947e4937aSGao Xiang * and need to be handled 13047e4937aSGao Xiang */ 13147e4937aSGao Xiang struct xattr_iter_handlers { 13247e4937aSGao Xiang int (*entry)(struct xattr_iter *_it, struct erofs_xattr_entry *entry); 13347e4937aSGao Xiang int (*name)(struct xattr_iter *_it, unsigned int processed, char *buf, 13447e4937aSGao Xiang unsigned int len); 13547e4937aSGao Xiang int (*alloc_buffer)(struct xattr_iter *_it, unsigned int value_sz); 13647e4937aSGao Xiang void (*value)(struct xattr_iter *_it, unsigned int processed, char *buf, 13747e4937aSGao Xiang unsigned int len); 13847e4937aSGao Xiang }; 13947e4937aSGao Xiang 14047e4937aSGao Xiang static inline int xattr_iter_fixup(struct xattr_iter *it) 14147e4937aSGao Xiang { 14247e4937aSGao Xiang if (it->ofs < EROFS_BLKSIZ) 14347e4937aSGao Xiang return 0; 14447e4937aSGao Xiang 14547e4937aSGao Xiang it->blkaddr += erofs_blknr(it->ofs); 146bb88e8daSGao Xiang it->kaddr = erofs_read_metabuf(&it->buf, it->sb, it->blkaddr, 147927e5010SGao Xiang EROFS_KMAP); 148bb88e8daSGao Xiang if (IS_ERR(it->kaddr)) 149bb88e8daSGao Xiang return PTR_ERR(it->kaddr); 15047e4937aSGao Xiang it->ofs = erofs_blkoff(it->ofs); 15147e4937aSGao Xiang return 0; 15247e4937aSGao Xiang } 15347e4937aSGao Xiang 15447e4937aSGao Xiang static int inline_xattr_iter_begin(struct xattr_iter *it, 15547e4937aSGao Xiang struct inode *inode) 15647e4937aSGao Xiang { 157a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 15847e4937aSGao Xiang unsigned int xattr_header_sz, inline_xattr_ofs; 15947e4937aSGao Xiang 16047e4937aSGao Xiang xattr_header_sz = inlinexattr_header_size(inode); 1618d8a09b0SGao Xiang if (xattr_header_sz >= vi->xattr_isize) { 16247e4937aSGao Xiang DBG_BUGON(xattr_header_sz > vi->xattr_isize); 16347e4937aSGao Xiang return -ENOATTR; 16447e4937aSGao Xiang } 16547e4937aSGao Xiang 16647e4937aSGao Xiang inline_xattr_ofs = vi->inode_isize + xattr_header_sz; 16747e4937aSGao Xiang 168*b780d3fcSGao Xiang it->blkaddr = erofs_blknr(erofs_iloc(inode) + inline_xattr_ofs); 169*b780d3fcSGao Xiang it->ofs = erofs_blkoff(erofs_iloc(inode) + inline_xattr_ofs); 170bb88e8daSGao Xiang it->kaddr = erofs_read_metabuf(&it->buf, inode->i_sb, it->blkaddr, 171927e5010SGao Xiang EROFS_KMAP); 172bb88e8daSGao Xiang if (IS_ERR(it->kaddr)) 173bb88e8daSGao Xiang return PTR_ERR(it->kaddr); 17447e4937aSGao Xiang return vi->xattr_isize - xattr_header_sz; 17547e4937aSGao Xiang } 17647e4937aSGao Xiang 17747e4937aSGao Xiang /* 17847e4937aSGao Xiang * Regardless of success or failure, `xattr_foreach' will end up with 17947e4937aSGao Xiang * `ofs' pointing to the next xattr item rather than an arbitrary position. 