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 10*8e823961SJingbo Xu struct erofs_xattr_iter { 1147e4937aSGao Xiang struct super_block *sb; 12bb88e8daSGao Xiang struct erofs_buf buf; 13eba67eb6SJingbo Xu erofs_off_t pos; 1447e4937aSGao Xiang void *kaddr; 15*8e823961SJingbo Xu 16*8e823961SJingbo Xu char *buffer; 17*8e823961SJingbo Xu int buffer_size, buffer_ofs; 18*8e823961SJingbo Xu 19*8e823961SJingbo Xu /* getxattr */ 20*8e823961SJingbo Xu int index, infix_len; 21*8e823961SJingbo Xu struct qstr name; 22*8e823961SJingbo Xu 23*8e823961SJingbo Xu /* listxattr */ 24*8e823961SJingbo Xu struct dentry *dentry; 2547e4937aSGao Xiang }; 2647e4937aSGao Xiang 276020ffe7SJingbo Xu static int erofs_init_inode_xattrs(struct inode *inode) 2847e4937aSGao Xiang { 29a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 30*8e823961SJingbo Xu struct erofs_xattr_iter it; 3147e4937aSGao Xiang unsigned int i; 3247e4937aSGao Xiang struct erofs_xattr_ibody_header *ih; 33b780d3fcSGao Xiang struct super_block *sb = inode->i_sb; 3447e4937aSGao Xiang int ret = 0; 3547e4937aSGao Xiang 3647e4937aSGao Xiang /* the most case is that xattrs of this inode are initialized. */ 37ce063129SGao Xiang if (test_bit(EROFS_I_EA_INITED_BIT, &vi->flags)) { 38ce063129SGao Xiang /* 39ce063129SGao Xiang * paired with smp_mb() at the end of the function to ensure 40ce063129SGao Xiang * fields will only be observed after the bit is set. 41ce063129SGao Xiang */ 42ce063129SGao Xiang smp_mb(); 4347e4937aSGao Xiang return 0; 44ce063129SGao Xiang } 4547e4937aSGao Xiang 46a5876e24SGao Xiang if (wait_on_bit_lock(&vi->flags, EROFS_I_BL_XATTR_BIT, TASK_KILLABLE)) 4747e4937aSGao Xiang return -ERESTARTSYS; 4847e4937aSGao Xiang 4947e4937aSGao Xiang /* someone has initialized xattrs for us? */ 50a5876e24SGao Xiang if (test_bit(EROFS_I_EA_INITED_BIT, &vi->flags)) 5147e4937aSGao Xiang goto out_unlock; 5247e4937aSGao Xiang 5347e4937aSGao Xiang /* 5447e4937aSGao Xiang * bypass all xattr operations if ->xattr_isize is not greater than 5547e4937aSGao Xiang * sizeof(struct erofs_xattr_ibody_header), in detail: 5647e4937aSGao Xiang * 1) it is not enough to contain erofs_xattr_ibody_header then 5747e4937aSGao Xiang * ->xattr_isize should be 0 (it means no xattr); 5847e4937aSGao Xiang * 2) it is just to contain erofs_xattr_ibody_header, which is on-disk 5947e4937aSGao Xiang * undefined right now (maybe use later with some new sb feature). 6047e4937aSGao Xiang */ 6147e4937aSGao Xiang if (vi->xattr_isize == sizeof(struct erofs_xattr_ibody_header)) { 62b780d3fcSGao Xiang erofs_err(sb, 634f761fa2SGao Xiang "xattr_isize %d of nid %llu is not supported yet", 6447e4937aSGao Xiang vi->xattr_isize, vi->nid); 6547e4937aSGao Xiang ret = -EOPNOTSUPP; 6647e4937aSGao Xiang goto out_unlock; 6747e4937aSGao Xiang } else if (vi->xattr_isize < sizeof(struct erofs_xattr_ibody_header)) { 688d8a09b0SGao Xiang if (vi->xattr_isize) { 69b780d3fcSGao Xiang erofs_err(sb, "bogus xattr ibody @ nid %llu", vi->nid); 7047e4937aSGao Xiang DBG_BUGON(1); 7147e4937aSGao Xiang ret = -EFSCORRUPTED; 7247e4937aSGao Xiang goto out_unlock; /* xattr ondisk layout error */ 7347e4937aSGao Xiang } 7447e4937aSGao Xiang ret = -ENOATTR; 7547e4937aSGao Xiang goto out_unlock; 7647e4937aSGao Xiang } 7747e4937aSGao Xiang 78bb88e8daSGao Xiang it.buf = __EROFS_BUF_INITIALIZER; 799c39ec0cSJingbo Xu erofs_init_metabuf(&it.buf, sb); 80eba67eb6SJingbo Xu it.pos = erofs_iloc(inode) + vi->inode_isize; 8147e4937aSGao Xiang 82bb88e8daSGao Xiang /* read in shared xattr array (non-atomic, see kmalloc below) */ 83eba67eb6SJingbo Xu it.kaddr = erofs_bread(&it.buf, erofs_blknr(sb, it.pos), EROFS_KMAP); 84bb88e8daSGao Xiang if (IS_ERR(it.kaddr)) { 85bb88e8daSGao Xiang ret = PTR_ERR(it.kaddr); 8647e4937aSGao Xiang goto out_unlock; 8747e4937aSGao Xiang } 8847e4937aSGao Xiang 89eba67eb6SJingbo Xu ih = it.kaddr + erofs_blkoff(sb, it.pos); 9047e4937aSGao Xiang vi->xattr_shared_count = ih->h_shared_count; 9147e4937aSGao Xiang vi->xattr_shared_xattrs = kmalloc_array(vi->xattr_shared_count, 9247e4937aSGao Xiang sizeof(uint), GFP_KERNEL); 9347e4937aSGao Xiang if (!vi->xattr_shared_xattrs) { 94bb88e8daSGao Xiang erofs_put_metabuf(&it.buf); 9547e4937aSGao Xiang ret = -ENOMEM; 9647e4937aSGao Xiang goto out_unlock; 9747e4937aSGao Xiang } 9847e4937aSGao Xiang 9947e4937aSGao Xiang /* let's skip ibody header */ 100eba67eb6SJingbo Xu it.pos += sizeof(struct erofs_xattr_ibody_header); 10147e4937aSGao Xiang 10247e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 103eba67eb6SJingbo Xu it.kaddr = erofs_bread(&it.buf, erofs_blknr(sb, it.pos), 104eba67eb6SJingbo Xu EROFS_KMAP); 105bb88e8daSGao Xiang if (IS_ERR(it.kaddr)) { 10647e4937aSGao Xiang kfree(vi->xattr_shared_xattrs); 10747e4937aSGao Xiang vi->xattr_shared_xattrs = NULL; 108bb88e8daSGao Xiang ret = PTR_ERR(it.kaddr); 10947e4937aSGao Xiang goto out_unlock; 11047e4937aSGao Xiang } 111eba67eb6SJingbo Xu vi->xattr_shared_xattrs[i] = le32_to_cpu(*(__le32 *) 112eba67eb6SJingbo Xu (it.kaddr + erofs_blkoff(sb, it.pos))); 113eba67eb6SJingbo Xu it.pos += sizeof(__le32); 11447e4937aSGao Xiang } 115bb88e8daSGao Xiang erofs_put_metabuf(&it.buf); 11647e4937aSGao Xiang 117ce063129SGao Xiang /* paired with smp_mb() at the beginning of the function. */ 118ce063129SGao Xiang smp_mb(); 119a5876e24SGao Xiang set_bit(EROFS_I_EA_INITED_BIT, &vi->flags); 12047e4937aSGao Xiang 12147e4937aSGao Xiang out_unlock: 122a5876e24SGao Xiang clear_and_wake_up_bit(EROFS_I_BL_XATTR_BIT, &vi->flags); 12347e4937aSGao Xiang return ret; 12447e4937aSGao Xiang } 12547e4937aSGao Xiang 12647e4937aSGao Xiang /* 12747e4937aSGao Xiang * the general idea for these return values is 12847e4937aSGao Xiang * if 0 is returned, go on processing the current xattr; 12947e4937aSGao Xiang * 1 (> 0) is returned, skip this round to process the next xattr; 13047e4937aSGao Xiang * -err (< 0) is returned, an error (maybe ENOXATTR) occurred 13147e4937aSGao Xiang * and need to be handled 13247e4937aSGao Xiang */ 13347e4937aSGao Xiang struct xattr_iter_handlers { 134*8e823961SJingbo Xu int (*entry)(struct erofs_xattr_iter *it, struct erofs_xattr_entry *entry); 135*8e823961SJingbo Xu int (*name)(struct erofs_xattr_iter *it, unsigned int processed, char *buf, 13647e4937aSGao Xiang unsigned int len); 137*8e823961SJingbo Xu int (*alloc_buffer)(struct erofs_xattr_iter *it, unsigned int value_sz); 138*8e823961SJingbo Xu void (*value)(struct erofs_xattr_iter *it, unsigned int processed, char *buf, 13947e4937aSGao Xiang unsigned int len); 14047e4937aSGao Xiang }; 14147e4937aSGao Xiang 142*8e823961SJingbo Xu static int inline_xattr_iter_begin(struct erofs_xattr_iter *it, 14347e4937aSGao Xiang struct inode *inode) 14447e4937aSGao Xiang { 145a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 146eba67eb6SJingbo Xu unsigned int xattr_header_sz; 14747e4937aSGao Xiang 148399f36d8SJingbo Xu xattr_header_sz = sizeof(struct erofs_xattr_ibody_header) + 149399f36d8SJingbo Xu sizeof(u32) * vi->xattr_shared_count; 1508d8a09b0SGao Xiang if (xattr_header_sz >= vi->xattr_isize) { 15147e4937aSGao Xiang DBG_BUGON(xattr_header_sz > vi->xattr_isize); 15247e4937aSGao Xiang return -ENOATTR; 15347e4937aSGao Xiang } 15447e4937aSGao Xiang 155eba67eb6SJingbo Xu it->pos = erofs_iloc(inode) + vi->inode_isize + xattr_header_sz; 156eba67eb6SJingbo Xu it->kaddr = erofs_bread(&it->buf, erofs_blknr(it->sb, it->pos), 157eba67eb6SJingbo Xu EROFS_KMAP); 158bb88e8daSGao Xiang if (IS_ERR(it->kaddr)) 159bb88e8daSGao Xiang return PTR_ERR(it->kaddr); 16047e4937aSGao Xiang return vi->xattr_isize - xattr_header_sz; 16147e4937aSGao Xiang } 16247e4937aSGao Xiang 16347e4937aSGao Xiang /* 16447e4937aSGao Xiang * Regardless of success or failure, `xattr_foreach' will end up with 165eba67eb6SJingbo Xu * `pos' pointing to the next xattr item rather than an arbitrary position. 