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; 13*eba67eb6SJingbo Xu erofs_off_t pos; 1447e4937aSGao Xiang void *kaddr; 1547e4937aSGao Xiang }; 1647e4937aSGao Xiang 176020ffe7SJingbo Xu static int erofs_init_inode_xattrs(struct inode *inode) 1847e4937aSGao Xiang { 19a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 2047e4937aSGao Xiang struct xattr_iter it; 2147e4937aSGao Xiang unsigned int i; 2247e4937aSGao Xiang struct erofs_xattr_ibody_header *ih; 23b780d3fcSGao Xiang struct super_block *sb = inode->i_sb; 2447e4937aSGao Xiang int ret = 0; 2547e4937aSGao Xiang 2647e4937aSGao Xiang /* the most case is that xattrs of this inode are initialized. */ 27ce063129SGao Xiang if (test_bit(EROFS_I_EA_INITED_BIT, &vi->flags)) { 28ce063129SGao Xiang /* 29ce063129SGao Xiang * paired with smp_mb() at the end of the function to ensure 30ce063129SGao Xiang * fields will only be observed after the bit is set. 31ce063129SGao Xiang */ 32ce063129SGao Xiang smp_mb(); 3347e4937aSGao Xiang return 0; 34ce063129SGao Xiang } 3547e4937aSGao Xiang 36a5876e24SGao Xiang if (wait_on_bit_lock(&vi->flags, EROFS_I_BL_XATTR_BIT, TASK_KILLABLE)) 3747e4937aSGao Xiang return -ERESTARTSYS; 3847e4937aSGao Xiang 3947e4937aSGao Xiang /* someone has initialized xattrs for us? */ 40a5876e24SGao Xiang if (test_bit(EROFS_I_EA_INITED_BIT, &vi->flags)) 4147e4937aSGao Xiang goto out_unlock; 4247e4937aSGao Xiang 4347e4937aSGao Xiang /* 4447e4937aSGao Xiang * bypass all xattr operations if ->xattr_isize is not greater than 4547e4937aSGao Xiang * sizeof(struct erofs_xattr_ibody_header), in detail: 4647e4937aSGao Xiang * 1) it is not enough to contain erofs_xattr_ibody_header then 4747e4937aSGao Xiang * ->xattr_isize should be 0 (it means no xattr); 4847e4937aSGao Xiang * 2) it is just to contain erofs_xattr_ibody_header, which is on-disk 4947e4937aSGao Xiang * undefined right now (maybe use later with some new sb feature). 5047e4937aSGao Xiang */ 5147e4937aSGao Xiang if (vi->xattr_isize == sizeof(struct erofs_xattr_ibody_header)) { 52b780d3fcSGao Xiang erofs_err(sb, 534f761fa2SGao Xiang "xattr_isize %d of nid %llu is not supported yet", 5447e4937aSGao Xiang vi->xattr_isize, vi->nid); 5547e4937aSGao Xiang ret = -EOPNOTSUPP; 5647e4937aSGao Xiang goto out_unlock; 5747e4937aSGao Xiang } else if (vi->xattr_isize < sizeof(struct erofs_xattr_ibody_header)) { 588d8a09b0SGao Xiang if (vi->xattr_isize) { 59b780d3fcSGao Xiang erofs_err(sb, "bogus xattr ibody @ nid %llu", vi->nid); 6047e4937aSGao Xiang DBG_BUGON(1); 6147e4937aSGao Xiang ret = -EFSCORRUPTED; 6247e4937aSGao Xiang goto out_unlock; /* xattr ondisk layout error */ 6347e4937aSGao Xiang } 6447e4937aSGao Xiang ret = -ENOATTR; 6547e4937aSGao Xiang goto out_unlock; 6647e4937aSGao Xiang } 6747e4937aSGao Xiang 68bb88e8daSGao Xiang it.buf = __EROFS_BUF_INITIALIZER; 699c39ec0cSJingbo Xu erofs_init_metabuf(&it.buf, sb); 70*eba67eb6SJingbo Xu it.pos = erofs_iloc(inode) + vi->inode_isize; 7147e4937aSGao Xiang 72bb88e8daSGao Xiang /* read in shared xattr array (non-atomic, see kmalloc below) */ 73*eba67eb6SJingbo Xu it.kaddr = erofs_bread(&it.buf, erofs_blknr(sb, it.pos), EROFS_KMAP); 74bb88e8daSGao Xiang if (IS_ERR(it.kaddr)) { 75bb88e8daSGao Xiang ret = PTR_ERR(it.kaddr); 7647e4937aSGao Xiang goto out_unlock; 7747e4937aSGao Xiang } 7847e4937aSGao Xiang 79*eba67eb6SJingbo Xu ih = it.kaddr + erofs_blkoff(sb, it.pos); 8047e4937aSGao Xiang vi->xattr_shared_count = ih->h_shared_count; 8147e4937aSGao Xiang vi->xattr_shared_xattrs = kmalloc_array(vi->xattr_shared_count, 8247e4937aSGao Xiang sizeof(uint), GFP_KERNEL); 8347e4937aSGao Xiang if (!vi->xattr_shared_xattrs) { 84bb88e8daSGao Xiang erofs_put_metabuf(&it.buf); 8547e4937aSGao Xiang ret = -ENOMEM; 8647e4937aSGao Xiang goto out_unlock; 8747e4937aSGao Xiang } 8847e4937aSGao Xiang 8947e4937aSGao Xiang /* let's skip ibody header */ 90*eba67eb6SJingbo Xu it.pos += sizeof(struct erofs_xattr_ibody_header); 9147e4937aSGao Xiang 9247e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 93*eba67eb6SJingbo Xu