18047e4937aSGao Xiang */ 18147e4937aSGao Xiang static int xattr_foreach(struct xattr_iter *it, 18247e4937aSGao Xiang const struct xattr_iter_handlers *op, 18347e4937aSGao Xiang unsigned int *tlimit) 18447e4937aSGao Xiang { 18547e4937aSGao Xiang struct erofs_xattr_entry entry; 18647e4937aSGao Xiang unsigned int value_sz, processed, slice; 18747e4937aSGao Xiang int err; 18847e4937aSGao Xiang 18947e4937aSGao Xiang /* 0. fixup blkaddr, ofs, ipage */ 19047e4937aSGao Xiang err = xattr_iter_fixup(it); 19147e4937aSGao Xiang if (err) 19247e4937aSGao Xiang return err; 19347e4937aSGao Xiang 19447e4937aSGao Xiang /* 19547e4937aSGao Xiang * 1. read xattr entry to the memory, 19647e4937aSGao Xiang * since we do EROFS_XATTR_ALIGN 19747e4937aSGao Xiang * therefore entry should be in the page 19847e4937aSGao Xiang */ 19947e4937aSGao Xiang entry = *(struct erofs_xattr_entry *)(it->kaddr + it->ofs); 20047e4937aSGao Xiang if (tlimit) { 201b6796abdSGao Xiang unsigned int entry_sz = erofs_xattr_entry_size(&entry); 20247e4937aSGao Xiang 20347e4937aSGao Xiang /* xattr on-disk corruption: xattr entry beyond xattr_isize */ 2048d8a09b0SGao Xiang if (*tlimit < entry_sz) { 20547e4937aSGao Xiang DBG_BUGON(1); 20647e4937aSGao Xiang return -EFSCORRUPTED; 20747e4937aSGao Xiang } 20847e4937aSGao Xiang *tlimit -= entry_sz; 20947e4937aSGao Xiang } 21047e4937aSGao Xiang 21147e4937aSGao Xiang it->ofs += sizeof(struct erofs_xattr_entry); 21247e4937aSGao Xiang value_sz = le16_to_cpu(entry.e_value_size); 21347e4937aSGao Xiang 21447e4937aSGao Xiang /* handle entry */ 21547e4937aSGao Xiang err = op->entry(it, &entry); 21647e4937aSGao Xiang if (err) { 21747e4937aSGao Xiang it->ofs += entry.e_name_len + value_sz; 21847e4937aSGao Xiang goto out; 21947e4937aSGao Xiang } 22047e4937aSGao Xiang 22147e4937aSGao Xiang /* 2. handle xattr name (ofs will finally be at the end of name) */ 22247e4937aSGao Xiang processed = 0; 22347e4937aSGao Xiang 22447e4937aSGao Xiang while (processed < entry.e_name_len) { 22547e4937aSGao Xiang if (it->ofs >= EROFS_BLKSIZ) { 22647e4937aSGao Xiang DBG_BUGON(it->ofs > EROFS_BLKSIZ); 22747e4937aSGao Xiang 22847e4937aSGao Xiang err = xattr_iter_fixup(it); 22947e4937aSGao Xiang if (err) 23047e4937aSGao Xiang goto out; 23147e4937aSGao Xiang it->ofs = 0; 23247e4937aSGao Xiang } 23347e4937aSGao Xiang 234bb88e8daSGao Xiang slice = min_t(unsigned int, EROFS_BLKSIZ - it->ofs, 23547e4937aSGao Xiang entry.e_name_len - processed); 23647e4937aSGao Xiang 23747e4937aSGao Xiang /* handle name */ 23847e4937aSGao Xiang err = op->name(it, processed, it->kaddr + it->ofs, slice); 23947e4937aSGao Xiang if (err) { 24047e4937aSGao Xiang it->ofs += entry.e_name_len - processed + value_sz; 24147e4937aSGao Xiang goto out; 24247e4937aSGao Xiang } 24347e4937aSGao Xiang 24447e4937aSGao Xiang it->ofs += slice; 24547e4937aSGao Xiang processed += slice; 24647e4937aSGao Xiang } 24747e4937aSGao Xiang 24847e4937aSGao Xiang /* 3. handle xattr value */ 24947e4937aSGao Xiang processed = 0; 25047e4937aSGao Xiang 25147e4937aSGao Xiang if (op->alloc_buffer) { 25247e4937aSGao Xiang err = op->alloc_buffer(it, value_sz); 25347e4937aSGao Xiang if (err) { 25447e4937aSGao Xiang it->ofs += value_sz; 25547e4937aSGao Xiang goto out; 25647e4937aSGao Xiang } 