Check that directory content read from an open dir fd reflects changes to the directory after open. Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> --- src/t_dir_offset2.c | 63 ++++++++++++++++++++++++++++++++++++++++--- tests/generic/700 | 60 +++++++++++++++++++++++++++++++++++++++++ tests/generic/700.out | 2 ++ tests/generic/group | 1 + 4 files changed, 123 insertions(+), 3 deletions(-) create mode 100755 tests/generic/700 create mode 100644 tests/generic/700.out diff --git a/src/t_dir_offset2.c b/src/t_dir_offset2.c index 5a6d7193..84dab9cf 100644 --- a/src/t_dir_offset2.c +++ b/src/t_dir_offset2.c @@ -13,6 +13,7 @@ #include <unistd.h> #include <stdint.h> #include <stdlib.h> +#include <string.h> #include <sys/stat.h> #include <sys/syscall.h> @@ -26,19 +27,28 @@ struct linux_dirent64 { #define BUF_SIZE 4096 #define HISTORY_LEN 1024 +#define NAME_SIZE 10 static uint64_t d_off_history[HISTORY_LEN]; static uint64_t d_ino_history[HISTORY_LEN]; +static char d_name_history[HISTORY_LEN][NAME_SIZE+1]; + +static int is_dot_or_dot_dot(const char *name) +{ + return !strcmp(name, ".") || !strcmp(name, ".."); +} int main(int argc, char *argv[]) { - int fd, nread; + int fd, nread, nread_0 = 0; char buf[BUF_SIZE]; struct linux_dirent64 *d; int bpos, total, i; off_t lret; int retval = EXIT_SUCCESS; + int create = 0, unlink = 0; + FILE *warn = stderr; fd = open(argv[1], O_RDONLY | O_DIRECTORY); if (fd < 0) { @@ -46,6 +56,15 @@ main(int argc, char *argv[]) exit(EXIT_FAILURE); } + if (argc > 2) { + if (!strcmp(argv[2], "-u")) + unlink = 1; + else + create = 1; + /* Some mismatch warnings are expected */ + warn = stdout; + } + total = 0; for ( ; ; ) { nread = syscall(SYS_getdents64, fd, buf, BUF_SIZE); @@ -54,6 +73,10 @@ main(int argc, char *argv[]) exit(EXIT_FAILURE); } + if (total == 0 && (create || unlink)) { + nread_0 = nread; + printf("getdents at offset 0 returned %d bytes\n", nread); + } if (nread == 0) break; @@ -75,20 +98,40 @@ main(int argc, char *argv[]) } d_off_history[total] = d->d_off; d_ino_history[total] = d->d_ino; + strncpy(d_name_history[total], d->d_name, NAME_SIZE); bpos += d->d_reclen; } } + if (create) { + if (openat(fd, argv[2], O_CREAT, 0600) < 0) { + perror("openat"); + exit(EXIT_FAILURE); + } + printf("created entry %d:%s\n", total, argv[2]); + } + /* check if seek works correctly */ d = (struct linux_dirent64 *)buf; for (i = total - 1; i >= 0; i--) { + const char *name = i > 0 ? d_name_history[i - 1] : NULL; + lret = lseek(fd, i > 0 ? d_off_history[i - 1] : 0, SEEK_SET); if (lret == -1) { perror("lseek"); exit(EXIT_FAILURE); } + /* Unlink prev entry, but not "." nor ".." */ + if (unlink && name && !is_dot_or_dot_dot(name)) { + if (unlinkat(fd, name, 0) < 0) { + perror("unlinkat"); + exit(EXIT_FAILURE); + } + printf("unlinked entry %d:%s\n", i - 1, name); + } + nread = syscall(SYS_getdents64, fd, buf, BUF_SIZE); if (nread == -1) { perror("getdents"); @@ -96,17 +139,31 @@ main(int argc, char *argv[]) } if (nread == 0) { - fprintf(stderr, "getdents returned 0 on entry %d\n", i); + fprintf(warn, "getdents returned 0 on entry %d\n", i); + retval = EXIT_FAILURE; + } + + if (i == 0 && nread_0 && nread != nread_0) { + fprintf(warn, "getdents at offset 0 returned %d bytes, expected %d\n", nread, nread_0); retval = EXIT_FAILURE; } if (d->d_ino != d_ino_history[i]) { - fprintf(stderr, "entry %d has inode %lld, expected %lld\n", + fprintf(warn, "entry %d has inode %lld, expected %lld\n", i, (long long int)d->d_ino, (long long int)d_ino_history[i]); retval = EXIT_FAILURE; } + if (create || unlink) + printf("found entry %d:%s (nread=%d)\n", i, d->d_name, nread); } + /* + * With create/unlink option we expect to find some mismatch with getdents + * before create/unlink, so if everything matches there is something wrong. + */ + if (create || unlink) + retval = retval ? EXIT_SUCCESS : EXIT_FAILURE; + close(fd); exit(retval); } diff --git a/tests/generic/700 b/tests/generic/700 new file mode 100755 index 00000000..eb08958d --- /dev/null +++ b/tests/generic/700 @@ -0,0 +1,60 @@ +#! /bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2021 CTERA Networks. All Rights Reserved. +# +# Check that directory content read from an open dir fd reflects +# changes to the directory after open. +# +seq=`basename $0` +seqres=$RESULT_DIR/$seq +echo "QA output created by $seq" + +here=`pwd` +tmp=/tmp/$$ +status=1 # failure is the default! + +_cleanup() +{ + cd / + rm -f $tmp.* +} +trap "_cleanup; exit \$status" 0 1 2 3 15 + +# get standard environment, filters and checks +. ./common/rc +. ./common/filter + +# real QA test starts here +_supported_fs generic +_require_test + +rm -f $seqres.full + +testdir=$TEST_DIR/test-$seq +rm -rf $testdir +mkdir $testdir + +# Use small number of files that we can assume to be returned in a single +# gendents() call, so t_dir_offset2 can compare the entries count before +# and after seek to start +for n in {1..10}; do + touch $testdir/$n +done + +# Does opendir, readdir, seek to offsets, readdir and +# compares d_ino of entries on second readdir +$here/src/t_dir_offset2 $testdir + +# Check readdir content changes after adding a new file before seek to start +echo "Create file in an open dir:" >> $seqres.full +$here/src/t_dir_offset2 $testdir 0 2>&1 >> $seqres.full || \ + echo "Missing created file in open dir (see $seqres.full for details)" + +# Check readdir content changes after removing files before seek to start +echo "Remove files in an open dir:" >> $seqres.full +$here/src/t_dir_offset2 $testdir -u 2>&1 >> $seqres.full || \ + echo "Found unlinked files in open dir (see $seqres.full for details)" + +# success, all done +echo "Silence is golden" +status=0 diff --git a/tests/generic/700.out b/tests/generic/700.out new file mode 100644 index 00000000..f9acaa71 --- /dev/null +++ b/tests/generic/700.out @@ -0,0 +1,2 @@ +QA output created by 700 +Silence is golden diff --git a/tests/generic/group b/tests/generic/group index ab00cc04..bac5aa48 100644 --- a/tests/generic/group +++ b/tests/generic/group @@ -634,3 +634,4 @@ 629 auto quick rw copy_range 630 auto quick rw dedupe clone 631 auto rw overlay rename +700 auto quick dir -- 2.25.1