it.kaddr = erofs_bread(&it.buf, erofs_blknr(sb, it.pos), 94*eba67eb6SJingbo Xu EROFS_KMAP); 95bb88e8daSGao Xiang if (IS_ERR(it.kaddr)) { 9647e4937aSGao Xiang kfree(vi->xattr_shared_xattrs); 9747e4937aSGao Xiang vi->xattr_shared_xattrs = NULL; 98bb88e8daSGao Xiang ret = PTR_ERR(it.kaddr); 9947e4937aSGao Xiang goto out_unlock; 10047e4937aSGao Xiang } 101*eba67eb6SJingbo Xu vi->xattr_shared_xattrs[i] = le32_to_cpu(*(__le32 *) 102*eba67eb6SJingbo Xu (it.kaddr + erofs_blkoff(sb, it.pos))); 103*eba67eb6SJingbo Xu it.pos += sizeof(__le32); 10447e4937aSGao Xiang } 105bb88e8daSGao Xiang erofs_put_metabuf(&it.buf); 10647e4937aSGao Xiang 107ce063129SGao Xiang /* paired with smp_mb() at the beginning of the function. */ 108ce063129SGao Xiang smp_mb(); 109a5876e24SGao Xiang set_bit(EROFS_I_EA_INITED_BIT, &vi->flags); 11047e4937aSGao Xiang 11147e4937aSGao Xiang out_unlock: 112a5876e24SGao Xiang clear_and_wake_up_bit(EROFS_I_BL_XATTR_BIT, &vi->flags); 11347e4937aSGao Xiang return ret; 11447e4937aSGao Xiang } 11547e4937aSGao Xiang 11647e4937aSGao Xiang /* 11747e4937aSGao Xiang * the general idea for these return values is 11847e4937aSGao Xiang * if 0 is returned, go on processing the current xattr; 11947e4937aSGao Xiang * 1 (> 0) is returned, skip this round to process the next xattr; 12047e4937aSGao Xiang * -err (< 0) is returned, an error (maybe ENOXATTR) occurred 12147e4937aSGao Xiang * and need to be handled 12247e4937aSGao Xiang */ 12347e4937aSGao Xiang struct xattr_iter_handlers { 12447e4937aSGao Xiang int (*entry)(struct xattr_iter *_it, struct erofs_xattr_entry *entry); 12547e4937aSGao Xiang int (*name)(struct xattr_iter *_it, unsigned int processed, char *buf, 12647e4937aSGao Xiang unsigned int len); 12747e4937aSGao Xiang int (*alloc_buffer)(struct xattr_iter *_it, unsigned int value_sz); 12847e4937aSGao Xiang void (*value)(struct xattr_iter *_it, unsigned int processed, char *buf, 12947e4937aSGao Xiang unsigned int len); 13047e4937aSGao Xiang }; 13147e4937aSGao Xiang 13247e4937aSGao Xiang static int inline_xattr_iter_begin(struct xattr_iter *it, 13347e4937aSGao Xiang struct inode *inode) 13447e4937aSGao Xiang { 135a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 136*eba67eb6SJingbo Xu unsigned int xattr_header_sz; 13747e4937aSGao Xiang 138399f36d8SJingbo Xu xattr_header_sz = sizeof(struct erofs_xattr_ibody_header) + 139399f36d8SJingbo Xu sizeof(u32) * vi->xattr_shared_count; 1408d8a09b0SGao Xiang if (xattr_header_sz >= vi->xattr_isize) { 14147e4937aSGao Xiang DBG_BUGON(xattr_header_sz > vi->xattr_isize); 14247e4937aSGao Xiang return -ENOATTR; 14347e4937aSGao Xiang } 14447e4937aSGao Xiang 145*eba67eb6SJingbo Xu it->pos = erofs_iloc(inode) + vi->inode_isize + xattr_header_sz; 146*eba67eb6SJingbo Xu it->kaddr = erofs_bread(&it->buf, erofs_blknr(it->sb, it->pos), 147*eba67eb6SJingbo Xu EROFS_KMAP); 148bb88e8daSGao Xiang if (IS_ERR(it->kaddr)) 149bb88e8daSGao Xiang return PTR_ERR(it->kaddr); 15047e4937aSGao Xiang return vi->xattr_isize - xattr_header_sz; 15147e4937aSGao Xiang } 15247e4937aSGao Xiang 15347e4937aSGao Xiang /* 15447e4937aSGao Xiang * Regardless of success or failure, `xattr_foreach' will end up with 155*eba67eb6SJingbo Xu * `pos' pointing to the next xattr item rather than an arbitrary position. 15647e4937aSGao Xiang */ 15747e4937aSGao Xiang static int xattr_foreach(struct xattr_iter *it, 15847e4937aSGao Xiang const struct xattr_iter_handlers *op, 15947e4937aSGao Xiang unsigned int *tlimit) 16047e4937aSGao Xiang { 16147e4937aSGao Xiang struct erofs_xattr_entry entry; 162*eba67eb6SJingbo Xu struct super_block *sb = it->sb; 16347e4937aSGao Xiang unsigned int value_sz, processed, slice; 16447e4937aSGao Xiang int err; 16547e4937aSGao Xiang 166*eba67eb6SJingbo Xu /* 0. fixup blkaddr, pos */ 167*eba67eb6SJingbo Xu it->kaddr = erofs_bread(&it->buf, erofs_blknr(sb, it->pos), EROFS_KMAP); 168*eba67eb6SJingbo Xu if (IS_ERR(it->kaddr)) 169*eba67eb6SJingbo Xu return PTR_ERR(it->kaddr); 17047e4937aSGao Xiang 17147e4937aSGao Xiang /* 17247e4937aSGao Xiang * 1. read xattr entry to the memory, 17347e4937aSGao Xiang * since we do EROFS_XATTR_ALIGN 17447e4937aSGao Xiang * therefore entry should be in the page 17547e4937aSGao Xiang */ 176*eba67eb6SJingbo Xu entry = *(struct erofs_xattr_entry *) 177*eba67eb6SJingbo Xu (it->kaddr + erofs_blkoff(sb, it->pos)); 17847e4937aSGao Xiang if (tlimit) { 179b6796abdSGao Xiang unsigned int entry_sz = erofs_xattr_entry_size(&entry); 18047e4937aSGao Xiang 18147e4937aSGao Xiang /* xattr on-disk corruption: xattr entry beyond xattr_isize */ 1828d8a09b0SGao Xiang if (*tlimit < entry_sz) { 18347e4937aSGao Xiang DBG_BUGON(1); 18447e4937aSGao Xiang return -EFSCORRUPTED; 18547e4937aSGao Xiang } 18647e4937aSGao Xiang *tlimit -= entry_sz; 18747e4937aSGao Xiang } 18847e4937aSGao Xiang 189*eba67eb6SJingbo Xu it->pos += sizeof(struct erofs_xattr_entry); 19047e4937aSGao Xiang value_sz = le16_to_cpu(entry.e_value_size); 19147e4937aSGao Xiang 19247e4937aSGao Xiang /* handle entry */ 19347e4937aSGao Xiang err = op->entry(it, &entry); 19447e4937aSGao Xiang if (err) { 195*eba67eb6SJingbo Xu it->pos += entry.e_name_len + value_sz; 19647e4937aSGao Xiang goto out; 19747e4937aSGao Xiang } 19847e4937aSGao Xiang 199*eba67eb6SJingbo Xu /* 2. handle xattr name (pos will finally be at the end of name) */ 20047e4937aSGao Xiang processed = 0; 20147e4937aSGao Xiang 20247e4937aSGao Xiang while (processed < entry.e_name_len) { 203*eba67eb6SJingbo Xu it->kaddr = erofs_bread(&it->buf, erofs_blknr(sb, it->pos), 204*eba67eb6SJingbo Xu EROFS_KMAP); 205*eba67eb6SJingbo Xu if (IS_ERR(it->kaddr)) { 206*eba67eb6SJingbo Xu err = PTR_ERR(it->kaddr); 20747e4937aSGao Xiang goto out; 20847e4937aSGao Xiang } 20947e4937aSGao Xiang 210*eba67eb6SJingbo Xu slice = min_t(unsigned int, 211*eba67eb6SJingbo Xu sb->s_blocksize - erofs_blkoff(sb, it->pos), 21247e4937aSGao Xiang entry.e_name_len - processed); 21347e4937aSGao Xiang 21447e4937aSGao Xiang /* handle name */ 215*eba67eb6SJingbo Xu err = op->name(it, processed, 216*eba67eb6SJingbo Xu it->kaddr + erofs_blkoff(sb, it->pos), slice); 21747e4937aSGao Xiang if (err) { 218*eba67eb6SJingbo Xu it->pos += entry.e_name_len - processed + value_sz; 21947e4937aSGao Xiang goto out; 22047e4937aSGao Xiang } 22147e4937aSGao Xiang 222*eba67eb6SJingbo Xu it->pos += slice; 22347e4937aSGao Xiang processed += slice; 22447e4937aSGao Xiang } 22547e4937aSGao Xiang 22647e4937aSGao Xiang /* 3. handle xattr value */ 22747e4937aSGao Xiang processed = 0; 22847e4937aSGao Xiang 22947e4937aSGao Xiang if (op->alloc_buffer) { 23047e4937aSGao Xiang err = op->alloc_buffer(it, value_sz); 23147e4937aSGao Xiang if (err) { 232*eba67eb6SJingbo Xu it->pos += value_sz; 23347e4937aSGao Xiang goto out; 23447e4937aSGao Xiang } 23547e4937aSGao Xiang } 23647e4937aSGao Xiang 23747e4937aSGao Xiang while (processed < value_sz) { 238*eba67eb6SJingbo Xu it->kaddr = erofs_bread(&it->buf, erofs_blknr(sb, it->pos), 239*eba67eb6SJingbo Xu EROFS_KMAP); 240*eba67eb6SJingbo Xu if (IS_ERR(it->kaddr)) { 241*eba67eb6SJingbo Xu err = PTR_ERR(it->kaddr); 24247e4937aSGao Xiang goto out; 24347e4937aSGao Xiang } 24447e4937aSGao Xiang 245*eba67eb6SJingbo Xu slice = min_t(unsigned int, 246*eba67eb6SJingbo Xu sb->s_blocksize - erofs_blkoff(sb, it->pos), 24747e4937aSGao Xiang value_sz - processed); 248*eba67eb6SJingbo Xu op->value(it, processed, it->kaddr + erofs_blkoff(sb, it->pos), 249*eba67eb6SJingbo Xu slice); 250*eba67eb6SJingbo Xu it->pos += slice; 25147e4937aSGao Xiang processed += slice; 25247e4937aSGao Xiang } 25347e4937aSGao Xiang 25447e4937aSGao Xiang out: 25547e4937aSGao Xiang /* xattrs should be 4-byte aligned (on-disk constraint) */ 256*eba67eb6SJingbo Xu it->pos = EROFS_XATTR_ALIGN(it->pos); 25747e4937aSGao Xiang return err < 0 ? err : 0; 25847e4937aSGao Xiang } 25947e4937aSGao Xiang 26047e4937aSGao Xiang struct getxattr_iter { 26147e4937aSGao Xiang struct xattr_iter it; 26247e4937aSGao Xiang 26347e4937aSGao Xiang char *buffer; 26482bc1ef4SJingbo Xu int buffer_size, index, infix_len; 26547e4937aSGao Xiang struct qstr name; 