25747e4937aSGao Xiang } 25847e4937aSGao Xiang 25947e4937aSGao Xiang while (processed < value_sz) { 26047e4937aSGao Xiang if (it->ofs >= EROFS_BLKSIZ) { 26147e4937aSGao Xiang DBG_BUGON(it->ofs > EROFS_BLKSIZ); 26247e4937aSGao Xiang 26347e4937aSGao Xiang err = xattr_iter_fixup(it); 26447e4937aSGao Xiang if (err) 26547e4937aSGao Xiang goto out; 26647e4937aSGao Xiang it->ofs = 0; 26747e4937aSGao Xiang } 26847e4937aSGao Xiang 269bb88e8daSGao Xiang slice = min_t(unsigned int, EROFS_BLKSIZ - it->ofs, 27047e4937aSGao Xiang value_sz - processed); 27147e4937aSGao Xiang op->value(it, processed, it->kaddr + it->ofs, slice); 27247e4937aSGao Xiang it->ofs += slice; 27347e4937aSGao Xiang processed += slice; 27447e4937aSGao Xiang } 27547e4937aSGao Xiang 27647e4937aSGao Xiang out: 27747e4937aSGao Xiang /* xattrs should be 4-byte aligned (on-disk constraint) */ 27847e4937aSGao Xiang it->ofs = EROFS_XATTR_ALIGN(it->ofs); 27947e4937aSGao Xiang return err < 0 ? err : 0; 28047e4937aSGao Xiang } 28147e4937aSGao Xiang 28247e4937aSGao Xiang struct getxattr_iter { 28347e4937aSGao Xiang struct xattr_iter it; 28447e4937aSGao Xiang 28547e4937aSGao Xiang char *buffer; 28647e4937aSGao Xiang int buffer_size, index; 28747e4937aSGao Xiang struct qstr name; 28847e4937aSGao Xiang }; 28947e4937aSGao Xiang 29047e4937aSGao Xiang static int xattr_entrymatch(struct xattr_iter *_it, 29147e4937aSGao Xiang struct erofs_xattr_entry *entry) 29247e4937aSGao Xiang { 29347e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 29447e4937aSGao Xiang 29547e4937aSGao Xiang return (it->index != entry->e_name_index || 29647e4937aSGao Xiang it->name.len != entry->e_name_len) ? -ENOATTR : 0; 29747e4937aSGao Xiang } 29847e4937aSGao Xiang 29947e4937aSGao Xiang static int xattr_namematch(struct xattr_iter *_it, 30047e4937aSGao Xiang unsigned int processed, char *buf, unsigned int len) 30147e4937aSGao Xiang { 30247e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 30347e4937aSGao Xiang 30447e4937aSGao Xiang return memcmp(buf, it->name.name + processed, len) ? -ENOATTR : 0; 30547e4937aSGao Xiang } 30647e4937aSGao Xiang 30747e4937aSGao Xiang static int xattr_checkbuffer(struct xattr_iter *_it, 30847e4937aSGao Xiang unsigned int value_sz) 30947e4937aSGao Xiang { 31047e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 31147e4937aSGao Xiang int err = it->buffer_size < value_sz ? -ERANGE : 0; 31247e4937aSGao Xiang 31347e4937aSGao Xiang it->buffer_size = value_sz; 31447e4937aSGao Xiang return !it->buffer ? 1 : err; 31547e4937aSGao Xiang } 31647e4937aSGao Xiang 31747e4937aSGao Xiang static void xattr_copyvalue(struct xattr_iter *_it, 31847e4937aSGao Xiang unsigned int processed, 31947e4937aSGao Xiang char *buf, unsigned int len) 32047e4937aSGao Xiang { 32147e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 32247e4937aSGao Xiang 32347e4937aSGao Xiang memcpy(it->buffer + processed, buf, len); 32447e4937aSGao Xiang } 32547e4937aSGao Xiang 