Skip to content

ensure chunk is not out of bound, which will bring data corruption. #18620

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
tiehexue wants to merge 2 commits into
base: master
Choose a base branch
from
+72 −50
Open

ensure chunk is not out of bound, which will bring data corruption. #18620

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
1c9117f
ensure chunk in zap leaf is not out of bound.
tiehexue Jun 3, 2026
7067de8
avoid increasing the structure size
tiehexue Jun 23, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
1 change: 1 addition & 0 deletions include/sys/zap_leaf.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -165,6 +165,7 @@ typedef struct zap_leaf {
krwlock_t l_rwlock;
uint64_t l_blkid; /* 1<<ZAP_BLOCK_SHIFT byte block off */
uint_t l_bs; /* block size shift */
uint16_t l_chunk_count; /* for bound checking */
Comment thread
tiehexue marked this conversation as resolved.
dmu_buf_t *l_dbuf;
} zap_leaf_t;

Expand Down
5 changes: 3 additions & 2 deletions module/zfs/zap_fat.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -486,6 +486,7 @@ zap_open_leaf(uint64_t blkid, dmu_buf_t *db)
l->l_blkid = blkid;
l->l_bs = highbit64(db->db_size) - 1;
l->l_dbuf = db;
l->l_chunk_count = ZAP_LEAF_NUMCHUNKS(l);

dmu_buf_init_user(&l->l_dbu, zap_leaf_evict_sync, NULL, &l->l_dbuf);
zap_leaf_t *winner = dmu_buf_set_user(db, &l->l_dbu);
Expand All @@ -508,14 +509,14 @@ zap_open_leaf(uint64_t blkid, dmu_buf_t *db)
* There should be more hash entries than there can be
* chunks to put in the hash table
*/
ASSERT3U(ZAP_LEAF_HASH_NUMENTRIES(l), >, ZAP_LEAF_NUMCHUNKS(l) / 3);
ASSERT3U(ZAP_LEAF_HASH_NUMENTRIES(l), >, l->l_chunk_count / 3);

/* The chunks should begin at the end of the hash table */
ASSERT3P(&ZAP_LEAF_CHUNK(l, 0), ==, (zap_leaf_chunk_t *)
&zap_leaf_phys(l)->l_hash[ZAP_LEAF_HASH_NUMENTRIES(l)]);

/* The chunks should end at the end of the block */
ASSERT3U((uintptr_t)&ZAP_LEAF_CHUNK(l, ZAP_LEAF_NUMCHUNKS(l)) -
ASSERT3U((uintptr_t)&ZAP_LEAF_CHUNK(l, l->l_chunk_count) -
(uintptr_t)zap_leaf_phys(l), ==, l->l_dbuf->db_size);

return (l);
Expand Down
116 changes: 68 additions & 48 deletions module/zfs/zap_leaf.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -102,6 +102,7 @@ zap_leaf_byteswap(zap_leaf_phys_t *buf, size_t size)
l_dbuf.db_data = buf;
l.l_bs = highbit64(size) - 1;
l.l_dbuf = &l_dbuf;
l.l_chunk_count = ZAP_LEAF_NUMCHUNKS(&l);

buf->l_hdr.lh_block_type = BSWAP_64(buf->l_hdr.lh_block_type);
buf->l_hdr.lh_prefix = BSWAP_64(buf->l_hdr.lh_prefix);
Expand All @@ -114,7 +115,7 @@ zap_leaf_byteswap(zap_leaf_phys_t *buf, size_t size)
for (uint_t i = 0; i < ZAP_LEAF_HASH_NUMENTRIES(&l); i++)
buf->l_hash[i] = BSWAP_16(buf->l_hash[i]);

for (uint_t i = 0; i < ZAP_LEAF_NUMCHUNKS(&l); i++) {
for (uint_t i = 0; i < l.l_chunk_count; i++) {
zap_leaf_chunk_t *lc = &ZAP_LEAF_CHUNK(&l, i);
struct zap_leaf_entry *le;

