public inbox for glibc-cvs@sourceware.org
help / color / mirror / Atom feed
From: Florian Weimer <fw@sourceware.org>
To: glibc-cvs@sourceware.org
Subject: [glibc] Linux: Do not skip d_ino == 0 entries in readdir, readdir64 (bug 12165)
Date: Mon, 19 Sep 2022 10:05:04 +0000 (GMT) [thread overview]
Message-ID: <20220919100504.127EC3858CDA@sourceware.org> (raw)
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=766b73768b290b303f5b56268c6c0d588d5a9267
commit 766b73768b290b303f5b56268c6c0d588d5a9267
Author: Florian Weimer <fweimer@redhat.com>
Date: Mon Sep 19 08:10:41 2022 +0200
Linux: Do not skip d_ino == 0 entries in readdir, readdir64 (bug 12165)
POSIX does not say this value is special. For example, old XFS file
systems may still use inode number zero.
Also update the comment regarding ENOENT. Linux may return ENOENT
for some file systems.
Diff:
---
sysdeps/unix/sysv/linux/readdir.c | 57 +++++++----------
sysdeps/unix/sysv/linux/readdir64.c | 120 +++++++++++++++---------------------
2 files changed, 69 insertions(+), 108 deletions(-)
diff --git a/sysdeps/unix/sysv/linux/readdir.c b/sysdeps/unix/sysv/linux/readdir.c
index c31f349639..c9a04dc160 100644
--- a/sysdeps/unix/sysv/linux/readdir.c
+++ b/sysdeps/unix/sysv/linux/readdir.c
@@ -28,48 +28,33 @@ __readdir_unlocked (DIR *dirp)
struct dirent *dp;
int saved_errno = errno;
- do
+ if (dirp->offset >= dirp->size)
{
- size_t reclen;
+ /* We've emptied out our buffer. Refill it. */
- if (dirp->offset >= dirp->size)
+ size_t maxread = dirp->allocation;
+ ssize_t bytes;
+
+ bytes = __getdents (dirp->fd, dirp->data, maxread);
+ if (bytes <= 0)
{
- /* We've emptied out our buffer. Refill it. */
-
- size_t maxread = dirp->allocation;
- ssize_t bytes;
-
- bytes = __getdents (dirp->fd, dirp->data, maxread);
- if (bytes <= 0)
- {
- /* On some systems getdents fails with ENOENT when the
- open directory has been rmdir'd already. POSIX.1
- requires that we treat this condition like normal EOF. */
- if (bytes < 0 && errno == ENOENT)
- bytes = 0;
-
- /* Don't modifiy errno when reaching EOF. */
- if (bytes == 0)
- __set_errno (saved_errno);
- dp = NULL;
- break;
- }
- dirp->size = (size_t) bytes;
-
- /* Reset the offset into the buffer. */
- dirp->offset = 0;
+ /* Linux may fail with ENOENT on some file systems if the
+ directory inode is marked as dead (deleted). POSIX
+ treats this as a regular end-of-directory condition, so
+ do not set errno in that case, to indicate success. */
+ if (bytes == 0 || errno == ENOENT)
+ __set_errno (saved_errno);
+ return NULL;
}
+ dirp->size = (size_t) bytes;
- dp = (struct dirent *) &dirp->data[dirp->offset];
-
- reclen = dp->d_reclen;
-
- dirp->offset += reclen;
-
- dirp->filepos = dp->d_off;
+ /* Reset the offset into the buffer. */
+ dirp->offset = 0;
+ }
- /* Skip deleted files. */
- } while (dp->d_ino == 0);
+ dp = (struct dirent *) &dirp->data[dirp->offset];
+ dirp->offset += dp->d_reclen;
+ dirp->filepos = dp->d_off;
return dp;
}
diff --git a/sysdeps/unix/sysv/linux/readdir64.c b/sysdeps/unix/sysv/linux/readdir64.c
index e876d84b02..7952da5c27 100644
--- a/sysdeps/unix/sysv/linux/readdir64.c
+++ b/sysdeps/unix/sysv/linux/readdir64.c
@@ -37,48 +37,36 @@ __readdir64 (DIR *dirp)
__libc_lock_lock (dirp->lock);
#endif
- do
+ if (dirp->offset >= dirp->size)
{
- size_t reclen;
+ /* We've emptied out our buffer. Refill it. */
- if (dirp->offset >= dirp->size)
+ size_t maxread = dirp->allocation;
+ ssize_t bytes;
+
+ bytes = __getdents64 (dirp->fd, dirp->data, maxread);
+ if (bytes <= 0)