26647e4937aSGao Xiang }; 26747e4937aSGao Xiang 26882bc1ef4SJingbo Xu static int erofs_xattr_long_entrymatch(struct getxattr_iter *it, 26982bc1ef4SJingbo Xu struct erofs_xattr_entry *entry) 27082bc1ef4SJingbo Xu { 27182bc1ef4SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(it->it.sb); 27282bc1ef4SJingbo Xu struct erofs_xattr_prefix_item *pf = sbi->xattr_prefixes + 27382bc1ef4SJingbo Xu (entry->e_name_index & EROFS_XATTR_LONG_PREFIX_MASK); 27482bc1ef4SJingbo Xu 27582bc1ef4SJingbo Xu if (pf >= sbi->xattr_prefixes + sbi->xattr_prefix_count) 27682bc1ef4SJingbo Xu return -ENOATTR; 27782bc1ef4SJingbo Xu 27882bc1ef4SJingbo Xu if (it->index != pf->prefix->base_index || 27982bc1ef4SJingbo Xu it->name.len != entry->e_name_len + pf->infix_len) 28082bc1ef4SJingbo Xu return -ENOATTR; 28182bc1ef4SJingbo Xu 28282bc1ef4SJingbo Xu if (memcmp(it->name.name, pf->prefix->infix, pf->infix_len)) 28382bc1ef4SJingbo Xu return -ENOATTR; 28482bc1ef4SJingbo Xu 28582bc1ef4SJingbo Xu it->infix_len = pf->infix_len; 28682bc1ef4SJingbo Xu return 0; 28782bc1ef4SJingbo Xu } 28882bc1ef4SJingbo Xu 28947e4937aSGao Xiang static int xattr_entrymatch(struct xattr_iter *_it, 29047e4937aSGao Xiang struct erofs_xattr_entry *entry) 29147e4937aSGao Xiang { 29247e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 29347e4937aSGao Xiang 29482bc1ef4SJingbo Xu /* should also match the infix for long name prefixes */ 29582bc1ef4SJingbo Xu if (entry->e_name_index & EROFS_XATTR_LONG_PREFIX) 29682bc1ef4SJingbo Xu return erofs_xattr_long_entrymatch(it, entry); 29782bc1ef4SJingbo Xu 29882bc1ef4SJingbo Xu if (it->index != entry->e_name_index || 29982bc1ef4SJingbo Xu it->name.len != entry->e_name_len) 30082bc1ef4SJingbo Xu return -ENOATTR; 30182bc1ef4SJingbo Xu it->infix_len = 0; 30282bc1ef4SJingbo Xu return 0; 30347e4937aSGao Xiang } 30447e4937aSGao Xiang 30547e4937aSGao Xiang static int xattr_namematch(struct xattr_iter *_it, 30647e4937aSGao Xiang unsigned int processed, char *buf, unsigned int len) 30747e4937aSGao Xiang { 30847e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 30947e4937aSGao Xiang 31082bc1ef4SJingbo Xu if (memcmp(buf, it->name.name + it->infix_len + processed, len)) 31182bc1ef4SJingbo Xu return -ENOATTR; 31282bc1ef4SJingbo Xu return 0; 31347e4937aSGao Xiang } 31447e4937aSGao Xiang 31547e4937aSGao Xiang static int xattr_checkbuffer(struct xattr_iter *_it, 31647e4937aSGao Xiang unsigned int value_sz) 31747e4937aSGao Xiang { 31847e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 31947e4937aSGao Xiang int err = it->buffer_size < value_sz ? -ERANGE : 0; 32047e4937aSGao Xiang 32147e4937aSGao Xiang it->buffer_size = value_sz; 32247e4937aSGao Xiang return !it->buffer ? 1 : err; 32347e4937aSGao Xiang } 32447e4937aSGao Xiang 32547e4937aSGao Xiang static void xattr_copyvalue(struct xattr_iter *_it, 32647e4937aSGao Xiang unsigned int processed, 32747e4937aSGao Xiang char *buf, unsigned int len) 32847e4937aSGao Xiang { 32947e4937aSGao Xiang struct getxattr_iter *it = container_of(_it, struct getxattr_iter, it); 33047e4937aSGao Xiang 33147e4937aSGao Xiang memcpy(it->buffer + processed, buf, len); 33247e4937aSGao Xiang } 33347e4937aSGao Xiang 33447e4937aSGao Xiang static const struct xattr_iter_handlers find_xattr_handlers = { 33547e4937aSGao Xiang .entry = xattr_entrymatch, 33647e4937aSGao Xiang .name = xattr_namematch, 33747e4937aSGao Xiang .alloc_buffer = xattr_checkbuffer, 33847e4937aSGao Xiang .value = xattr_copyvalue 33947e4937aSGao Xiang }; 34047e4937aSGao Xiang 34147e4937aSGao Xiang static int inline_getxattr(struct inode *inode, struct getxattr_iter *it) 34247e4937aSGao Xiang { 34347e4937aSGao Xiang int ret; 34447e4937aSGao Xiang unsigned int remaining; 34547e4937aSGao Xiang 34647e4937aSGao Xiang ret = inline_xattr_iter_begin(&it->it, inode); 34747e4937aSGao Xiang if (ret < 0) 34847e4937aSGao Xiang return ret; 34947e4937aSGao Xiang 35047e4937aSGao Xiang remaining = ret; 35147e4937aSGao Xiang while (remaining) { 35247e4937aSGao Xiang ret = xattr_foreach(&it->it, &find_xattr_handlers, &remaining); 