32647e4937aSGao Xiang static const struct xattr_iter_handlers find_xattr_handlers = { 32747e4937aSGao Xiang .entry = xattr_entrymatch, 32847e4937aSGao Xiang .name = xattr_namematch, 32947e4937aSGao Xiang .alloc_buffer = xattr_checkbuffer, 33047e4937aSGao Xiang .value = xattr_copyvalue 33147e4937aSGao Xiang }; 33247e4937aSGao Xiang 33347e4937aSGao Xiang static int inline_getxattr(struct inode *inode, struct getxattr_iter *it) 33447e4937aSGao Xiang { 33547e4937aSGao Xiang int ret; 33647e4937aSGao Xiang unsigned int remaining; 33747e4937aSGao Xiang 33847e4937aSGao Xiang ret = inline_xattr_iter_begin(&it->it, inode); 33947e4937aSGao Xiang if (ret < 0) 34047e4937aSGao Xiang return ret; 34147e4937aSGao Xiang 34247e4937aSGao Xiang remaining = ret; 34347e4937aSGao Xiang while (remaining) { 34447e4937aSGao Xiang ret = xattr_foreach(&it->it, &find_xattr_handlers, &remaining); 34547e4937aSGao Xiang if (ret != -ENOATTR) 34647e4937aSGao Xiang break; 34747e4937aSGao Xiang } 34847e4937aSGao Xiang return ret ? ret : it->buffer_size; 34947e4937aSGao Xiang } 35047e4937aSGao Xiang 35147e4937aSGao Xiang static int shared_getxattr(struct inode *inode, struct getxattr_iter *it) 35247e4937aSGao Xiang { 353a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 35447e4937aSGao Xiang struct super_block *const sb = inode->i_sb; 35547e4937aSGao Xiang struct erofs_sb_info *const sbi = EROFS_SB(sb); 35647e4937aSGao Xiang unsigned int i; 35747e4937aSGao Xiang int ret = -ENOATTR; 35847e4937aSGao Xiang 35947e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 36047e4937aSGao Xiang erofs_blk_t blkaddr = 36147e4937aSGao Xiang xattrblock_addr(sbi, vi->xattr_shared_xattrs[i]); 36247e4937aSGao Xiang 36347e4937aSGao Xiang it->it.ofs = xattrblock_offset(sbi, vi->xattr_shared_xattrs[i]); 364bb88e8daSGao Xiang it->it.kaddr = erofs_read_metabuf(&it->it.buf, sb, blkaddr, 365927e5010SGao Xiang EROFS_KMAP); 366bb88e8daSGao Xiang if (IS_ERR(it->it.kaddr)) 367bb88e8daSGao Xiang return PTR_ERR(it->it.kaddr); 36847e4937aSGao Xiang it->it.blkaddr = blkaddr; 36947e4937aSGao Xiang 37047e4937aSGao Xiang ret = xattr_foreach(&it->it, &find_xattr_handlers, NULL); 37147e4937aSGao Xiang if (ret != -ENOATTR) 37247e4937aSGao Xiang break; 37347e4937aSGao Xiang } 37447e4937aSGao Xiang return ret ? ret : it->buffer_size; 37547e4937aSGao Xiang } 37647e4937aSGao Xiang 37747e4937aSGao Xiang static bool erofs_xattr_user_list(struct dentry *dentry) 37847e4937aSGao Xiang { 379e6242465SGao Xiang return test_opt(&EROFS_SB(dentry->d_sb)->opt, XATTR_USER); 38047e4937aSGao Xiang } 38147e4937aSGao Xiang 38247e4937aSGao Xiang static bool erofs_xattr_trusted_list(struct dentry *dentry) 38347e4937aSGao Xiang { 38447e4937aSGao Xiang return capable(CAP_SYS_ADMIN); 38547e4937aSGao Xiang } 38647e4937aSGao Xiang 38747e4937aSGao Xiang int erofs_getxattr(struct inode *inode, int index, 38847e4937aSGao Xiang const char *name, 38947e4937aSGao Xiang void *buffer, size_t