Expand Down Expand Up @@ -152,18 +153,19 @@ void
zap_leaf_init(zap_leaf_t *l, boolean_t sort)
{
l->l_bs = highbit64(l->l_dbuf->db_size) - 1;
l->l_chunk_count = ZAP_LEAF_NUMCHUNKS(l);
memset(&zap_leaf_phys(l)->l_hdr, 0,
sizeof (struct zap_leaf_header));
memset(zap_leaf_phys(l)->l_hash, CHAIN_END,
2*ZAP_LEAF_HASH_NUMENTRIES(l));
for (uint_t i = 0; i < ZAP_LEAF_NUMCHUNKS(l); i++) {
for (uint_t i = 0; i < l->l_chunk_count; i++) {
ZAP_LEAF_CHUNK(l, i).l_free.lf_type = ZAP_CHUNK_FREE;
ZAP_LEAF_CHUNK(l, i).l_free.lf_next = i+1;
}
ZAP_LEAF_CHUNK(l, ZAP_LEAF_NUMCHUNKS(l)-1).l_free.lf_next = CHAIN_END;
ZAP_LEAF_CHUNK(l, l->l_chunk_count-1).l_free.lf_next = CHAIN_END;
zap_leaf_phys(l)->l_hdr.lh_block_type = ZBT_LEAF;
zap_leaf_phys(l)->l_hdr.lh_magic = ZAP_LEAF_MAGIC;
zap_leaf_phys(l)->l_hdr.lh_nfree = ZAP_LEAF_NUMCHUNKS(l);
zap_leaf_phys(l)->l_hdr.lh_nfree = l->l_chunk_count;
if (sort)
zap_leaf_phys(l)->l_hdr.lh_flags |= ZLF_ENTRIES_CDSORTED;
}
Expand All @@ -178,7 +180,7 @@ zap_leaf_chunk_alloc(zap_leaf_t *l)
ASSERT(zap_leaf_phys(l)->l_hdr.lh_nfree > 0);

uint_t chunk = zap_leaf_phys(l)->l_hdr.lh_freelist;
ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
ASSERT3U(chunk, <, l->l_chunk_count);
ASSERT3U(ZAP_LEAF_CHUNK(l, chunk).l_free.lf_type, ==, ZAP_CHUNK_FREE);

zap_leaf_phys(l)->l_hdr.lh_freelist =
Expand All @@ -193,16 +195,24 @@ static void
zap_leaf_chunk_free(zap_leaf_t *l, uint16_t chunk)
{
struct zap_leaf_free *zlf = &ZAP_LEAF_CHUNK(l, chunk).l_free;
ASSERT3U(zap_leaf_phys(l)->l_hdr.lh_nfree, <, ZAP_LEAF_NUMCHUNKS(l));
ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
ASSERT(zlf->lf_type != ZAP_CHUNK_FREE);
ASSERT3U(zap_leaf_phys(l)->l_hdr.lh_nfree, <, l->l_chunk_count);

// if chunk is out of bounds, it means the caller is trying
// to free a chunk that should never allocated, so we just ignore it.
if (chunk < l->l_chunk_count) {
ASSERT(zlf->lf_type != ZAP_CHUNK_FREE);

zlf->lf_type = ZAP_CHUNK_FREE;
zlf->lf_next = zap_leaf_phys(l)->l_hdr.lh_freelist;
memset(zlf->lf_pad, 0, sizeof (zlf->lf_pad)); /* help it to compress */
zap_leaf_phys(l)->l_hdr.lh_freelist = chunk;
zlf->lf_type = ZAP_CHUNK_FREE;
zlf->lf_next = zap_leaf_phys(l)->l_hdr.lh_freelist;
memset(zlf->lf_pad, 0,
sizeof (zlf->lf_pad)); /* help it to compress */
zap_leaf_phys(l)->l_hdr.lh_freelist = chunk;

zap_leaf_phys(l)->l_hdr.lh_nfree++;
zap_leaf_phys(l)->l_hdr.lh_nfree++;
} else {
zfs_dbgmsg("zap_leaf_chunk_free: chunk %u out of bounds"
" ignored", chunk);
}
}

/*
Expand Down Expand Up @@ -258,8 +268,7 @@ zap_leaf_array_copy(zap_leaf_t *l, uint16_t chunk, zap_leaf_t *nl)
uint16_t new_chunk;
uint16_t *nchunkp = &new_chunk;

while (chunk != CHAIN_END) {
ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
while (chunk < l->l_chunk_count) {
uint16_t nchunk = zap_leaf_chunk_alloc(nl);

struct zap_leaf_array *la =
Expand Down Expand Up @@ -289,8 +298,7 @@ zap_leaf_array_free(zap_leaf_t *l, uint16_t chunk)
uint16_t *tailp = &hdr->lh_freelist;
uint16_t oldfree = *tailp;

while (chunk != CHAIN_END) {
ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
while (chunk < l->l_chunk_count) {
zap_leaf_chunk_t *c = &ZAP_LEAF_CHUNK(l, chunk);
ASSERT3U(c->l_array.la_type, ==, ZAP_CHUNK_ARRAY);

