From: Theodore Ts'o <tytso@mit.edu>
Date: Fri, 26 Sep 2025 01:11:52 +0000 (-0400)
Subject: e2fsck: check for extended attributes with ea_inode but a zero ea_size
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e4c9d0111e2894c19e46403119de5e4d6e576c12;p=thirdparty%2Fe2fsprogs.git

e2fsck: check for extended attributes with ea_inode but a zero ea_size

The combination of e_value_inum != 0 and e_value_size == 0 is invalid
and can trigger kernel warnings.  This should only happen with
delierately corrupted extended attribute entries; so if we come across
one, just clear the xattrs.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
---

diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
index e7d5d0ae9..fdde76cc2 100644
--- a/e2fsck/pass1.c
+++ b/e2fsck/pass1.c
@@ -343,6 +343,12 @@ static problem_t check_large_ea_inode(e2fsck_t ctx,
 
 	e2fsck_read_inode(ctx, entry->e_value_inum, &inode, "pass1");
 
+	if (entry->e_value_size == 0 ||
+	    entry->e_value_size != EXT2_I_SIZE(&inode)) {
+		pctx->num = entry->e_value_size;
+		return PR_1_ATTR_VALUE_SIZE;
+	}
+
 	retval = ext2fs_ext_attr_hash_entry3(ctx->fs, entry, NULL, &hash,
 					     &signed_hash);
 	if (retval) {
diff --git a/tests/f_ea_inode_self_ref/expect.1 b/tests/f_ea_inode_self_ref/expect.1
index f94c04d96..339df1844 100644
--- a/tests/f_ea_inode_self_ref/expect.1
+++ b/tests/f_ea_inode_self_ref/expect.1
@@ -1,7 +1,7 @@
 Pass 1: Checking inodes, blocks, and sizes
 Inode 16 has INLINE_DATA_FL flag but extended attribute not found.  Truncate? yes
 
-Extended attribute in inode 16 has a hash (553648128) which is invalid
+Extended attribute in inode 16 has a value size (0) which is invalid
 Clear? yes
 
 Pass 2: Checking directory structure
diff --git a/tests/f_ea_zero_size/expect.1 b/tests/f_ea_zero_size/expect.1
new file mode 100644
index 000000000..2aa0ae653
--- /dev/null
+++ b/tests/f_ea_zero_size/expect.1
@@ -0,0 +1,30 @@
+Pass 1: Checking inodes, blocks, and sizes
+Extended attribute in inode 12 has a value size (0) which is invalid
+Clear? yes
+
+Inode 12, i_blocks is 8, should be 0.  Fix? yes
+
+Pass 2: Checking directory structure
+Pass 3: Checking directory connectivity
+Pass 4: Checking reference counts
+Regular filesystem inode 14 has EA_INODE flag set. Clear? yes
+
+Unattached inode 14
+Connect to /lost+found? yes
+
+Inode 14 ref count is 2, should be 1.  Fix? yes
+
+Pass 5: Checking group summary information
+Block bitmap differences:  -13
+Fix? yes
+
+Free blocks count wrong for group #0 (46, counted=47).
+Fix? yes
+
+Free blocks count wrong (46, counted=47).
+Fix? yes
+
+
+test_filesys: ***** FILE SYSTEM WAS MODIFIED *****
+test_filesys: 21/32 files (0.0% non-contiguous), 17/64 blocks
+Exit status is 1
diff --git a/tests/f_ea_zero_size/expect.2 b/tests/f_ea_zero_size/expect.2
new file mode 100644
index 000000000..17211daf9
--- /dev/null
+++ b/tests/f_ea_zero_size/expect.2
@@ -0,0 +1,7 @@
+Pass 1: Checking inodes, blocks, and sizes
+Pass 2: Checking directory structure
+Pass 3: Checking directory connectivity
+Pass 4: Checking reference counts
+Pass 5: Checking group summary information
+test_filesys: 21/32 files (0.0% non-contiguous), 17/64 blocks
+Exit status is 0
diff --git a/tests/f_ea_zero_size/image.gz b/tests/f_ea_zero_size/image.gz
new file mode 100644
index 000000000..fff5b203f
Binary files /dev/null and b/tests/f_ea_zero_size/image.gz differ
diff --git a/tests/f_ea_zero_size/name b/tests/f_ea_zero_size/name
new file mode 100644
index 000000000..95d9893c1
--- /dev/null
+++ b/tests/f_ea_zero_size/name
@@ -0,0 +1 @@
+zero extended attribute size with ea_inode