16647e4937aSGao Xiang */ 167*8e823961SJingbo Xu static int xattr_foreach(struct erofs_xattr_iter *it, 16847e4937aSGao Xiang const struct xattr_iter_handlers *op, 16947e4937aSGao Xiang unsigned int *tlimit) 17047e4937aSGao Xiang { 17147e4937aSGao Xiang struct erofs_xattr_entry entry; 172eba67eb6SJingbo Xu struct super_block *sb = it->sb; 17347e4937aSGao Xiang unsigned int value_sz, processed, slice; 17447e4937aSGao Xiang int err; 17547e4937aSGao Xiang 176eba67eb6SJingbo Xu /* 0. fixup blkaddr, pos */ 177eba67eb6SJingbo Xu it->kaddr = erofs_bread(&it->buf, erofs_blknr(sb, it->pos), EROFS_KMAP); 178eba67eb6SJingbo Xu if (IS_ERR(it->kaddr)) 179eba67eb6SJingbo Xu return PTR_ERR(it->kaddr); 18047e4937aSGao Xiang 18147e4937aSGao Xiang /* 18247e4937aSGao Xiang * 1. read xattr entry to the memory, 18347e4937aSGao Xiang * since we do EROFS_XATTR_ALIGN 18447e4937aSGao Xiang * therefore entry should be in the page 18547e4937aSGao Xiang */ 186eba67eb6SJingbo Xu entry = *(struct erofs_xattr_entry *) 187eba67eb6SJingbo Xu (it->kaddr + erofs_blkoff(sb, it->pos)); 18847e4937aSGao Xiang if (tlimit) { 189b6796abdSGao Xiang unsigned int entry_sz = erofs_xattr_entry_size(&entry); 19047e4937aSGao Xiang 19147e4937aSGao Xiang /* xattr on-disk corruption: xattr entry beyond xattr_isize */ 1928d8a09b0SGao Xiang if (*tlimit < entry_sz) { 19347e4937aSGao Xiang DBG_BUGON(1); 19447e4937aSGao Xiang return -EFSCORRUPTED; 19547e4937aSGao Xiang } 19647e4937aSGao Xiang *tlimit -= entry_sz; 19747e4937aSGao Xiang } 19847e4937aSGao Xiang 199eba67eb6SJingbo Xu it->pos += sizeof(struct erofs_xattr_entry); 20047e4937aSGao Xiang value_sz = le16_to_cpu(entry.e_value_size); 20147e4937aSGao Xiang 20247e4937aSGao Xiang /* handle entry */ 20347e4937aSGao Xiang err = op->entry(it, &entry); 20447e4937aSGao Xiang if (err) { 205eba67eb6SJingbo Xu it->pos += entry.e_name_len + value_sz; 20647e4937aSGao Xiang goto out; 20747e4937aSGao Xiang } 20847e4937aSGao Xiang 209eba67eb6SJingbo Xu /* 2. handle xattr name (pos will finally be at the end of name) */ 21047e4937aSGao Xiang processed = 0; 21147e4937aSGao Xiang 21247e4937aSGao Xiang while (processed < entry.e_name_len) { 213eba67eb6SJingbo Xu it->kaddr = erofs_bread(&it->buf, erofs_blknr(sb, it->pos), 214eba67eb6SJingbo Xu EROFS_KMAP); 215eba67eb6SJingbo Xu if (IS_ERR(it->kaddr)) { 216eba67eb6SJingbo Xu err = PTR_ERR(it->kaddr); 21747e4937aSGao Xiang goto out; 21847e4937aSGao Xiang } 21947e4937aSGao Xiang 220eba67eb6SJingbo Xu slice = min_t(unsigned int, 221eba67eb6SJingbo Xu sb->s_blocksize - erofs_blkoff(sb, it->pos), 22247e4937aSGao Xiang entry.e_name_len - processed); 22347e4937aSGao Xiang 22447e4937aSGao Xiang /* handle name */ 225eba67eb6SJingbo Xu err = op->name(it, processed, 226eba67eb6SJingbo Xu it->kaddr + erofs_blkoff(sb, it->pos), slice); 22747e4937aSGao Xiang if (err) { 228eba67eb6SJingbo Xu it->pos += entry.e_name_len - processed + value_sz; 22947e4937aSGao Xiang goto out; 23047e4937aSGao Xiang } 23147e4937aSGao Xiang 232eba67eb6SJingbo Xu it->pos += slice; 23347e4937aSGao Xiang processed += slice; 23447e4937aSGao Xiang } 23547e4937aSGao Xiang 23647e4937aSGao Xiang /* 3. handle xattr value */ 23747e4937aSGao Xiang processed = 0; 23847e4937aSGao Xiang 23947e4937aSGao Xiang if (op->alloc_buffer) { 24047e4937aSGao Xiang err = op->alloc_buffer(it, value_sz); 24147e4937aSGao