35347e4937aSGao Xiang if (ret != -ENOATTR) 35447e4937aSGao Xiang break; 35547e4937aSGao Xiang } 35647e4937aSGao Xiang return ret ? ret : it->buffer_size; 35747e4937aSGao Xiang } 35847e4937aSGao Xiang 35947e4937aSGao Xiang static int shared_getxattr(struct inode *inode, struct getxattr_iter *it) 36047e4937aSGao Xiang { 361a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 362399f36d8SJingbo Xu struct super_block *const sb = it->it.sb; 363*eba67eb6SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(sb); 364*eba67eb6SJingbo Xu unsigned int i; 36547e4937aSGao Xiang int ret = -ENOATTR; 36647e4937aSGao Xiang 36747e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 368*eba67eb6SJingbo Xu it->it.pos = erofs_pos(sb, sbi->xattr_blkaddr) + 369*eba67eb6SJingbo Xu vi->xattr_shared_xattrs[i] * sizeof(__le32); 370*eba67eb6SJingbo Xu it->it.kaddr = erofs_bread(&it->it.buf, 371*eba67eb6SJingbo Xu erofs_blknr(sb, it->it.pos), EROFS_KMAP); 372bb88e8daSGao Xiang if (IS_ERR(it->it.kaddr)) 373bb88e8daSGao Xiang return PTR_ERR(it->it.kaddr); 37447e4937aSGao Xiang 37547e4937aSGao Xiang ret = xattr_foreach(&it->it, &find_xattr_handlers, NULL); 37647e4937aSGao Xiang if (ret != -ENOATTR) 37747e4937aSGao Xiang break; 37847e4937aSGao Xiang } 37947e4937aSGao Xiang return ret ? ret : it->buffer_size; 38047e4937aSGao Xiang } 38147e4937aSGao Xiang 38247e4937aSGao Xiang static bool erofs_xattr_user_list(struct dentry *dentry) 38347e4937aSGao Xiang { 384e6242465SGao Xiang return test_opt(&EROFS_SB(dentry->d_sb)->opt, XATTR_USER); 38547e4937aSGao Xiang } 38647e4937aSGao Xiang 38747e4937aSGao Xiang static bool erofs_xattr_trusted_list(struct dentry *dentry) 38847e4937aSGao Xiang { 38947e4937aSGao Xiang return capable(CAP_SYS_ADMIN); 39047e4937aSGao Xiang } 39147e4937aSGao Xiang 39247e4937aSGao Xiang int erofs_getxattr(struct inode *inode, int index, 39347e4937aSGao Xiang const char *name, 39447e4937aSGao Xiang void *buffer, size_t buffer_size) 39547e4937aSGao Xiang { 39647e4937aSGao Xiang int ret; 39747e4937aSGao Xiang struct getxattr_iter it; 39847e4937aSGao Xiang 3998d8a09b0SGao Xiang if (!name) 40047e4937aSGao Xiang return -EINVAL; 40147e4937aSGao Xiang 4026020ffe7SJingbo Xu ret = erofs_init_inode_xattrs(inode); 40347e4937aSGao Xiang if (ret) 40447e4937aSGao Xiang return ret; 40547e4937aSGao Xiang 40647e4937aSGao Xiang it.index = index; 40747e4937aSGao Xiang it.name.len = strlen(name); 40847e4937aSGao Xiang if (it.name.len > EROFS_NAME_LEN) 40947e4937aSGao Xiang return -ERANGE; 410bb88e8daSGao Xiang 4119c39ec0cSJingbo Xu it.it.sb = inode->i_sb; 412bb88e8daSGao Xiang it.it.buf = __EROFS_BUF_INITIALIZER; 4139c39ec0cSJingbo Xu erofs_init_metabuf(&it.it.buf, it.it.sb); 41447e4937aSGao Xiang it.name.name = name; 41547e4937aSGao Xiang 41647e4937aSGao Xiang it.buffer = buffer; 41747e4937aSGao Xiang it.buffer_size = buffer_size; 41847e4937aSGao Xiang 41947e4937aSGao Xiang ret = inline_getxattr(inode, &it); 42047e4937aSGao Xiang if (ret == -ENOATTR) 42147e4937aSGao Xiang ret = shared_getxattr(inode, &it); 422bb88e8daSGao Xiang erofs_put_metabuf(&it.it.buf); 42347e4937aSGao Xiang return ret; 42447e4937aSGao Xiang } 42547e4937aSGao Xiang 42647e4937aSGao Xiang static int erofs_xattr_generic_get(const struct xattr_handler *handler, 42747e4937aSGao Xiang struct dentry *unused, struct inode *inode, 42847e4937aSGao Xiang const char *name, void *buffer, size_t size) 42947e4937aSGao Xiang { 430b05f30bcSJingbo Xu if (handler->flags == EROFS_XATTR_INDEX_USER && 431b05f30bcSJingbo Xu !test_opt(&EROFS_I_SB(inode)->opt, XATTR_USER)) 43247e4937aSGao Xiang return -EOPNOTSUPP; 43347e4937aSGao Xiang 43447e4937aSGao Xiang return erofs_getxattr(inode, handler->flags, name, buffer, size); 43547e4937aSGao Xiang } 43647e4937aSGao Xiang 43747e4937aSGao Xiang const struct xattr_handler erofs_xattr_user_handler = { 43847e4937aSGao Xiang .prefix = XATTR_USER_PREFIX, 43947e4937aSGao Xiang .flags = EROFS_XATTR_INDEX_USER, 44047e4937aSGao Xiang .list = erofs_xattr_user_list, 44147e4937aSGao