smbfs_lookup() in the DOTDOT case operates on dvp->n_parent without

proper locking. This doesn't prevent in any case reclaim of the vnode.
Avoid this not going over-the-wire in this case and relying on subsequent
smbfs_getattr() call to restore consistency.
While I'm here, change a couple of SMBVDEBUG() in MPASS().
sbmfs_smb_lookup() doesn't and shouldn't know about '.' and '..'

Reported by:	pho's stress2 suite
This commit is contained in:
davide 2013-03-09 13:25:45 +00:00
parent f30e75d436
commit ce7dfce71d
2 changed files with 16 additions and 15 deletions

View File

@ -1455,15 +1455,9 @@ smbfs_smb_lookup(struct smbnode *dnp, const char *name, int nmlen,
fap->fa_ino = 2;
return 0;
}
if (nmlen == 1 && name[0] == '.') {
error = smbfs_smb_lookup(dnp, NULL, 0, fap, scred);
return error;
} else if (nmlen == 2 && name[0] == '.' && name[1] == '.') {
error = smbfs_smb_lookup(VTOSMB(dnp->n_parent), NULL, 0, fap,
scred);
printf("%s: knows NOTHING about '..'\n", __func__);
return error;
}
MPASS(!(nmlen == 2 && name[0] == '.' && name[1] == '.'));
MPASS(!(nmlen == 1 && name[0] == '.'));
ASSERT_VOP_ELOCKED(dnp->n_vnode, "smbfs_smb_lookup");
error = smbfs_findopen(dnp, name, nmlen,
SMB_FA_SYSTEM | SMB_FA_HIDDEN | SMB_FA_DIR, scred, &ctx);
if (error)

View File

@ -1204,13 +1204,20 @@ smbfs_lookup(ap)
smb_makescred(scred, td, cnp->cn_cred);
fap = &fattr;
if (flags & ISDOTDOT) {
error = smbfs_smb_lookup(VTOSMB(dnp->n_parent), NULL, 0, fap,
scred);
SMBVDEBUG("result of dotdot lookup: %d\n", error);
} else {
fap = &fattr;
/*
* In the DOTDOT case, don't go over-the-wire
* in order to request attributes. We already
* know it's a directory and subsequent call to
* smbfs_getattr() will restore consistency.
*
*/
SMBVDEBUG("smbfs_smb_lookup: dotdot\n");
} else if (isdot) {
error = smbfs_smb_lookup(dnp, NULL, 0, fap, scred);
SMBVDEBUG("result of smbfs_smb_lookup: %d\n", error);
}
else {
error = smbfs_smb_lookup(dnp, name, nmlen, fap, scred);
/* if (cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.')*/
SMBVDEBUG("result of smbfs_smb_lookup: %d\n", error);
}
if (error && error != ENOENT)