github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-11-07 06:17:02 +01:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

ocfs2: reject inconsistent local xattr entries

Browse Source 
[BUG]
A corrupt OCFS2 xattr entry can set OCFS2_XATTR_ENTRY_LOCAL while
keeping xe_value_size larger than OCFS2_XATTR_INLINE_SIZE. When that
entry reaches namevalue_size_xe(), the filesystem hits its BUG_ON:

kernel BUG at fs/ocfs2/xattr.c:231!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
RIP: 0010:namevalue_size_xe fs/ocfs2/xattr.c:231 [inline]
RIP: 0010:ocfs2_xa_block_wipe_namevalue+0x2e4/0x330 fs/ocfs2/xattr.c:1638
Call Trace:
 ocfs2_xa_wipe_namevalue fs/ocfs2/xattr.c:1470 [inline]
 ocfs2_xa_remove_entry+0xae/0x1d0 fs/ocfs2/xattr.c:1941
 ocfs2_xa_remove fs/ocfs2/xattr.c:2043 [inline]
 ocfs2_xa_set+0x11a8/0x30a0 fs/ocfs2/xattr.c:2247
 ocfs2_xattr_ibody_set+0x302/0xc50 fs/ocfs2/xattr.c:2795
 __ocfs2_xattr_set_handle+0x7e6/0xdb0 fs/ocfs2/xattr.c:3416
 ocfs2_xattr_set+0x1447/0x2610 fs/ocfs2/xattr.c:3650
 ocfs2_xattr_security_set+0x37/0x50 fs/ocfs2/xattr.c:7241
 __vfs_removexattr+0x14d/0x1d0 fs/xattr.c:518
 cap_inode_killpriv+0x29/0x50 security/commoncap.c:355
 security_inode_killpriv+0x105/0x220 security/security.c:2724
 setattr_prepare+0x147/0x8a0 fs/attr.c:219
 ocfs2_setattr+0x504/0x1fd0 fs/ocfs2/file.c:1148
 notify_change+0x4b5/0x1030 fs/attr.c:546
 do_truncate+0x1d2/0x230 fs/open.c:68
 handle_truncate fs/namei.c:3596 [inline]
 do_open fs/namei.c:3979 [inline]
 path_openat+0x260f/0x2ce0 fs/namei.c:4134
 do_filp_open+0x1f6/0x430 fs/namei.c:4161
 do_sys_openat2+0x117/0x1c0 fs/open.c:1437
 ...

[CAUSE]
namevalue_size_xe() assumes that local entries contain an inline value
no larger than OCFS2_XATTR_INLINE_SIZE. Existing xattr metadata
validation only checks whether the value fits the storage region, and
cached entries can reach lookup and bucket maintenance paths without a
semantic check. A corrupt entry can therefore be passed to
namevalue_size_xe().

[FIX]
Validate the local/value-size invariant in the existing flat and bucket
metadata validators and before accepting matched entries or traversing
bucket entries in paths that call namevalue_size_xe(). Return an OCFS2
corruption error instead of firing the assertion.

Link: https://lore.kernel.org/20260806085012.2650042-1-gality369@gmail.com
Signed-off-by: ZhengYuan Huang <gality369@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
This commit is contained in:
ZhengYuan Huang 2026-08-06 16:50:12 +08:00 committed by Andrew Morton
parent c204bf5ac3
commit 415ad91474
1 changed files with 46 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

