lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20190802092102.892371637@linuxfoundation.org>
Date:   Fri,  2 Aug 2019 11:39:37 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Stan Hu <stanhu@...il.com>,
        Trond Myklebust <trond.myklebust@...merspace.com>,
        Qian Lu <luqia@...zon.com>
Subject: [PATCH 4.19 03/32] NFS: Fix dentry revalidation on NFSv4 lookup

From: Trond Myklebust <trond.myklebust@...merspace.com>

commit be189f7e7f03de35887e5a85ddcf39b91b5d7fc1 upstream.

We need to ensure that inode and dentry revalidation occurs correctly
on reopen of a file that is already open. Currently, we can end up
not revalidating either in the case of NFSv4.0, due to the 'cached open'
path.
Let's fix that by ensuring that we only do cached open for the special
cases of open recovery and delegation return.

Reported-by: Stan Hu <stanhu@...il.com>
Signed-off-by: Trond Myklebust <trond.myklebust@...merspace.com>
Signed-off-by: Qian Lu <luqia@...zon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 fs/nfs/nfs4proc.c |   15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1355,12 +1355,20 @@ static bool nfs4_mode_match_open_stateid
 	return false;
 }
 
-static int can_open_cached(struct nfs4_state *state, fmode_t mode, int open_mode)
+static int can_open_cached(struct nfs4_state *state, fmode_t mode,
+		int open_mode, enum open_claim_type4 claim)
 {
 	int ret = 0;
 
 	if (open_mode & (O_EXCL|O_TRUNC))
 		goto out;
+	switch (claim) {
+	case NFS4_OPEN_CLAIM_NULL:
+	case NFS4_OPEN_CLAIM_FH:
+		goto out;
+	default:
+		break;
+	}
 	switch (mode & (FMODE_READ|FMODE_WRITE)) {
 		case FMODE_READ:
 			ret |= test_bit(NFS_O_RDONLY_STATE, &state->flags) != 0
@@ -1753,7 +1761,7 @@ static struct nfs4_state *nfs4_try_open_
 
 	for (;;) {
 		spin_lock(&state->owner->so_lock);
-		if (can_open_cached(state, fmode, open_mode)) {
+		if (can_open_cached(state, fmode, open_mode, claim)) {
 			update_open_stateflags(state, fmode);
 			spin_unlock(&state->owner->so_lock);
 			goto out_return_state;
@@ -2282,7 +2290,8 @@ static void nfs4_open_prepare(struct rpc
 	if (data->state != NULL) {
 		struct nfs_delegation *delegation;
 
-		if (can_open_cached(data->state, data->o_arg.fmode, data->o_arg.open_flags))
+		if (can_open_cached(data->state, data->o_arg.fmode,
+					data->o_arg.open_flags, claim))
 			goto out_no_action;
 		rcu_read_lock();
 		delegation = rcu_dereference(NFS_I(data->state->inode)->delegation);


Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