Xiang if (err) { 242eba67eb6SJingbo Xu it->pos += value_sz; 24347e4937aSGao Xiang goto out; 24447e4937aSGao Xiang } 24547e4937aSGao Xiang } 24647e4937aSGao Xiang 24747e4937aSGao Xiang while (processed < value_sz) { 248eba67eb6SJingbo Xu it->kaddr = erofs_bread(&it->buf, erofs_blknr(sb, it->pos), 249eba67eb6SJingbo Xu EROFS_KMAP); 250eba67eb6SJingbo Xu if (IS_ERR(it->kaddr)) { 251eba67eb6SJingbo Xu err = PTR_ERR(it->kaddr); 25247e4937aSGao Xiang goto out; 25347e4937aSGao Xiang } 25447e4937aSGao Xiang 255eba67eb6SJingbo Xu slice = min_t(unsigned int, 256eba67eb6SJingbo Xu sb->s_blocksize - erofs_blkoff(sb, it->pos), 25747e4937aSGao Xiang value_sz - processed); 258eba67eb6SJingbo Xu op->value(it, processed, it->kaddr + erofs_blkoff(sb, it->pos), 259eba67eb6SJingbo Xu slice); 260eba67eb6SJingbo Xu it->pos += slice; 26147e4937aSGao Xiang processed += slice; 26247e4937aSGao Xiang } 26347e4937aSGao Xiang 26447e4937aSGao Xiang out: 26547e4937aSGao Xiang /* xattrs should be 4-byte aligned (on-disk constraint) */ 266eba67eb6SJingbo Xu it->pos = EROFS_XATTR_ALIGN(it->pos); 26747e4937aSGao Xiang return err < 0 ? err : 0; 26847e4937aSGao Xiang } 26947e4937aSGao Xiang 270*8e823961SJingbo Xu static int erofs_xattr_long_entrymatch(struct erofs_xattr_iter *it, 27182bc1ef4SJingbo Xu struct erofs_xattr_entry *entry) 27282bc1ef4SJingbo Xu { 273*8e823961SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(it->sb); 27482bc1ef4SJingbo Xu struct erofs_xattr_prefix_item *pf = sbi->xattr_prefixes + 27582bc1ef4SJingbo Xu (entry->e_name_index & EROFS_XATTR_LONG_PREFIX_MASK); 27682bc1ef4SJingbo Xu 27782bc1ef4SJingbo Xu if (pf >= sbi->xattr_prefixes + sbi->xattr_prefix_count) 27882bc1ef4SJingbo Xu return -ENOATTR; 27982bc1ef4SJingbo Xu 28082bc1ef4SJingbo Xu if (it->index != pf->prefix->base_index || 28182bc1ef4SJingbo Xu it->name.len != entry->e_name_len + pf->infix_len) 28282bc1ef4SJingbo Xu return -ENOATTR; 28382bc1ef4SJingbo Xu 28482bc1ef4SJingbo Xu if (memcmp(it->name.name, pf->prefix->infix, pf->infix_len)) 28582bc1ef4SJingbo Xu return -ENOATTR; 28682bc1ef4SJingbo Xu 28782bc1ef4SJingbo Xu it->infix_len = pf->infix_len; 28882bc1ef4SJingbo Xu return 0; 28982bc1ef4SJingbo Xu } 29082bc1ef4SJingbo Xu 291*8e823961SJingbo Xu static int xattr_entrymatch(struct erofs_xattr_iter *it, 29247e4937aSGao Xiang struct erofs_xattr_entry *entry) 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 305*8e823961SJingbo Xu static int xattr_namematch(struct erofs_xattr_iter *it, 30647e4937aSGao Xiang unsigned int processed, char *buf, unsigned int len) 30747e4937aSGao Xiang { 30882bc1ef4SJingbo Xu if (memcmp(buf, it->name.name + it->infix_len + processed, len)) 30982bc1ef4SJingbo Xu return -ENOATTR; 31082bc1ef4SJingbo Xu return 0; 31147e4937aSGao Xiang } 31247e4937aSGao Xiang 313*8e823961SJingbo Xu static int xattr_checkbuffer(struct erofs_xattr_iter *it, 31447e4937aSGao Xiang unsigned int value_sz) 31547e4937aSGao Xiang { 31647e4937aSGao Xiang int err = it->buffer_size < value_sz ? -ERANGE : 0; 31747e4937aSGao Xiang 31847e4937aSGao Xiang it->buffer_size = value_sz; 31947e4937aSGao Xiang return !it->buffer ? 1 : err; 32047e4937aSGao Xiang } 32147e4937aSGao Xiang 322*8e823961SJingbo Xu static void xattr_copyvalue(struct erofs_xattr_iter *it, 32347e4937aSGao Xiang unsigned int processed, 32447e4937aSGao Xiang char *buf, unsigned int len) 32547e4937aSGao Xiang { 32647e4937aSGao Xiang memcpy(it->buffer + processed, buf, len); 32747e4937aSGao Xiang } 32847e4937aSGao Xiang 32947e4937aSGao Xiang static const struct xattr_iter_handlers find_xattr_handlers = { 33047e4937aSGao Xiang .entry = xattr_entrymatch, 33147e4937aSGao Xiang .name = xattr_namematch, 33247e4937aSGao Xiang .alloc_buffer = xattr_checkbuffer, 33347e4937aSGao Xiang .value = xattr_copyvalue 33447e4937aSGao Xiang }; 33547e4937aSGao Xiang 336*8e823961SJingbo Xu static int inline_getxattr(struct inode *inode, struct erofs_xattr_iter *it) 33747e4937aSGao Xiang { 33847e4937aSGao Xiang int ret; 33947e4937aSGao Xiang unsigned int remaining; 34047e4937aSGao Xiang 341*8e823961SJingbo Xu ret = inline_xattr_iter_begin(it, inode); 34247e4937aSGao Xiang if (ret < 0) 34347e4937aSGao Xiang return ret; 34447e4937aSGao Xiang 34547e4937aSGao Xiang remaining = ret; 34647e4937aSGao Xiang while (remaining) { 347*8e823961SJingbo Xu ret = xattr_foreach(it, &find_xattr_handlers, &remaining); 34847e4937aSGao Xiang if (ret != -ENOATTR) 34947e4937aSGao Xiang break; 35047e4937aSGao Xiang } 35147e4937aSGao Xiang return ret ? ret : it->buffer_size; 35247e4937aSGao Xiang } 35347e4937aSGao Xiang 354*8e823961SJingbo Xu static int shared_getxattr(struct inode *inode, struct erofs_xattr_iter *it) 35547e4937aSGao Xiang { 356a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 357*8e823961SJingbo Xu struct super_block *const sb = it->sb; 358eba67eb6SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(sb); 359eba67eb6SJingbo Xu unsigned int i; 36047e4937aSGao Xiang int ret = -ENOATTR; 36147e4937aSGao Xiang 36247e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 363*8e823961SJingbo Xu it->pos = erofs_pos(sb, sbi->xattr_blkaddr) + 364eba67eb6SJingbo Xu vi->xattr_shared_xattrs[i] * sizeof(__le32); 365*8e823961SJingbo Xu it->kaddr = erofs_bread(&it->buf, erofs_blknr(sb, it->pos), 366*8e823961SJingbo Xu EROFS_KMAP); 367*8e823961SJingbo Xu if (IS_ERR(it->kaddr)) 368*8e823961SJingbo Xu return PTR_ERR(it->kaddr); 36947e4937aSGao Xiang 370*8e823961SJingbo Xu ret = xattr_foreach(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; 392*8e823961SJingbo Xu struct erofs_xattr_iter it; 39347e4937aSGao Xiang 3948d8a09b0SGao Xiang if (!name) 39547e4937aSGao Xiang return -EINVAL; 39647e4937aSGao Xiang 3976020ffe7SJingbo Xu ret = erofs_init_inode_xattrs(inode); 39847e4937aSGao Xiang if (ret) 39947e4937aSGao Xiang return ret; 40047e4937aSGao Xiang 40147e4937aSGao Xiang it.index = index; 402*8e823961SJingbo Xu it.name = (struct qstr)QSTR_INIT(name, strlen(name)); 40347e4937aSGao Xiang if (it.name.len > EROFS_NAME_LEN) 40447e4937aSGao Xiang return -ERANGE; 405bb88e8daSGao Xiang 406*8e823961SJingbo Xu it.sb = inode->i_sb; 407*8e823961SJingbo Xu it.buf = __EROFS_BUF_INITIALIZER; 408*8e823961SJingbo Xu erofs_init_metabuf(&it.buf, it.sb); 40947e4937aSGao Xiang it.buffer = buffer; 41047e4937aSGao Xiang it.buffer_size = buffer_size; 411*8e823961SJingbo Xu it.buffer_ofs = 0; 41247e4937aSGao Xiang 41347e4937aSGao Xiang ret = inline_getxattr(inode, &it); 41447e4937aSGao Xiang if (ret == -ENOATTR) 41547e4937aSGao Xiang ret = shared_getxattr(inode, &it); 416*8e823961SJingbo Xu erofs_put_metabuf(&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 { 424b05f30bcSJingbo Xu if (handler->flags == EROFS_XATTR_INDEX_USER && 425b05f30bcSJingbo Xu !test_opt(&EROFS_I_SB(inode)->opt, XATTR_USER)) 42647e4937aSGao Xiang return -EOPNOTSUPP; 42747e4937aSGao Xiang 42847e4937aSGao Xiang return erofs_getxattr(inode, handler->flags, name, buffer, size); 42947e4937aSGao Xiang } 43047e4937aSGao Xiang 43147e4937aSGao Xiang const struct xattr_handler erofs_xattr_user_handler = { 43247e4937aSGao Xiang .prefix = XATTR_USER_PREFIX, 43347e4937aSGao Xiang .flags = EROFS_XATTR_INDEX_USER, 43447e4937aSGao Xiang .list = erofs_xattr_user_list, 43547e4937aSGao Xiang .get = erofs_xattr_generic_get, 43647e4937aSGao Xiang }; 43747e4937aSGao Xiang 43847e4937aSGao Xiang const struct xattr_handler erofs_xattr_trusted_handler = { 43947e4937aSGao Xiang .prefix = XATTR_TRUSTED_PREFIX, 