Xiang .get = erofs_xattr_generic_get, 44247e4937aSGao Xiang }; 44347e4937aSGao Xiang 44447e4937aSGao Xiang const struct xattr_handler erofs_xattr_trusted_handler = { 44547e4937aSGao Xiang .prefix = XATTR_TRUSTED_PREFIX, 44647e4937aSGao Xiang .flags = EROFS_XATTR_INDEX_TRUSTED, 44747e4937aSGao Xiang .list = erofs_xattr_trusted_list, 44847e4937aSGao Xiang .get = erofs_xattr_generic_get, 44947e4937aSGao Xiang }; 45047e4937aSGao Xiang 45147e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_SECURITY 45247e4937aSGao Xiang const struct xattr_handler __maybe_unused erofs_xattr_security_handler = { 45347e4937aSGao Xiang .prefix = XATTR_SECURITY_PREFIX, 45447e4937aSGao Xiang .flags = EROFS_XATTR_INDEX_SECURITY, 45547e4937aSGao Xiang .get = erofs_xattr_generic_get, 45647e4937aSGao Xiang }; 45747e4937aSGao Xiang #endif 45847e4937aSGao Xiang 45947e4937aSGao Xiang const struct xattr_handler *erofs_xattr_handlers[] = { 46047e4937aSGao Xiang &erofs_xattr_user_handler, 46147e4937aSGao Xiang &erofs_xattr_trusted_handler, 46247e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_SECURITY 46347e4937aSGao Xiang &erofs_xattr_security_handler, 46447e4937aSGao Xiang #endif 46547e4937aSGao Xiang NULL, 46647e4937aSGao Xiang }; 46747e4937aSGao Xiang 46847e4937aSGao Xiang struct listxattr_iter { 46947e4937aSGao Xiang struct xattr_iter it; 47047e4937aSGao Xiang 47147e4937aSGao Xiang struct dentry *dentry; 47247e4937aSGao Xiang char *buffer; 47347e4937aSGao Xiang int buffer_size, buffer_ofs; 47447e4937aSGao Xiang }; 47547e4937aSGao Xiang 47647e4937aSGao Xiang static int xattr_entrylist(struct xattr_iter *_it, 47747e4937aSGao Xiang struct erofs_xattr_entry *entry) 47847e4937aSGao Xiang { 47947e4937aSGao Xiang struct listxattr_iter *it = 48047e4937aSGao Xiang container_of(_it, struct listxattr_iter, it); 48182bc1ef4SJingbo Xu unsigned int base_index = entry->e_name_index; 48282bc1ef4SJingbo Xu unsigned int prefix_len, infix_len = 0; 48382bc1ef4SJingbo Xu const char *prefix, *infix = NULL; 48447e4937aSGao Xiang 48582bc1ef4SJingbo Xu if (entry->e_name_index & EROFS_XATTR_LONG_PREFIX) { 48682bc1ef4SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(_it->sb); 48782bc1ef4SJingbo Xu struct erofs_xattr_prefix_item *pf = sbi->xattr_prefixes + 48882bc1ef4SJingbo Xu (entry->e_name_index & EROFS_XATTR_LONG_PREFIX_MASK); 48947e4937aSGao Xiang 49082bc1ef4SJingbo Xu if (pf >= sbi->xattr_prefixes + sbi->xattr_prefix_count) 49182bc1ef4SJingbo Xu return 1; 49282bc1ef4SJingbo Xu infix = pf->prefix->infix; 49382bc1ef4SJingbo Xu infix_len = pf->infix_len; 49482bc1ef4SJingbo Xu base_index = pf->prefix->base_index; 49582bc1ef4SJingbo Xu } 49682bc1ef4SJingbo Xu 49761d325dcSLinus Torvalds prefix = erofs_xattr_prefix(base_index, it->dentry); 498a5488f29SChristian Brauner if (!prefix) 49947e4937aSGao Xiang return 1; 50047e4937aSGao Xiang prefix_len = strlen(prefix); 50147e4937aSGao Xiang 50247e4937aSGao Xiang if (!it->buffer) { 50382bc1ef4SJingbo Xu it->buffer_ofs += prefix_len + infix_len + 50482bc1ef4SJingbo Xu entry->e_name_len + 1; 50547e4937aSGao Xiang return 1; 50647e4937aSGao Xiang } 50747e4937aSGao Xiang 50882bc1ef4SJingbo Xu if (it->buffer_ofs + prefix_len + infix_len + 50947e4937aSGao Xiang + entry->e_name_len + 1 > it->buffer_size) 51047e4937aSGao Xiang return -ERANGE; 51147e4937aSGao Xiang 51247e4937aSGao Xiang memcpy(it->buffer + it->buffer_ofs, prefix, prefix_len); 51382bc1ef4SJingbo Xu memcpy(it->buffer + it->buffer_ofs + prefix_len, infix, infix_len); 51482bc1ef4SJingbo Xu it->buffer_ofs += prefix_len + infix_len; 51547e4937aSGao Xiang return 0; 51647e4937aSGao Xiang } 51747e4937aSGao Xiang 51847e4937aSGao Xiang static int xattr_namelist(struct xattr_iter *_it, 51947e4937aSGao Xiang unsigned int processed, char *buf, unsigned int len) 52047e4937aSGao Xiang { 52147e4937aSGao Xiang struct listxattr_iter *it = 52247e4937aSGao Xiang container_of(_it, struct listxattr_iter, it); 52347e4937aSGao Xiang 52447e4937aSGao Xiang memcpy(it->buffer + it->buffer_ofs, buf, len); 52547e4937aSGao