diff options
| author | Pranith Kumar K <pkarampu@redhat.com> | 2016-09-23 21:06:37 +0530 |
|---|---|---|
| committer | Pranith Kumar Karampuri <pkarampu@redhat.com> | 2016-10-17 12:00:28 -0700 |
| commit | b5a7dd5b39845d5e58fdd257b5c2bf801c7c1c8a (patch) | |
| tree | fdd6dc8a36dc3cabcaa5b45431d54c357bf781ed /xlators/storage/posix/src | |
| parent | a8b2a981881221925bb5edfe7bb65b25ad855c04 (diff) | |
storage/posix: Fix race in posix_pstat
Problem:
When one thread is in the process of creating a file/directory
and the other thread is doing readdirp, there is a chance that
posix_pstat, creation fops race in the following manner which
will lead to wrong stat values to be read by parent xlators
like posix-acl.
Creation fops posix_pstat() as part of readdirp
1) file is created with uid/gid 0/0 1) does stat of the path that
is created just now.
2) Does chown to set the correct
uid/gid
3) Sets the acl/user/internal xattrs
4) Sets the gfid on the entry and
completes the creation of the file/dir
2) fills the gfid in the iatt
If unwind of readdirp hits server xlator before creation fop, then
posix-acl remembers uid/gid of the file to be root/root and fails
fops like open etc on it.
Fix:
Reverse the order of filling gfid and filling lstat() values in
posix_pstat() so that if there is gfid in iatt buffer uid/gid
are valid.
Change-Id: I46caa7f6da7abfa40a0b1d70e35b88de9c64959c
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
Reviewed-on: http://review.gluster.org/15564
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
Smoke: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Shyamsundar Ranganathan <srangana@redhat.com>
Diffstat (limited to 'xlators/storage/posix/src')
| -rw-r--r-- | xlators/storage/posix/src/posix-helpers.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/xlators/storage/posix/src/posix-helpers.c b/xlators/storage/posix/src/posix-helpers.c index becbd94c226..caa79bf5815 100644 --- a/xlators/storage/posix/src/posix-helpers.c +++ b/xlators/storage/posix/src/posix-helpers.c @@ -632,6 +632,11 @@ posix_pstat (xlator_t *this, uuid_t gfid, const char *path, priv = this->private; + if (gfid && !gf_uuid_is_null (gfid)) + gf_uuid_copy (stbuf.ia_gfid, gfid); + else + posix_fill_gfid_path (this, path, &stbuf); + ret = sys_lstat (path, &lstatbuf); if (ret != 0) { @@ -664,11 +669,6 @@ posix_pstat (xlator_t *this, uuid_t gfid, const char *path, iatt_from_stat (&stbuf, &lstatbuf); - if (gfid && !gf_uuid_is_null (gfid)) - gf_uuid_copy (stbuf.ia_gfid, gfid); - else - posix_fill_gfid_path (this, path, &stbuf); - posix_fill_ino_from_gfid (this, &stbuf); if (buf_p) |