53
fs/ocfs2/xattr.c
View File

@ -237,6 +237,21 @@ static int namevalue_size_xe(struct ocfs2_xattr_entry *xe)
return namevalue_size(xe->xe_name_len, value_len);
}
static int ocfs2_validate_xattr_entry(struct super_block *sb, u64 blkno,
struct ocfs2_xattr_entry *xe)
{
u64 value_len = le64_to_cpu(xe->xe_value_size);
if (value_len > OCFS2_XATTR_INLINE_SIZE &&
ocfs2_xattr_is_local(xe))
return ocfs2_error(sb,
"Invalid local xattr in block %llu: value size %llu\n",
(unsigned long long)blkno,
(unsigned long long)value_len);
return 0;
}
static int ocfs2_xattr_bucket_get_name_value(struct super_block *sb,
struct ocfs2_xattr_header *xh,
@ -989,7 +1004,7 @@ static int ocfs2_validate_xattr_entries_flat(struct super_block *sb, u64 blkno,
size_t entries_limit = region_size;
size_t nv_limit = region_size;
size_t max_entries;
int i;
int i, ret;
if (region_size < sizeof(*xh))
return ocfs2_error(sb,
@ -1009,6 +1024,11 @@ static int ocfs2_validate_xattr_entries_flat(struct super_block *sb, u64 blkno,
struct ocfs2_xattr_entry *xe = &xh->xh_entries[i];
size_t name_offset = le16_to_cpu(xe->xe_name_offset);
size_t value_offset;
u64 value_len = le64_to_cpu(xe->xe_value_size);
ret = ocfs2_validate_xattr_entry(sb, blkno, xe);
if (ret)
return ret;
if (name_offset > nv_limit ||
xe->xe_name_len > nv_limit - name_offset)
@ -1023,8 +1043,7 @@ static int ocfs2_validate_xattr_entries_flat(struct super_block *sb, u64 blkno,
(unsigned long long)blkno, i);
if (ocfs2_xattr_is_local(xe)) {
if (le64_to_cpu(xe->xe_value_size) >
nv_limit - value_offset)
if (value_len > nv_limit - value_offset)
return ocfs2_error(sb,
"Invalid xattr in block %llu: entry %d value is out of bounds\n",
(unsigned long long)blkno,
@ -1109,7 +1128,7 @@ static int ocfs2_validate_xattr_bucket(struct ocfs2_xattr_bucket *bucket,
size_t entries_limit = sb->s_blocksize;
size_t nv_limit = sb->s_blocksize;
size_t max_entries;
int i;
int i, ret;
if (region_size < sizeof(*xh))
return ocfs2_error(sb,
@ -1137,6 +1156,11 @@ static int ocfs2_validate_xattr_bucket(struct ocfs2_xattr_bucket *bucket,
size_t block_off = name_offset >> sb->s_blocksize_bits;
size_t block_offset = name_offset % nv_limit;
size_t value_offset;
u64 value_len = le64_to_cpu(xe->xe_value_size);
ret = ocfs2_validate_xattr_entry(sb, blkno, xe);
if (ret)
return ret;
if (name_offset >= region_size || block_off >= bucket->bu_blocks)
return ocfs2_error(sb,
@ -1155,8 +1179,7 @@ static int ocfs2_validate_xattr_bucket(struct ocfs2_xattr_bucket *bucket,
(unsigned long long)blkno, i);
if (ocfs2_xattr_is_local(xe)) {
if (le64_to_cpu(xe->xe_value_size) >
nv_limit - value_offset)
if (value_len > nv_limit - value_offset)
return ocfs2_error(sb,
"Invalid xattr bucket %llu: entry %d value is out of bounds\n",
(unsigned long long)blkno,
@ -1304,7 +1327,7 @@ static int ocfs2_xattr_find_entry(struct inode *inode, int name_index,
{
struct ocfs2_xattr_entry *entry;
size_t name_len;
int i, name_offset, cmp = 1;
int i, name_offset, cmp = 1, ret;
if (name == NULL)
return -EINVAL;
@ -1327,6 +1350,12 @@ static int ocfs2_xattr_find_entry(struct inode *inode, int name_index,
return -EFSCORRUPTED;
}
cmp = memcmp(name, (xs->base + name_offset), name_len);
if (!cmp) {
ret = ocfs2_validate_xattr_entry(inode->i_sb,
OCFS2_I(inode)->ip_blkno, entry);
if (ret)
return ret;
}
}
if (cmp == 0)
break;
@ -4068,6 +4097,10 @@ static int ocfs2_find_xe_in_bucket(struct inode *inode,
xe_name = bucket_block(bucket, block_off) + new_offset;
if (!memcmp(name, xe_name, name_len)) {
ret = ocfs2_validate_xattr_entry(inode->i_sb,
OCFS2_I(inode)->ip_blkno, xe);
if (ret)
break;
*xe_index = i;
*found = 1;
ret = 0;
@ -4705,6 +4738,9 @@ static int ocfs2_defrag_xattr_bucket(struct inode *inode,
xe = xh->xh_entries;
end = OCFS2_XATTR_BUCKET_SIZE;
for (i = 0; i < le16_to_cpu(xh->xh_count); i++, xe++) {
ret = ocfs2_validate_xattr_entry(inode->i_sb, blkno, xe);
if (ret)
goto out;
offset = le16_to_cpu(xe->xe_name_offset);
len = namevalue_size_xe(xe);
@ -4987,6 +5023,9 @@ static int ocfs2_divide_xattr_bucket(struct inode *inode,
name_value_len = 0;
for (i = 0; i < start; i++) {
xe = &xh->xh_entries[i];
ret = ocfs2_validate_xattr_entry(inode->i_sb, blk, xe);
if (ret)
goto out;
name_value_len += namevalue_size_xe(xe);
if (le16_to_cpu(xe->xe_name_offset) < name_offset)
name_offset = le16_to_cpu(xe->xe_name_offset);