From 1a8015773a9316ee90f713c275fb3a38731735e4 Mon Sep 17 00:00:00 2001 From: Andreas Dilger Date: Fri, 22 Jun 2018 18:08:54 -0400 Subject: [PATCH] e2fsck: set dir_nlink feature if large dir exists If there is a directory with more than EXT2_LINK_MAX (65000) subdirectories, but the DIR_NLINK feature is not set in the superblock, the feature should be set before continuing on to change the on-disk directory link count to 1. While most filesystems should have DIR_NLINK set (it was set by default for all ext4 filesystems, and all kernels between 2.6.23 and 4.12 automatically set it if the directory link count grew too large), it is possible that this flag is lost due to disk corruption or for an upgraded filesystem. We no longer want kernels to automatically enable features. Addresses: https://bugzilla.kernel.org/show_bug.cgi?id=196405 Signed-off-by: Andreas Dilger Signed-off-by: Theodore Ts'o --- e2fsck/pass4.c | 12 ++++++++- e2fsck/problem.c | 5 ++++ e2fsck/problem.h | 3 +++ tests/f_large_dir/expect | 15 +++++++++-- tests/f_large_dir/script | 67 ++++++++++++++++++++++++++++++++---------------- 5 files changed, 77 insertions(+), 25 deletions(-) diff --git a/e2fsck/pass4.c b/e2fsck/pass4.c index 9a491b1..10be7f8 100644 --- a/e2fsck/pass4.c +++ b/e2fsck/pass4.c @@ -145,6 +145,7 @@ void e2fsck_pass4(e2fsck_t ctx) #endif struct problem_context pctx; __u16 link_count, link_counted; + int dir_nlink_fs; char *buf = 0; dgrp_t group, maxgroup; @@ -168,6 +169,8 @@ void e2fsck_pass4(e2fsck_t ctx) if (!(ctx->options & E2F_OPT_PREEN)) fix_problem(ctx, PR_4_PASS_HEADER, &pctx); + dir_nlink_fs = ext2fs_has_feature_dir_nlink(fs->super); + group = 0; maxgroup = fs->group_desc_count; if (ctx->progress) @@ -224,8 +227,15 @@ void e2fsck_pass4(e2fsck_t ctx) &link_counted); } isdir = ext2fs_test_inode_bitmap2(ctx->inode_dir_map, i); - if (isdir && (link_counted > EXT2_LINK_MAX)) + if (isdir && (link_counted > EXT2_LINK_MAX)) { + if (!dir_nlink_fs && + fix_problem(ctx, PR_4_DIR_NLINK_FEATURE, &pctx)) { + ext2fs_set_feature_dir_nlink(fs->super); + ext2fs_mark_super_dirty(fs); + dir_nlink_fs = 1; + } link_counted = 1; + } if (link_counted != link_count) { e2fsck_read_inode_full(ctx, i, EXT2_INODE(inode), inode_size, "pass4"); diff --git a/e2fsck/problem.c b/e2fsck/problem.c index efe98c9..a98bf8c 100644 --- a/e2fsck/problem.c +++ b/e2fsck/problem.c @@ -1883,6 +1883,11 @@ static struct e2fsck_problem problem_table[] = { N_("@a @i %i ref count is %N, @s %n. "), PROMPT_FIX, PR_PREEN_OK }, + /* directory exceeds max links, but no DIR_NLINK feature in superblock*/ + { PR_4_DIR_NLINK_FEATURE, + N_("@d exceeds max links, but no DIR_NLINK feature in @S.\n"), + PROMPT_FIX, 0 }, + /* Pass 5 errors */ /* Pass 5: Checking group summary information */ diff --git a/e2fsck/problem.h b/e2fsck/problem.h index b6bca66..7db122a 100644 --- a/e2fsck/problem.h +++ b/e2fsck/problem.h @@ -1139,6 +1139,9 @@ struct problem_context { /* Extended attribute inode ref count wrong */ #define PR_4_EA_INODE_REF_COUNT 0x040005 +/* directory exceeds max links, but no DIR_NLINK feature in superblock */ +#define PR_4_DIR_NLINK_FEATURE 0x040006 + /* * Pass 5 errors */ diff --git a/tests/f_large_dir/expect b/tests/f_large_dir/expect index b099460..8f7d99d 100644 --- a/tests/f_large_dir/expect +++ b/tests/f_large_dir/expect @@ -1,12 +1,23 @@ +Creating filesystem with 108341 1k blocks and 65072 