{
- /* We've emptied out our buffer. Refill it. */
-
- size_t maxread = dirp->allocation;
- ssize_t bytes;
-
- bytes = __getdents64 (dirp->fd, dirp->data, maxread);
- if (bytes <= 0)
- {
- /* On some systems getdents fails with ENOENT when the
- open directory has been rmdir'd already. POSIX.1
- requires that we treat this condition like normal EOF. */
- if (bytes < 0 && errno == ENOENT)
- bytes = 0;
-
- /* Don't modifiy errno when reaching EOF. */
- if (bytes == 0)
- __set_errno (saved_errno);
- dp = NULL;
- break;
- }
- dirp->size = (size_t) bytes;
-
- /* Reset the offset into the buffer. */
- dirp->offset = 0;
+ /* Linux may fail with ENOENT on some file systems if the
+ directory inode is marked as dead (deleted). POSIX
+ treats this as a regular end-of-directory condition, so
+ do not set errno in that case, to indicate success. */
+ if (bytes == 0 || errno == ENOENT)
+ __set_errno (saved_errno);
+#if IS_IN (libc)
+ __libc_lock_unlock (dirp->lock);
+#endif
+ return NULL;
}
+ dirp->size = (size_t) bytes;
- dp = (struct dirent64 *) &dirp->data[dirp->offset];
-
- reclen = dp->d_reclen;
-
- dirp->offset += reclen;
-
- dirp->filepos = dp->d_off;
+ /* Reset the offset into the buffer. */
+ dirp->offset = 0;
+ }
- /* Skip deleted files. */
- } while (dp->d_ino == 0);
+ dp = (struct dirent64 *) &dirp->data[dirp->offset];
+ dirp->offset += dp->d_reclen;
+ dirp->filepos = dp->d_off;
#if IS_IN (libc)
__libc_lock_unlock (dirp->lock);
@@ -115,48 +103,36 @@ __old_readdir64 (DIR *dirp)
__libc_lock_lock (dirp->lock);
#endif
- do
+ if (dirp->offset >= dirp->size)
{
- size_t reclen;
+ /* We've emptied out our buffer. Refill it. */
- if (dirp->offset >= dirp->size)
+ size_t maxread = dirp->allocation;
+ ssize_t bytes;
+
+ bytes = __old_getdents64 (dirp->fd, dirp->data, maxread);
+ if (bytes <= 0)
{
- /* We've emptied out our buffer. Refill it. */
-
- size_t maxread = dirp->allocation;
- ssize_t bytes;
-
- bytes = __old_getdents64 (dirp->fd, dirp->data, maxread);
- if (bytes <= 0)
- {
- /* On some systems getdents fails with ENOENT when the
- open directory has been rmdir'd already. POSIX.1
- requires that we treat this condition like normal EOF. */
- if (bytes < 0 && errno == ENOENT)
- bytes = 0;
-
- /* Don't modifiy errno when reaching EOF. */
- if (bytes == 0)
- __set_errno (saved_errno);
- dp = NULL;
- break;
- }
- dirp->size = (size_t) bytes;
-
- /* Reset the offset into the buffer. */
- dirp->offset = 0;
+ /* Linux may fail with ENOENT on some file systems if the
+ directory inode is marked as dead (deleted). POSIX
+ treats this as a regular end-of-directory condition, so
+ do not set errno in that case, to indicate success. */
+ if (bytes == 0 || errno == ENOENT)
+ __set_errno (saved_errno);
+#if IS_IN (libc)
+ __libc_lock_unlock (dirp->lock);
+#endif
+ return NULL;
}
+ dirp->size = (size_t) bytes;
- dp = (struct __old_dirent64 *) &dirp->data[dirp->offset];
-
- reclen = dp->d_reclen;
-
- dirp->offset += reclen;
-
- dirp->filepos = dp->d_off;
+ /* Reset the offset into the buffer. */
+ dirp->offset = 0;
+ }
- /* Skip deleted files. */
- } while (dp->d_ino == 0);
+ dp = (struct __old_dirent64 *) &dirp->data[dirp->offset];
+ dirp->offset += dp->d_reclen;
+ dirp->filepos = dp->d_off;
#if IS_IN (libc)
__libc_lock_unlock (dirp->lock);
reply other threads:[~2022-09-19 10:05 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220919100504.127EC3858CDA@sourceware.org \
--to=fw@sourceware.org \
--cc=glibc-cvs@sourceware.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).