44047e4937aSGao Xiang .flags = EROFS_XATTR_INDEX_TRUSTED, 44147e4937aSGao Xiang .list = erofs_xattr_trusted_list, 44247e4937aSGao Xiang .get = erofs_xattr_generic_get, 44347e4937aSGao Xiang }; 44447e4937aSGao Xiang 44547e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_SECURITY 44647e4937aSGao Xiang const struct xattr_handler __maybe_unused erofs_xattr_security_handler = { 44747e4937aSGao Xiang .prefix = XATTR_SECURITY_PREFIX, 44847e4937aSGao Xiang .flags = EROFS_XATTR_INDEX_SECURITY, 44947e4937aSGao Xiang .get = erofs_xattr_generic_get, 45047e4937aSGao Xiang }; 45147e4937aSGao Xiang #endif 45247e4937aSGao Xiang 45347e4937aSGao Xiang const struct xattr_handler *erofs_xattr_handlers[] = { 45447e4937aSGao Xiang &erofs_xattr_user_handler, 45547e4937aSGao Xiang &erofs_xattr_trusted_handler, 45647e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_SECURITY 45747e4937aSGao Xiang &erofs_xattr_security_handler, 45847e4937aSGao Xiang #endif 45947e4937aSGao Xiang NULL, 46047e4937aSGao Xiang }; 46147e4937aSGao Xiang 462*8e823961SJingbo Xu static int xattr_entrylist(struct erofs_xattr_iter *it, 46347e4937aSGao Xiang struct erofs_xattr_entry *entry) 46447e4937aSGao Xiang { 46582bc1ef4SJingbo Xu unsigned int base_index = entry->e_name_index; 46682bc1ef4SJingbo Xu unsigned int prefix_len, infix_len = 0; 46782bc1ef4SJingbo Xu const char *prefix, *infix = NULL; 46847e4937aSGao Xiang 46982bc1ef4SJingbo Xu if (entry->e_name_index & EROFS_XATTR_LONG_PREFIX) { 470*8e823961SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(it->sb); 47182bc1ef4SJingbo Xu struct erofs_xattr_prefix_item *pf = sbi->xattr_prefixes + 47282bc1ef4SJingbo Xu (entry->e_name_index & EROFS_XATTR_LONG_PREFIX_MASK); 47347e4937aSGao Xiang 47482bc1ef4SJingbo Xu if (pf >= sbi->xattr_prefixes + sbi->xattr_prefix_count) 47582bc1ef4SJingbo Xu return 1; 47682bc1ef4SJingbo Xu infix = pf->prefix->infix; 47782bc1ef4SJingbo Xu infix_len = pf->infix_len; 47882bc1ef4SJingbo Xu base_index = pf->prefix->base_index; 47982bc1ef4SJingbo Xu } 48082bc1ef4SJingbo Xu 48161d325dcSLinus Torvalds prefix = erofs_xattr_prefix(base_index, it->dentry); 482a5488f29SChristian Brauner if (!prefix) 48347e4937aSGao Xiang return 1; 48447e4937aSGao Xiang prefix_len = strlen(prefix); 48547e4937aSGao Xiang 48647e4937aSGao Xiang if (!it->buffer) { 48782bc1ef4SJingbo Xu it->buffer_ofs += prefix_len + infix_len + 48882bc1ef4SJingbo Xu entry->e_name_len + 1; 48947e4937aSGao Xiang return 1; 49047e4937aSGao Xiang } 49147e4937aSGao Xiang 49282bc1ef4SJingbo Xu if (it->buffer_ofs + prefix_len + infix_len + 49347e4937aSGao Xiang + entry->e_name_len + 1 > it->buffer_size) 49447e4937aSGao Xiang return -ERANGE; 49547e4937aSGao Xiang 49647e4937aSGao Xiang memcpy(it->buffer + it->buffer_ofs, prefix, prefix_len); 49782bc1ef4SJingbo Xu memcpy(it->buffer + it->buffer_ofs + prefix_len, infix, infix_len); 49882bc1ef4SJingbo Xu it->buffer_ofs += prefix_len + infix_len; 49947e4937aSGao Xiang return 0; 50047e4937aSGao Xiang } 50147e4937aSGao Xiang 502*8e823961SJingbo Xu static int xattr_namelist(struct erofs_xattr_iter *it, 50347e4937aSGao Xiang unsigned int processed, char *buf, unsigned int len) 50447e4937aSGao Xiang { 50547e4937aSGao Xiang memcpy(it->buffer + it->buffer_ofs, buf, len); 50647e4937aSGao Xiang it->buffer_ofs += len; 50747e4937aSGao Xiang return 0; 50847e4937aSGao Xiang } 50947e4937aSGao Xiang 510*8e823961SJingbo Xu static int xattr_skipvalue(struct erofs_xattr_iter *it, 51147e4937aSGao Xiang unsigned int value_sz) 51247e4937aSGao Xiang { 51347e4937aSGao Xiang it->buffer[it->buffer_ofs++] = '\0'; 51447e4937aSGao Xiang return 1; 51547e4937aSGao Xiang } 51647e4937aSGao Xiang 51747e4937aSGao Xiang static const struct