buffer_size) 39047e4937aSGao Xiang { 39147e4937aSGao Xiang int ret; 39247e4937aSGao Xiang struct getxattr_iter it; 39347e4937aSGao Xiang 3948d8a09b0SGao Xiang if (!name) 39547e4937aSGao Xiang return -EINVAL; 39647e4937aSGao Xiang 39747e4937aSGao Xiang ret = init_inode_xattrs(inode); 39847e4937aSGao Xiang if (ret) 39947e4937aSGao Xiang return ret; 40047e4937aSGao Xiang 40147e4937aSGao Xiang it.index = index; 40247e4937aSGao Xiang it.name.len = strlen(name); 40347e4937aSGao Xiang if (it.name.len > EROFS_NAME_LEN) 40447e4937aSGao Xiang return -ERANGE; 405bb88e8daSGao Xiang 406bb88e8daSGao Xiang it.it.buf = __EROFS_BUF_INITIALIZER; 40747e4937aSGao Xiang it.name.name = name; 40847e4937aSGao Xiang 40947e4937aSGao Xiang it.buffer = buffer; 41047e4937aSGao Xiang it.buffer_size = buffer_size; 41147e4937aSGao Xiang 41247e4937aSGao Xiang it.it.sb = inode->i_sb; 41347e4937aSGao Xiang ret = inline_getxattr(inode, &it); 41447e4937aSGao Xiang if (ret == -ENOATTR) 41547e4937aSGao Xiang ret = shared_getxattr(inode, &it); 416bb88e8daSGao Xiang erofs_put_metabuf(&it.it.buf); 41747e4937aSGao Xiang return ret; 41847e4937aSGao Xiang } 41947e4937aSGao Xiang 42047e4937aSGao Xiang static int erofs_xattr_generic_get(const struct xattr_handler *handler, 42147e4937aSGao Xiang struct dentry *unused, struct inode *inode, 42247e4937aSGao Xiang const char *name, void *buffer, size_t size) 42347e4937aSGao Xiang { 42447e4937aSGao Xiang struct erofs_sb_info *const sbi = EROFS_I_SB(inode); 42547e4937aSGao Xiang 42647e4937aSGao Xiang switch (handler->flags) { 42747e4937aSGao Xiang case EROFS_XATTR_INDEX_USER: 428e6242465SGao Xiang if (!test_opt(&sbi->opt, XATTR_USER)) 42947e4937aSGao Xiang return -EOPNOTSUPP; 43047e4937aSGao Xiang break; 43147e4937aSGao Xiang case EROFS_XATTR_INDEX_TRUSTED: 43247e4937aSGao Xiang break; 43347e4937aSGao Xiang case EROFS_XATTR_INDEX_SECURITY: 43447e4937aSGao Xiang break; 43547e4937aSGao Xiang default: 43647e4937aSGao Xiang return -EINVAL; 43747e4937aSGao Xiang } 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); 56647e4937aSGao Xiang struct super_block *const sb = inode->i_sb; 56747e4937aSGao Xiang struct erofs_sb_info *const sbi = EROFS_SB(sb); 56847e4937aSGao Xiang unsigned int i; 56947e4937aSGao Xiang int ret = 0; 57047e4937aSGao Xiang 57147e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 57247e4937aSGao Xiang erofs_blk_t blkaddr = 57347e4937aSGao Xiang xattrblock_addr(sbi, vi->xattr_shared_xattrs[i]); 57447e4937aSGao Xiang 57547e4937aSGao Xiang it->it.ofs = xattrblock_offset(sbi, vi->xattr_shared_xattrs[i]); 576bb88e8daSGao Xiang it->it.kaddr = erofs_read_metabuf(&it->it.buf, sb, blkaddr, 577927e5010SGao Xiang EROFS_KMAP); 578bb88e8daSGao Xiang if (IS_ERR(it->it.kaddr)) 579bb88e8daSGao Xiang return PTR_ERR(it->it.kaddr); 58047e4937aSGao Xiang it->it.blkaddr = blkaddr; 58147e4937aSGao Xiang 58247e4937aSGao Xiang ret = xattr_foreach(&it->it, &list_xattr_handlers, NULL); 58347e4937aSGao