inodes +Superblock backups stored on blocks: + 8193, 24577, 40961, 57345, 73729 + +Allocating group tables: done +Writing inode tables: done +Writing superblocks and filesystem accounting information: done + Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 3A: Optimizing directories Pass 4: Checking reference counts -Inode 13 ref count is 1, should be 47245. Fix? yes +Directory exceeds max links, but no DIR_NLINK feature in superblock. +Fix? yes + +Inode 12 ref count is 65012, should be 1. Fix? yes Pass 5: Checking group summary information test.img: ***** FILE SYSTEM WAS MODIFIED ***** -test.img: 13/115368 files (0.0% non-contiguous), 32817/460800 blocks +test.img: 65023/65072 files (0.0% non-contiguous), 96666/108341 blocks Exit status is 1 diff --git a/tests/f_large_dir/script b/tests/f_large_dir/script index e315181..9af042c 100644 --- a/tests/f_large_dir/script +++ b/tests/f_large_dir/script @@ -5,42 +5,65 @@ E2FSCK=../e2fsck/e2fsck NAMELEN=255 DIRENT_SZ=8 BLOCKSZ=1024 +INODESZ=128 DIRENT_PER_LEAF=$((BLOCKSZ / (NAMELEN + DIRENT_SZ))) HEADER=32 INDEX_SZ=8 INDEX_L1=$(((BLOCKSZ - HEADER) / INDEX_SZ)) INDEX_L2=$(((BLOCKSZ - DIRENT_SZ) / INDEX_SZ)) -ENTRIES=$((INDEX_L1 * INDEX_L2 * DIRENT_PER_LEAF)) +DIRBLK=$((2 + INDEX_L1 * INDEX_L2)) +ENTRIES=$((DIRBLK * DIRENT_PER_LEAF)) +EXT4_LINK_MAX=65000 +if [ $ENTRIES -lt $((EXT4_LINK_MAX + 10)) ]; then + ENTRIES=$((EXT4_LINK_MAX + 10)) + DIRBLK=$((ENTRIES / DIRENT_PER_LEAF + 3)) +fi +# directory leaf blocks plus inode count and 25% for the rest of the fs +FSIZE=$(((DIRBLK + EXT4_LINK_MAX * ((BLOCKSZ + INODESZ) / BLOCKSZ)) * 5 / 4)) -$MKE2FS -b 1024 -O large_dir,uninit_bg,dir_nlink -F $TMPFILE 460800 \ - > /dev/null 2>&1 +$MKE2FS -b 1024 -O large_dir,uninit_bg -N $((ENTRIES + 50)) \ + -I $INODESZ -F $TMPFILE $FSIZE > $OUT.new 2>&1 +RC=$? +if [ $RC -eq 0 ]; then { - echo "feature large_dir" + START=$SECONDS echo "mkdir /foo" echo "cd /foo" - touch foofile - echo "write foofile foofile" + touch $TMPFILE.tmp + echo "write $TMPFILE.tmp foofile" i=0 - while test $i -lt $ENTRIES ; do - if test $(( i % DIRENT_PER_LEAF )) -eq 0 ; then - echo "expand ./" + last=0 + while test $i -lt $ENTRIES ; do + if test $((i % DIRENT_PER_LEAF)) -eq 0; then + echo "expand ./" fi - if test $(( i % 5000 )) -eq 0 -a $i -gt 0 ; then - >&2 echo "$test_name: $i/$ENTRIES processed" + ELAPSED=$((SECONDS - START)) + if test $((i % 5000)) -eq 0 -a $ELAPSED -gt 10; then + RATE=$(((i - last) / ELAPSED)) + echo "$test_name: $i/$ENTRIES links, ${ELAPSED}s @ $RATE/s" >&2 + START=$SECONDS + last=$i fi - printf "ln foofile %0255X\n" $i - i=$(($i + 1)) + if test $i -lt $((EXT4_LINK_MAX + 10)); then + printf "mkdir d%0254u\n" $i + else + printf "ln foofile f%0254u\n" $i + fi + i=$((i + 1)) done -} | $DEBUGFS -w $TMPFILE > /dev/null 2>&1 - -$E2FSCK -yfD $TMPFILE > $OUT.new 2>&1 -status=$? -echo Exit status is $status >> $OUT.new -sed -f $cmd_dir/filter.sed -e "s;$TMPFILE;test.img;" $OUT.new > $OUT -rm -f $OUT.new +} | $DEBUGFS -w $TMPFILE > /dev/null 2>> $OUT.new + RC=$? +fi +if [ $RC -eq 0 ]; then + $E2FSCK -yfD $TMPFILE >> $OUT.new 2>&1 + status=$? + echo Exit status is $status >> $OUT.new + sed -f $cmd_dir/filter.sed -e "s;$TMPFILE;test.img;" $OUT.new > $OUT + rm -f $OUT.new -cmp -s $OUT $EXP -RC=$? + cmp -s $OUT $EXP + RC=$? +fi if [ $RC -eq 0 ]; then echo "$test_name: $test_description: ok" touch $test_name.ok -- 1.8.3.1