xattr_iter_handlers list_xattr_handlers = { 51847e4937aSGao Xiang .entry = xattr_entrylist, 51947e4937aSGao Xiang .name = xattr_namelist, 52047e4937aSGao Xiang .alloc_buffer = xattr_skipvalue, 52147e4937aSGao Xiang .value = NULL 52247e4937aSGao Xiang }; 52347e4937aSGao Xiang 524*8e823961SJingbo Xu static int inline_listxattr(struct erofs_xattr_iter *it) 52547e4937aSGao Xiang { 52647e4937aSGao Xiang int ret; 52747e4937aSGao Xiang unsigned int remaining; 52847e4937aSGao Xiang 529*8e823961SJingbo Xu ret = inline_xattr_iter_begin(it, d_inode(it->dentry)); 53047e4937aSGao Xiang if (ret < 0) 53147e4937aSGao Xiang return ret; 53247e4937aSGao Xiang 53347e4937aSGao Xiang remaining = ret; 53447e4937aSGao Xiang while (remaining) { 535*8e823961SJingbo Xu ret = xattr_foreach(it, &list_xattr_handlers, &remaining); 53647e4937aSGao Xiang if (ret) 53747e4937aSGao Xiang break; 53847e4937aSGao Xiang } 53947e4937aSGao Xiang return ret ? ret : it->buffer_ofs; 54047e4937aSGao Xiang } 54147e4937aSGao Xiang 542*8e823961SJingbo Xu static int shared_listxattr(struct erofs_xattr_iter *it) 54347e4937aSGao Xiang { 54447e4937aSGao Xiang struct inode *const inode = d_inode(it->dentry); 545a5876e24SGao Xiang struct erofs_inode *const vi = EROFS_I(inode); 546*8e823961SJingbo Xu struct super_block *const sb = it->sb; 547eba67eb6SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(sb); 548eba67eb6SJingbo Xu unsigned int i; 54947e4937aSGao Xiang int ret = 0; 55047e4937aSGao Xiang 55147e4937aSGao Xiang for (i = 0; i < vi->xattr_shared_count; ++i) { 552*8e823961SJingbo Xu it->pos = erofs_pos(sb, sbi->xattr_blkaddr) + 553eba67eb6SJingbo Xu vi->xattr_shared_xattrs[i] * sizeof(__le32); 554*8e823961SJingbo Xu it->kaddr = erofs_bread(&it->buf, erofs_blknr(sb, it->pos), 555*8e823961SJingbo Xu EROFS_KMAP); 556*8e823961SJingbo Xu if (IS_ERR(it->kaddr)) 557*8e823961SJingbo Xu return PTR_ERR(it->kaddr); 55847e4937aSGao Xiang 559*8e823961SJingbo Xu ret = xattr_foreach(it, &list_xattr_handlers, NULL); 56047e4937aSGao Xiang if (ret) 56147e4937aSGao Xiang break; 56247e4937aSGao Xiang } 56347e4937aSGao Xiang return ret ? ret : it->buffer_ofs; 56447e4937aSGao Xiang } 56547e4937aSGao Xiang 56647e4937aSGao Xiang ssize_t erofs_listxattr(struct dentry *dentry, 56747e4937aSGao Xiang char *buffer, size_t buffer_size) 56847e4937aSGao Xiang { 56947e4937aSGao Xiang int ret; 570*8e823961SJingbo Xu struct erofs_xattr_iter it; 57147e4937aSGao Xiang 5726020ffe7SJingbo Xu ret = erofs_init_inode_xattrs(d_inode(dentry)); 573926d1650SGao Xiang if (ret == -ENOATTR) 574926d1650SGao Xiang return 0; 57547e4937aSGao Xiang if (ret) 57647e4937aSGao Xiang return ret; 57747e4937aSGao Xiang 578*8e823961SJingbo Xu it.sb = dentry->d_sb; 579*8e823961SJingbo Xu it.buf = __EROFS_BUF_INITIALIZER; 580*8e823961SJingbo Xu erofs_init_metabuf(&it.buf, it.sb); 58147e4937aSGao Xiang it.dentry = dentry; 58247e4937aSGao Xiang it.buffer = buffer; 58347e4937aSGao Xiang it.buffer_size = buffer_size; 58447e4937aSGao Xiang it.buffer_ofs = 0; 58547e4937aSGao Xiang 58647e4937aSGao Xiang ret = inline_listxattr(&it); 587bb88e8daSGao Xiang if (ret >= 0 || ret == -ENOATTR) 588bb88e8daSGao Xiang ret = shared_listxattr(&it); 589*8e823961SJingbo Xu erofs_put_metabuf(&it.buf); 59047e4937aSGao Xiang return ret; 59147e4937aSGao Xiang } 59247e4937aSGao Xiang 5939e382914SJingbo Xu void erofs_xattr_prefixes_cleanup(struct super_block *sb) 5949e382914SJingbo Xu { 5959e382914SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(sb); 5969e382914SJingbo Xu int i; 5979e382914SJingbo Xu 5989e382914SJingbo Xu if (sbi->xattr_prefixes) { 5999e382914SJingbo Xu for (i = 0; i < sbi->xattr_prefix_count; i++) 6009e382914SJingbo Xu kfree(sbi->xattr_prefixes[i].prefix); 6019e382914SJingbo