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Date: Sat, 13 Feb 2016 14:38:24 -0800
From: "Darrick J. Wong" <darrick.wong@...cle.com>
To: tytso@....edu, darrick.wong@...cle.com
Cc: linux-ext4@...r.kernel.org, Darren Hart <dvhart@...ux.intel.com>,
Richard Purdie <richard.purdie@...uxfoundation.org>
Subject: [PATCH 9/9] libext2fs: sort keys for xattr blocks
Richard Purdie reports that libext2fs doesn't sort attribute keys in
the xattr block correctly, causing the kernel to return -ENODATA when
querying attributes that should be there. Therefore, sort attributes
so that whatever ends up in the xattr block is sorted according to
what the kernel expects.
Cc: Darren Hart <dvhart@...ux.intel.com>
Reported-by: Richard Purdie <richard.purdie@...uxfoundation.org>
Signed-off-by: Darrick J. Wong <darrick.wong@...cle.com>
---
lib/ext2fs/ext_attr.c | 24 +++++++++++-
tests/d_xattr_sorting/expect | 29 ++++++++++++++
tests/d_xattr_sorting/name | 1
tests/d_xattr_sorting/script | 86 ++++++++++++++++++++++++++++++++++++++++++
4 files changed, 139 insertions(+), 1 deletion(-)
create mode 100644 tests/d_xattr_sorting/expect
create mode 100644 tests/d_xattr_sorting/name
create mode 100644 tests/d_xattr_sorting/script
diff --git a/lib/ext2fs/ext_attr.c b/lib/ext2fs/ext_attr.c
index 0a4f8c0..b121837 100644
--- a/lib/ext2fs/ext_attr.c
+++ b/lib/ext2fs/ext_attr.c
@@ -254,10 +254,15 @@ static struct ea_name_index ea_names[] = {
{0, NULL},
};
+static int find_ea_index(char *fullname, char **name, int *index);
+
/* Push empty attributes to the end and inlinedata to the front. */
static int attr_compare(const void *a, const void *b)
{
const struct ext2_xattr *xa = a, *xb = b;
+ char *xa_suffix, *xb_suffix;
+ int xa_idx, xb_idx;
+ int cmp;
if (xa->name == NULL)
return +1;
@@ -267,7 +272,24 @@ static int attr_compare(const void *a, const void *b)
return -1;
else if (!strcmp(xb->name, "system.data"))
return +1;
- return 0;
+
+ /*
+ * Duplicate the kernel's sorting algorithm because xattr blocks
+ * require sorted keys.
+ */
+ xa_suffix = xa->name;
+ xb_suffix = xb->name;
+ xa_idx = xb_idx = 0;
+ find_ea_index(xa->name, &xa_suffix, &xa_idx);
+ find_ea_index(xb->name, &xb_suffix, &xb_idx);
+ cmp = xa_idx - xb_idx;
+ if (cmp)
+ return cmp;
+ cmp = strlen(xa_suffix) - strlen(xb_suffix);
+ if (cmp)
+ return cmp;
+ cmp = strcmp(xa_suffix, xb_suffix);
+ return cmp;
}
static const char *find_ea_prefix(int index)
diff --git a/tests/d_xattr_sorting/expect b/tests/d_xattr_sorting/expect
new file mode 100644
index 0000000..17da663
--- /dev/null
+++ b/tests/d_xattr_sorting/expect
@@ -0,0 +1,29 @@
+debugfs sort extended attributes
+mke2fs -Fq -b 1024 test.img 512
+Exit status is 0
+ea_set / security.SMEG64 -f /tmp/b
+Exit status is 0
+ea_set / security.imb -f /tmp/b
+Exit status is 0
+ea_set / user.moo cow
+Exit status is 0
+ea_list /
+Extended attributes:
+ user.moo = "cow" (3)
+ security.imb = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" (256)
+ security.SMEG64 = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" (256)
+Exit status is 0
+ea_get / security.imb
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+Exit status is 0
+ea_get / nosuchea
+ea_get: Extended attribute key not found while getting extended attribute
+Exit status is 0
+e2fsck -yf -N test_filesys
+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: 11/64 files (0.0% non-contiguous), 29/512 blocks
+Exit status is 0
diff --git a/tests/d_xattr_sorting/name b/tests/d_xattr_sorting/name
new file mode 100644
index 0000000..dde8926
--- /dev/null
+++ b/tests/d_xattr_sorting/name
@@ -0,0 +1 @@
+sort extended attributes in debugfs
diff --git a/tests/d_xattr_sorting/script b/tests/d_xattr_sorting/script
new file mode 100644
index 0000000..30c189a
--- /dev/null
+++ b/tests/d_xattr_sorting/script
@@ -0,0 +1,86 @@
+if test -x $DEBUGFS_EXE; then
+
+OUT=$test_name.log
+EXP=$test_dir/expect
+VERIFY_FSCK_OPT=-yf
+
+TEST_DATA=$test_name.tmp
+VERIFY_DATA=$test_name.ver.tmp
+
+echo "debugfs sort extended attributes" > $OUT
+
+dd if=/dev/zero of=$TMPFILE bs=1k count=512 > /dev/null 2>&1
+
+echo "mke2fs -Fq -b 1024 test.img 512" >> $OUT
+
+$MKE2FS -Fq $TMPFILE 512 > /dev/null 2>&1
+status=$?