Xiang it->buffer_ofs += len; 52647e4937aSGao Xiang return 0; 52747e4937aSGao Xiang } 52847e4937aSGao Xiang 52947e4937aSGao Xiang static int xattr_skipvalue(struct xattr_iter *_it, 53047e4937aSGao Xiang unsigned int value_sz) 53147e4937aSGao Xiang { 53247e4937aSGao Xiang struct listxattr_iter *it = 53347e4937aSGao Xiang container_of(_it, struct listxattr_iter, it); 53447e4937aSGao Xiang 53547e4937aSGao Xiang it->buffer[it->buffer_ofs++] = '\0'; 53647e4937aSGao Xiang return 1; 53747e4937aSGao Xiang } 53847e4937aSGao Xiang 53947e4937aSGao Xiang static const struct xattr_iter_handlers list_xattr_handlers = { 54047e4937aSGao Xiang .entry = xattr_entrylist, 54147e4937aSGao Xiang .name = xattr_namelist, 54247e4937aSGao Xiang .alloc_buffer = xattr_skipvalue, 54347e4937aSGao Xiang .value = NULL 54447e4937aSGao Xiang }; 54547e4937aSGao Xiang 54647e4937aSGao Xiang static int inline_listxattr(struct listxattr_iter *it) 54747e4937aSGao Xiang { 54847e4937aSGao Xiang int ret; 54947e4937aSGao Xiang unsigned int remaining; 55047e4937aSGao Xiang 55147e4937aSGao Xiang ret = inline_xattr_iter_begin(&it->it, d_inode(it->dentry)); 55247e4937aSGao Xiang if (ret < 0) 55347e4937aSGao Xiang return ret; 55447e4937aSGao Xiang 55547e4937aSGao Xiang remaining = ret; 55647e4937aSGao Xiang while (remaining) { 55747e4937aSGao Xiang ret = xattr_foreach(&it->it, &list_xattr_handlers, &remaining); 55847e4937aSGao Xiang if (ret) 55947e4937aSGao Xiang break; 56047e4937aSGao Xiang } 56147e4937aSGao Xiang return ret ? ret : it->buffer_ofs; 56247e4937aSGao Xiang } 56347e4937aSGao Xiang 56447e4937aSGao Xiang static int shared_listxattr(struct listxattr_iter *it) 56547e4937aSGao Xiang { 56647e4937aSGao Xiang struct inode *const inode = d_inode(it->dentry); 567a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 568399f36d8SJingbo Xu struct super_block *const sb = it->it.sb; 569*eba67eb6SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(sb); 570*eba67eb6SJingbo Xu unsigned int i; 57147e4937aSGao Xiang int ret = 0; 57247e4937aSGao Xiang 57347e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 574*eba67eb6SJingbo Xu it->it.pos = erofs_pos(sb, sbi->xattr_blkaddr) + 575*eba67eb6SJingbo Xu vi->xattr_shared_xattrs[i] * sizeof(__le32); 576*eba67eb6SJingbo Xu it->it.kaddr = erofs_bread(&it->it.buf, 577*eba67eb6SJingbo Xu erofs_blknr(sb, it->it.pos), EROFS_KMAP); 578bb88e8daSGao Xiang if (IS_ERR(it->it.kaddr)) 579bb88e8daSGao Xiang return PTR_ERR(it->it.kaddr); 58047e4937aSGao Xiang 58147e4937aSGao Xiang ret = xattr_foreach(&it->it, &list_xattr_handlers, NULL); 58247e4937aSGao Xiang if (ret) 58347e4937aSGao Xiang break; 58447e4937aSGao Xiang } 58547e4937aSGao Xiang return ret ? ret : it->buffer_ofs; 58647e4937aSGao Xiang } 58747e4937aSGao Xiang 58847e4937aSGao Xiang ssize_t erofs_listxattr(struct dentry *dentry, 58947e4937aSGao Xiang char *buffer, size_t buffer_size) 59047e4937aSGao Xiang { 59147e4937aSGao Xiang int ret; 59247e4937aSGao Xiang struct listxattr_iter it; 59347e4937aSGao Xiang 5946020ffe7SJingbo Xu ret = erofs_init_inode_xattrs(d_inode(dentry)); 595926d1650SGao Xiang if (ret == -ENOATTR) 596926d1650SGao Xiang return 0; 59747e4937aSGao Xiang if (ret) 59847e4937aSGao Xiang return ret; 59947e4937aSGao Xiang 6009c39ec0cSJingbo Xu it.it.sb = dentry->d_sb; 601bb88e8daSGao Xiang it.it.buf = __EROFS_BUF_INITIALIZER; 6029c39ec0cSJingbo Xu erofs_init_metabuf(&it.it.buf, it.it.sb); 60347e4937aSGao Xiang it.dentry = dentry; 60447e4937aSGao Xiang it.buffer = buffer; 60547e4937aSGao Xiang it.buffer_size = buffer_size; 60647e4937aSGao Xiang it.buffer_ofs = 0; 60747e4937aSGao Xiang 60847e4937aSGao Xiang ret = inline_listxattr(&it); 609bb88e8daSGao Xiang if (ret >= 0 || ret == -ENOATTR) 610bb88e8daSGao Xiang ret = shared_listxattr(&it); 611bb88e8daSGao Xiang erofs_put_metabuf(&it.it.buf); 61247e4937aSGao Xiang return ret; 61347e4937aSGao Xiang } 61447e4937aSGao Xiang 6159e382914SJingbo Xu void erofs_xattr_prefixes_cleanup(struct super_block *sb) 6169e382914SJingbo Xu { 