Xu kfree(sbi->xattr_prefixes); 6029e382914SJingbo Xu sbi->xattr_prefixes = NULL; 6039e382914SJingbo Xu } 6049e382914SJingbo Xu } 6059e382914SJingbo Xu 6069e382914SJingbo Xu int erofs_xattr_prefixes_init(struct super_block *sb) 6079e382914SJingbo Xu { 6089e382914SJingbo Xu struct erofs_sb_info *sbi = EROFS_SB(sb); 6099e382914SJingbo Xu struct erofs_buf buf = __EROFS_BUF_INITIALIZER; 6109e382914SJingbo Xu erofs_off_t pos = (erofs_off_t)sbi->xattr_prefix_start << 2; 6119e382914SJingbo Xu struct erofs_xattr_prefix_item *pfs; 6129e382914SJingbo Xu int ret = 0, i, len; 6139e382914SJingbo Xu 6149e382914SJingbo Xu if (!sbi->xattr_prefix_count) 6159e382914SJingbo Xu return 0; 6169e382914SJingbo Xu 6179e382914SJingbo Xu pfs = kzalloc(sbi->xattr_prefix_count * sizeof(*pfs), GFP_KERNEL); 6189e382914SJingbo Xu if (!pfs) 6199e382914SJingbo Xu return -ENOMEM; 6209e382914SJingbo Xu 6210a17567bSJingbo Xu if (sbi->packed_inode) 6229e382914SJingbo Xu buf.inode = sbi->packed_inode; 6239e382914SJingbo Xu else 6249e382914SJingbo Xu erofs_init_metabuf(&buf, sb); 6259e382914SJingbo Xu 6269e382914SJingbo Xu for (i = 0; i < sbi->xattr_prefix_count; i++) { 6279e382914SJingbo Xu void *ptr = erofs_read_metadata(sb, &buf, &pos, &len); 6289e382914SJingbo Xu 6299e382914SJingbo Xu if (IS_ERR(ptr)) { 6309e382914SJingbo Xu ret = PTR_ERR(ptr); 6319e382914SJingbo Xu break; 6329e382914SJingbo Xu } else if (len < sizeof(*pfs->prefix) || 6339e382914SJingbo Xu len > EROFS_NAME_LEN + sizeof(*pfs->prefix)) { 6349e382914SJingbo Xu kfree(ptr); 6359e382914SJingbo Xu ret = -EFSCORRUPTED; 6369e382914SJingbo Xu break; 6379e382914SJingbo Xu } 6389e382914SJingbo Xu pfs[i].prefix = ptr; 6399e382914SJingbo Xu pfs[i].infix_len = len - sizeof(struct erofs_xattr_long_prefix); 6409e382914SJingbo Xu } 6419e382914SJingbo Xu 6429e382914SJingbo Xu erofs_put_metabuf(&buf); 6439e382914SJingbo Xu sbi->xattr_prefixes = pfs; 6449e382914SJingbo Xu if (ret) 6459e382914SJingbo Xu erofs_xattr_prefixes_cleanup(sb); 6469e382914SJingbo Xu return ret; 6479e382914SJingbo Xu } 6489e382914SJingbo Xu 64947e4937aSGao Xiang #ifdef CONFIG_EROFS_FS_POSIX_ACL 6500cad6246SMiklos Szeredi struct posix_acl *erofs_get_acl(struct inode *inode, int type, bool rcu) 65147e4937aSGao Xiang { 65247e4937aSGao Xiang struct posix_acl *acl; 65347e4937aSGao Xiang int prefix, rc; 65447e4937aSGao Xiang char *value = NULL; 65547e4937aSGao Xiang 6560cad6246SMiklos Szeredi if (rcu) 6570cad6246SMiklos Szeredi return ERR_PTR(-ECHILD); 6580cad6246SMiklos Szeredi 65947e4937aSGao Xiang switch (type) { 66047e4937aSGao Xiang case ACL_TYPE_ACCESS: 66147e4937aSGao Xiang prefix = EROFS_XATTR_INDEX_POSIX_ACL_ACCESS; 66247e4937aSGao Xiang break; 66347e4937aSGao Xiang case ACL_TYPE_DEFAULT: 66447e4937aSGao Xiang prefix = EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT; 66547e4937aSGao Xiang break; 66647e4937aSGao Xiang default: 66747e4937aSGao Xiang return ERR_PTR(-EINVAL); 66847e4937aSGao Xiang } 66947e4937aSGao Xiang 67047e4937aSGao Xiang rc = erofs_getxattr(inode, prefix, "", NULL, 0); 67147e4937aSGao Xiang if (rc > 0) { 67247e4937aSGao Xiang value = kmalloc(rc, GFP_KERNEL); 67347e4937aSGao Xiang if (!value) 67447e4937aSGao Xiang return ERR_PTR(-ENOMEM); 67547e4937aSGao Xiang rc = erofs_getxattr(inode, prefix, "", value, rc); 67647e4937aSGao Xiang } 67747e4937aSGao Xiang 67847e4937aSGao Xiang if (rc == -ENOATTR) 67947e4937aSGao Xiang acl = NULL; 68047e4937aSGao Xiang else if (rc < 0) 68147e4937aSGao Xiang acl = ERR_PTR(rc); 68247e4937aSGao Xiang else 68347e4937aSGao Xiang acl = posix_acl_from_xattr(&init_user_ns, value, rc); 68447e4937aSGao Xiang kfree(value); 68547e4937aSGao Xiang return acl; 68647e4937aSGao Xiang } 68747e4937aSGao Xiang #endif 688