+echo Exit status is $status >> $OUT
+
+perl -e 'print "x" x 256;' > /tmp/b
+
+echo "ea_set / security.SMEG64 -f /tmp/b" > $OUT.new
+$DEBUGFS -w -R "ea_set / security.SMEG64 -f /tmp/b" $TMPFILE >> $OUT.new 2>&1
+status=$?
+echo Exit status is $status >> $OUT.new
+sed -f $cmd_dir/filter.sed $OUT.new >> $OUT
+
+echo "ea_set / security.imb -f /tmp/b" > $OUT.new
+$DEBUGFS -w -R "ea_set / security.imb -f /tmp/b" $TMPFILE >> $OUT.new 2>&1
+status=$?
+echo Exit status is $status >> $OUT.new
+sed -f $cmd_dir/filter.sed $OUT.new >> $OUT
+
+echo "ea_set / user.moo cow" > $OUT.new
+$DEBUGFS -w -R "ea_set / user.moo cow" $TMPFILE >> $OUT.new 2>&1
+status=$?
+echo Exit status is $status >> $OUT.new
+sed -f $cmd_dir/filter.sed $OUT.new >> $OUT
+
+rm -rf /tmp/b
+
+echo "ea_list /" > $OUT.new
+$DEBUGFS -w -R "ea_list /" $TMPFILE >> $OUT.new 2>&1
+status=$?
+echo Exit status is $status >> $OUT.new
+sed -f $cmd_dir/filter.sed $OUT.new >> $OUT
+
+echo "ea_get / security.imb" > $OUT.new
+$DEBUGFS -w -R "ea_get / security.imb" $TMPFILE >> $OUT.new 2>&1
+status=$?
+echo Exit status is $status >> $OUT.new
+sed -f $cmd_dir/filter.sed $OUT.new >> $OUT
+
+echo "ea_get / nosuchea" > $OUT.new
+$DEBUGFS -w -R "ea_get / nosuchea" $TMPFILE >> $OUT.new 2>&1
+status=$?
+echo Exit status is $status >> $OUT.new
+sed -f $cmd_dir/filter.sed $OUT.new >> $OUT
+
+echo e2fsck $VERIFY_FSCK_OPT -N test_filesys > $OUT.new
+$FSCK $VERIFY_FSCK_OPT -N test_filesys $TMPFILE >> $OUT.new 2>&1
+status=$?
+echo Exit status is $status >> $OUT.new
+sed -f $cmd_dir/filter.sed $OUT.new >> $OUT
+
+#
+# Do the verification
+#
+
+rm -f $TMPFILE $OUT.new
+cmp -s $OUT $EXP
+status=$?
+
+if [ "$status" = 0 ] ; then
+ echo "$test_name: $test_description: ok"
+ touch $test_name.ok
+else
+ echo "$test_name: $test_description: failed"
+ diff $DIFF_OPTS $EXP $OUT > $test_name.failed
+fi
+
+unset VERIFY_FSCK_OPT NATIVE_FSCK_OPT OUT EXP TEST_DATA VERIFY_DATA
+
+else #if test -x $DEBUGFS_EXE; then
+ echo "$test_name: $test_description: skipped"
+fi
--
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