6179e382914SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(sb); 6189e382914SJingbo Xu int i; 6199e382914SJingbo Xu 6209e382914SJingbo Xu if (sbi->xattr_prefixes) { 6219e382914SJingbo Xu for (i = 0; i < sbi->xattr_prefix_count; i++) 6229e382914SJingbo Xu kfree(sbi->xattr_prefixes[i].prefix); 6239e382914SJingbo Xu kfree(sbi->xattr_prefixes); 6249e382914SJingbo Xu sbi->xattr_prefixes = NULL; 6259e382914SJingbo Xu } 6269e382914SJingbo Xu } 6279e382914SJingbo Xu 6289e382914SJingbo Xu int erofs_xattr_prefixes_init(struct super_block *sb) 6299e382914SJingbo Xu { 6309e382914SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(sb); 6319e382914SJingbo Xu struct erofs_buf buf = __EROFS_BUF_INITIALIZER; 6329e382914SJingbo Xu erofs_off_t pos = (erofs_off_t)sbi->xattr_prefix_start << 2; 6339e382914SJingbo Xu struct erofs_xattr_prefix_item *pfs; 6349e382914SJingbo Xu int ret = 0, i, len; 6359e382914SJingbo Xu 6369e382914SJingbo Xu if (!sbi->xattr_prefix_count) 6379e382914SJingbo Xu return 0; 6389e382914SJingbo Xu 6399e382914SJingbo Xu pfs = kzalloc(sbi->xattr_prefix_count * sizeof(*pfs), GFP_KERNEL); 6409e382914SJingbo Xu if (!pfs) 6419e382914SJingbo Xu return -ENOMEM; 6429e382914SJingbo Xu 6430a17567bSJingbo Xu if (sbi->packed_inode) 6449e382914SJingbo Xu buf.inode = sbi->packed_inode; 6459e382914SJingbo Xu else 6469e382914SJingbo Xu erofs_init_metabuf(&buf, sb); 6479e382914SJingbo Xu 6489e382914SJingbo Xu for (i = 0; i < sbi->xattr_prefix_count; i++) { 6499e382914SJingbo Xu void *ptr = erofs_read_metadata(sb, &buf, &pos, &len); 6509e382914SJingbo Xu 6519e382914SJingbo Xu if (IS_ERR(ptr)) { 6529e382914SJingbo Xu ret = PTR_ERR(ptr); 6539e382914SJingbo Xu break; 6549e382914SJingbo Xu } else if (len < sizeof(*pfs->prefix) || 6559e382914SJingbo Xu len > EROFS_NAME_LEN + sizeof(*pfs->prefix)) { 6569e382914SJingbo Xu kfree(ptr); 6579e382914SJingbo Xu ret = -EFSCORRUPTED; 6589e382914SJingbo Xu break; 6599e382914SJingbo Xu } 6609e382914SJingbo Xu pfs[i].prefix = ptr; 6619e382914SJingbo Xu pfs[i].infix_len = len - sizeof(struct erofs_xattr_long_prefix); 6629e382914SJingbo Xu } 6639e382914SJingbo Xu 6649e382914SJingbo Xu erofs_put_metabuf(&buf); 6659e382914SJingbo Xu sbi->xattr_prefixes = pfs; 6669e382914SJingbo Xu if (ret) 6679e382914SJingbo Xu erofs_xattr_prefixes_cleanup(sb); 6689e382914SJingbo Xu return ret; 6699e382914SJingbo Xu } 6709e382914SJingbo Xu 67147e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_POSIX_ACL 6720cad6246SMiklos Szeredi struct posix_acl *erofs_get_acl(struct inode *inode, int type, bool rcu) 67347e4937aSGao Xiang { 67447e4937aSGao Xiang struct posix_acl *acl; 67547e4937aSGao Xiang int prefix, rc; 67647e4937aSGao Xiang char *value = NULL; 67747e4937aSGao Xiang 6780cad6246SMiklos Szeredi if (rcu) 6790cad6246SMiklos Szeredi return ERR_PTR(-ECHILD); 6800cad6246SMiklos Szeredi 68147e4937aSGao Xiang switch (type) { 68247e4937aSGao Xiang case ACL_TYPE_ACCESS: 68347e4937aSGao Xiang prefix = EROFS_XATTR_INDEX_POSIX_ACL_ACCESS; 68447e4937aSGao Xiang break; 68547e4937aSGao Xiang case ACL_TYPE_DEFAULT: 68647e4937aSGao Xiang prefix = EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT; 68747e4937aSGao Xiang break; 68847e4937aSGao Xiang default: 68947e4937aSGao Xiang return ERR_PTR(-EINVAL); 69047e4937aSGao Xiang } 69147e4937aSGao Xiang 69247e4937aSGao Xiang rc = erofs_getxattr(inode, prefix, "", NULL, 0); 69347e4937aSGao Xiang if (rc > 0) { 69447e4937aSGao Xiang value = kmalloc(rc, GFP_KERNEL); 69547e4937aSGao Xiang if (!value) 69647e4937aSGao Xiang return ERR_PTR(-ENOMEM); 69747e4937aSGao Xiang rc = erofs_getxattr(inode, prefix, "", value, rc); 69847e4937aSGao Xiang } 69947e4937aSGao Xiang 70047e4937aSGao Xiang if (rc == -ENOATTR) 70147e4937aSGao Xiang acl = NULL; 70247e4937aSGao Xiang else if (rc < 0) 70347e4937aSGao Xiang acl = ERR_PTR(rc); 70447e4937aSGao Xiang else 70547e4937aSGao Xiang acl = posix_acl_from_xattr(&init_user_ns, value, rc); 70647e4937aSGao Xiang kfree(value); 70747e4937aSGao Xiang return acl; 70847e4937aSGao Xiang } 70947e4937aSGao Xiang #endif 710