Xiang if (ret) 58447e4937aSGao Xiang break; 58547e4937aSGao Xiang } 58647e4937aSGao Xiang return ret ? ret : it->buffer_ofs; 58747e4937aSGao Xiang } 58847e4937aSGao Xiang 58947e4937aSGao Xiang ssize_t erofs_listxattr(struct dentry *dentry, 59047e4937aSGao Xiang char *buffer, size_t buffer_size) 59147e4937aSGao Xiang { 59247e4937aSGao Xiang int ret; 59347e4937aSGao Xiang struct listxattr_iter it; 59447e4937aSGao Xiang 59547e4937aSGao Xiang ret = init_inode_xattrs(d_inode(dentry)); 596926d1650SGao Xiang if (ret == -ENOATTR) 597926d1650SGao Xiang return 0; 59847e4937aSGao Xiang if (ret) 59947e4937aSGao Xiang return ret; 60047e4937aSGao Xiang 601bb88e8daSGao Xiang it.it.buf = __EROFS_BUF_INITIALIZER; 60247e4937aSGao Xiang it.dentry = dentry; 60347e4937aSGao Xiang it.buffer = buffer; 60447e4937aSGao Xiang it.buffer_size = buffer_size; 60547e4937aSGao Xiang it.buffer_ofs = 0; 60647e4937aSGao Xiang 60747e4937aSGao Xiang it.it.sb = dentry->d_sb; 60847e4937aSGao Xiang 60947e4937aSGao Xiang ret = inline_listxattr(&it); 610bb88e8daSGao Xiang if (ret >= 0 || ret == -ENOATTR) 611bb88e8daSGao Xiang ret = shared_listxattr(&it); 612bb88e8daSGao Xiang erofs_put_metabuf(&it.it.buf); 61347e4937aSGao Xiang return ret; 61447e4937aSGao Xiang } 61547e4937aSGao Xiang 61647e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_POSIX_ACL 6170cad6246SMiklos Szeredi struct posix_acl *erofs_get_acl(struct inode *inode, int type, bool rcu) 61847e4937aSGao Xiang { 61947e4937aSGao Xiang struct posix_acl *acl; 62047e4937aSGao Xiang int prefix, rc; 62147e4937aSGao Xiang char *value = NULL; 62247e4937aSGao Xiang 6230cad6246SMiklos Szeredi if (rcu) 6240cad6246SMiklos Szeredi return ERR_PTR(-ECHILD); 6250cad6246SMiklos Szeredi 62647e4937aSGao Xiang switch (type) { 62747e4937aSGao Xiang case ACL_TYPE_ACCESS: 62847e4937aSGao Xiang prefix = EROFS_XATTR_INDEX_POSIX_ACL_ACCESS; 62947e4937aSGao Xiang break; 63047e4937aSGao Xiang case ACL_TYPE_DEFAULT: 63147e4937aSGao Xiang prefix = EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT; 63247e4937aSGao Xiang break; 63347e4937aSGao Xiang default: 63447e4937aSGao Xiang return ERR_PTR(-EINVAL); 63547e4937aSGao Xiang } 63647e4937aSGao Xiang 63747e4937aSGao Xiang rc = erofs_getxattr(inode, prefix, "", NULL, 0); 63847e4937aSGao Xiang if (rc > 0) { 63947e4937aSGao Xiang value = kmalloc(rc, GFP_KERNEL); 64047e4937aSGao Xiang if (!value) 64147e4937aSGao Xiang return ERR_PTR(-ENOMEM); 64247e4937aSGao Xiang rc = erofs_getxattr(inode, prefix, "", value, rc); 64347e4937aSGao Xiang } 64447e4937aSGao Xiang 64547e4937aSGao Xiang if (rc == -ENOATTR) 64647e4937aSGao Xiang acl = NULL; 64747e4937aSGao Xiang else if (rc < 0) 64847e4937aSGao Xiang acl = ERR_PTR(rc); 64947e4937aSGao Xiang else 65047e4937aSGao Xiang acl = posix_acl_from_xattr(&init_user_ns, value, rc); 65147e4937aSGao Xiang kfree(value); 65247e4937aSGao Xiang return acl; 65347e4937aSGao Xiang } 65447e4937aSGao Xiang #endif 655