Expand All @@ -301,7 +309,7 @@ zap_leaf_array_free(zap_leaf_t *l, uint16_t chunk)
memset(c->l_free.lf_pad, 0, sizeof (c->l_free.lf_pad));
tailp = &c->l_free.lf_next;

ASSERT3U(hdr->lh_nfree, <, ZAP_LEAF_NUMCHUNKS(l));
ASSERT3U(hdr->lh_nfree, <, l->l_chunk_count);
hdr->lh_nfree++;
}

Expand All @@ -322,7 +330,8 @@ zap_leaf_array_read(zap_leaf_t *l, uint16_t chunk,
ASSERT3U(array_int_len, <=, buf_int_len);

/* Fast path for one 8-byte integer */
if (array_int_len == 8 && buf_int_len == 8 && len == 1) {
if (array_int_len == 8 && buf_int_len == 8 &&
len == 1 && chunk < l->l_chunk_count) {
struct zap_leaf_array *la = &ZAP_LEAF_CHUNK(l, chunk).l_array;
uint8_t *ip = la->la_array;
uint64_t *buf64 = buf;
Expand All @@ -337,7 +346,7 @@ zap_leaf_array_read(zap_leaf_t *l, uint16_t chunk,
/* Fast path for an array of 1-byte integers (eg. the entry name) */
if (array_int_len == 1 && buf_int_len == 1 &&
buf_len > array_len + ZAP_LEAF_ARRAY_BYTES) {
while (chunk != CHAIN_END) {
while (chunk < l->l_chunk_count) {
struct zap_leaf_array *la =
&ZAP_LEAF_CHUNK(l, chunk).l_array;
memcpy(p, la->la_array, ZAP_LEAF_ARRAY_BYTES);
Expand All @@ -350,20 +359,27 @@ zap_leaf_array_read(zap_leaf_t *l, uint16_t chunk,
while (len > 0) {
struct zap_leaf_array *la = &ZAP_LEAF_CHUNK(l, chunk).l_array;

ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
for (int i = 0; i < ZAP_LEAF_ARRAY_BYTES; i++) {
value = (value << 8) | la->la_array[i];
byten++;
if (byten == array_int_len) {
stv(buf_int_len, p, value);
byten = 0;
len--;
if (len == 0)
return;
p += buf_int_len;
// If chunk is out of bounds, it means the leaf is corrupted,
// so we just stop here.
if (chunk < l->l_chunk_count) {
for (int i = 0; i < ZAP_LEAF_ARRAY_BYTES; i++) {
value = (value << 8) | la->la_array[i];
byten++;
if (byten == array_int_len) {
stv(buf_int_len, p, value);
byten = 0;
len--;
if (len == 0)
return;
p += buf_int_len;
}
}
chunk = la->la_next;
} else {
zfs_dbgmsg("zap_leaf_array_read: chunk %u "
"out of bounds.", chunk);
break;
}
chunk = la->la_next;
}
}

Expand Down Expand Up @@ -407,12 +423,18 @@ zap_leaf_array_match(zap_leaf_t *l, zap_name_t *zn,
while (bseen < array_numints) {
struct zap_leaf_array *la = &ZAP_LEAF_CHUNK(l, chunk).l_array;
int toread = MIN(array_numints - bseen, ZAP_LEAF_ARRAY_BYTES);
ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
if (memcmp(la->la_array, (char *)zn->zn_key_orig + bseen,
toread))
if (chunk < l->l_chunk_count) {
if (memcmp(la->la_array,
(char *)zn->zn_key_orig + bseen,
toread))
break;
chunk = la->la_next;
bseen += toread;
} else {
zfs_dbgmsg("zap_leaf_array_match: chunk %u "
"out of bounds", chunk);
break;
chunk = la->la_next;
bseen += toread;
}
}
return (bseen == array_numints);
}
Expand All @@ -429,11 +451,9 @@ zap_leaf_lookup(zap_leaf_t *l, zap_name_t *zn, zap_entry_handle_t *zeh)
ASSERT3U(zap_leaf_phys(l)->l_hdr.lh_magic, ==, ZAP_LEAF_MAGIC);

for (uint16_t *chunkp = LEAF_HASH_ENTPTR(l, zn->zn_hash);
*chunkp != CHAIN_END; chunkp = &le->le_next) {
*chunkp < l->l_chunk_count; chunkp = &le->le_next) {
uint16_t chunk = *chunkp;
le = ZAP_LEAF_ENTRY(l, chunk);

ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
ASSERT3U(le->le_type, ==, ZAP_CHUNK_ENTRY);

if (le->le_hash != zn->zn_hash)
Expand Down Expand Up @@ -478,10 +498,9 @@ zap_leaf_lookup_closest(zap_leaf_t *l,

for (uint16_t lh = LEAF_HASH(l, h); lh <= bestlh; lh++) {
for (uint16_t chunk = zap_leaf_phys(l)->l_hash[lh];
chunk != CHAIN_END; chunk = le->le_next) {
chunk < l->l_chunk_count; chunk = le->le_next) {
le = ZAP_LEAF_ENTRY(l, chunk);

ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
ASSERT3U(le->le_type, ==, ZAP_CHUNK_ENTRY);

if (HCD_GTEQ(le->le_hash, le->le_cd, h, cd) &&
Expand Down Expand Up @@ -610,7 +629,7 @@ zap_entry_create(zap_leaf_t *l, zap_name_t *zn, uint32_t cd,
cd = 0;

for (chunk = *LEAF_HASH_ENTPTR(l, h);
chunk != CHAIN_END; chunk = le->le_next) {
chunk < l->l_chunk_count; chunk = le->le_next) {
le = ZAP_LEAF_ENTRY(l, chunk);
if (le->le_cd > cd)
break;
Expand All @@ -623,15 +642,16 @@ zap_entry_create(zap_leaf_t *l, zap_name_t *zn, uint32_t cd,
/* old unsorted format; do it the O(n^2) way */
for (cd = 0; ; cd++) {
for (chunk = *LEAF_HASH_ENTPTR(l, h);
chunk != CHAIN_END; chunk = le->le_next) {
chunk < l->l_chunk_count;
chunk = le->le_next) {
le = ZAP_LEAF_ENTRY(l, chunk);
if (le->le_hash == h &&
le->le_cd == cd) {
break;
}
}
/* If this cd is not in use, we are good. */
if (chunk == CHAIN_END)
if (chunk >= l->l_chunk_count)
break;
}
}
Expand Down Expand Up @@ -696,7 +716,7 @@ zap_entry_normalization_conflict(zap_entry_handle_t *zeh, zap_name_t *zn,
return (B_FALSE);

for (uint16_t chunk = *LEAF_HASH_ENTPTR(zeh->zeh_leaf, zeh->zeh_hash);
chunk != CHAIN_END; chunk = le->le_next) {
chunk < zeh->zeh_leaf->l_chunk_count; chunk = le->le_next) {
le = ZAP_LEAF_ENTRY(zeh->zeh_leaf, chunk);
if (le->le_hash != zeh->zeh_hash)
continue;
Expand Down Expand Up @@ -735,7 +755,7 @@ zap_leaf_rehash_entry(zap_leaf_t *l, struct zap_leaf_entry *le, uint16_t entry)
* it is unnecessary there.
*/
for (chunkp = LEAF_HASH_ENTPTR(l, le->le_hash);
*chunkp != CHAIN_END; chunkp = &le2->le_next) {
*chunkp < l->l_chunk_count; chunkp = &le2->le_next) {
le2 = ZAP_LEAF_ENTRY(l, *chunkp);
if (le2->le_cd > le->le_cd)
break;
Expand Down Expand Up @@ -837,7 +857,7 @@ zap_leaf_stats(zap_t *zap, zap_leaf_t *l, zap_stats_t *zs)
uint_t nentries = 0;
uint_t chunk = zap_leaf_phys(l)->l_hash[i];

while (chunk != CHAIN_END) {
while (chunk < l->l_chunk_count) {
struct zap_leaf_entry *le =
ZAP_LEAF_ENTRY(l, chunk);

Expand Down
Loading