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From: Fredric Cover <fredric.cover.lkernel@gmail.com>
To: sfrench@samba.org
Cc: pc@manguebit.org, ronniesahlberg@gmail.com,
	sprasad@microsoft.com, tom@talpey.com, bharathsm@microsoft.com,
	linux-cifs@vger.kernel.org, linux-kernel@vger.kernel.org,
	Fredric Cover <fredric.cover.lkernel@gmail.com>
Subject: [PATCH v3 0/2] smb: client: fix dangling pointer in DFS target hints
Date: Fri, 24 Jul 2026 15:01:44 -0700	[thread overview]
Message-ID: <20260724220146.1859170-1-fredric.cover.lkernel@gmail.com> (raw)
In-Reply-To: <20260724023539.1596955-1-fredric.cover.lkernel@gmail.com>

This series addresses a Use-After-Free bug where ce->tgthint was left
pointing to freed memory after free_tgts() was called.

To fix this, Patch 1 hardens the DFS cache readers against ce->tgthint
being NULL. Also, Patch 1 hardens callers of get_tgt_name(), which
returns an error pointer when ce->tgthint is NULL.

Patch 2 clears ce->tgthint in free_tgts(), eliminating the dangling
pointer.

v2 -> v3:
 - Resent series with proper thread structure and subject headers.

v1 -> v2:
 - Addressed automated review by Sashiko:
   https://sashiko.dev/#/patchset/20260724023539.1596955-1-fredric.cover.lkernel%40gmail.com
 - Split into a 2-patch series to harden readers against NULL and
   ERR_PTR target hints.

Fredric Cover (2):
  smb: client: harden DFS cache against invalid target hints
  smb: client: clear ce->tgthint in free_tgts()

 fs/smb/client/dfs_cache.c | 33 ++++++++++++++++++++++++++-------
 1 file changed, 26 insertions(+), 7 deletions(-)

-- 
2.53.0


  parent reply	other threads:[~2026-07-24 22:02 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-07-24  2:35 [PATCH] smb: client: clear ce->tgthint in free_tgts() Fredric Cover
2026-07-24 21:44 ` [PATCH v2 0/2] smb: client: fix dangling pointer in DFS target hints Fredric Cover
2026-07-24 21:44   ` [PATCH v2 1/2] smb: client: harden DFS cache against invalid " Fredric Cover
2026-07-24 21:44   ` [PATCH v2 2/2] smb: client: clear ce->tgthint in free_tgts() Fredric Cover
2026-07-24 22:01 ` Fredric Cover [this message]
2026-07-24 22:01   ` [PATCH v3 1/2] smb: client: harden DFS cache against invalid target hints Fredric Cover
2026-07-24 22:01   ` [PATCH v3 2/2] smb: client: clear ce->tgthint in free_tgts() Fredric Cover

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