The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 99f855082f228cdcecd6ab768d3b8b505e0eb028
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024040803-tackling-bogged-527d@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
99f855082f22 ("drm/i915/mst: Reject FEC+MST on ICL")
126f94e87e79 ("drm/i915: Fix FEC pipe A vs. DDI A mixup")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 99f855082f228cdcecd6ab768d3b8b505e0eb028 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala(a)linux.intel.com>
Date: Tue, 2 Apr 2024 16:51:47 +0300
Subject: [PATCH] drm/i915/mst: Reject FEC+MST on ICL
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
ICL supposedly doesn't support FEC on MST. Reject it.
Cc: stable(a)vger.kernel.org
Fixes: d51f25eb479a ("drm/i915: Add DSC support to MST path")
Reviewed-by: Uma Shankar <uma.shankar(a)intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240402135148.23011-7-ville.…
(cherry picked from commit b648ce2a28ba83c4fa67c61fcc5983e15e9d4afb)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi(a)intel.com>
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 36afbb68d87d..abd62bebc46d 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -1422,7 +1422,8 @@ static bool intel_dp_source_supports_fec(struct intel_dp *intel_dp,
if (DISPLAY_VER(dev_priv) >= 12)
return true;
- if (DISPLAY_VER(dev_priv) == 11 && encoder->port != PORT_A)
+ if (DISPLAY_VER(dev_priv) == 11 && encoder->port != PORT_A &&
+ !intel_crtc_has_type(pipe_config, INTEL_OUTPUT_DP_MST))
return true;
return false;
The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 51bc63392e96ca45d7be98bc43c180b174ffca09
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024040851-nail-pectin-26a4@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
51bc63392e96 ("drm/i915/mst: Limit MST+DSC to TGL+")
d19daffc89fe ("drm/i915/dp_mst: Use connector DSC DPCD in intel_dp_mst_mode_valid_ctx()")
8d5284765a43 ("drm/i915/dp: Use consistent name for link bpp and compressed bpp")
3a4b4809c8cc ("drm/i915/dp: Move compressed bpp check with 420 format inside the helper")
a1476c2a9715 ("drm/i915/dp: Consider output_format while computing dsc bpp")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 51bc63392e96ca45d7be98bc43c180b174ffca09 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala(a)linux.intel.com>
Date: Tue, 2 Apr 2024 16:51:46 +0300
Subject: [PATCH] drm/i915/mst: Limit MST+DSC to TGL+
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
The MST code currently assumes that glk+ already supports MST+DSC,
which is incorrect. We need to check for TGL+ actually. ICL does
support SST+DSC, but supposedly it can't do MST+FEC which will
also rule out MST+DSC.
Note that a straight TGL+ check doesn't work here because DSC
support can get fused out, so we do need to also check 'has_dsc'.
Cc: stable(a)vger.kernel.org
Fixes: d51f25eb479a ("drm/i915: Add DSC support to MST path")
Reviewed-by: Uma Shankar <uma.shankar(a)intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240402135148.23011-6-ville.…
(cherry picked from commit c9c92f286dbdf872390ef3e74dbe5f0641e46f55)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi(a)intel.com>
diff --git a/drivers/gpu/drm/i915/display/intel_display_device.h b/drivers/gpu/drm/i915/display/intel_display_device.h
index fe4268813786..9b1bce2624b9 100644
--- a/drivers/gpu/drm/i915/display/intel_display_device.h
+++ b/drivers/gpu/drm/i915/display/intel_display_device.h
@@ -47,6 +47,7 @@ struct drm_printer;
#define HAS_DPT(i915) (DISPLAY_VER(i915) >= 13)
#define HAS_DSB(i915) (DISPLAY_INFO(i915)->has_dsb)
#define HAS_DSC(__i915) (DISPLAY_RUNTIME_INFO(__i915)->has_dsc)
+#define HAS_DSC_MST(__i915) (DISPLAY_VER(__i915) >= 12 && HAS_DSC(__i915))
#define HAS_FBC(i915) (DISPLAY_RUNTIME_INFO(i915)->fbc_mask != 0)
#define HAS_FPGA_DBG_UNCLAIMED(i915) (DISPLAY_INFO(i915)->has_fpga_dbg)
#define HAS_FW_BLC(i915) (DISPLAY_VER(i915) >= 3)
diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index 53aec023ce92..b651c990af85 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -1355,7 +1355,7 @@ intel_dp_mst_mode_valid_ctx(struct drm_connector *connector,
return 0;
}
- if (DISPLAY_VER(dev_priv) >= 10 &&
+ if (HAS_DSC_MST(dev_priv) &&
drm_dp_sink_supports_dsc(intel_connector->dp.dsc_dpcd)) {
/*
* TBD pass the connector BPC,
The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 58acd1f497162e7d282077f816faa519487be045
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024040829-upcoming-gnat-69ec@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
58acd1f49716 ("smb: client: fix potential UAF in cifs_dump_full_key()")
38c8a9a52082 ("smb: move client and server files to common directory fs/smb")
8e3554150d6c ("cifs: fix sharing of DFS connections")
2f4e429c8469 ("cifs: lock chan_lock outside match_session")
396935de1455 ("cifs: fix use-after-free bug in refresh_cache_worker()")
b56bce502f55 ("cifs: set DFS root session in cifs_get_smb_ses()")
b9ee2e307c6b ("cifs: improve checking of DFS links over STATUS_OBJECT_NAME_INVALID")
7ad54b98fc1f ("cifs: use origin fullpath for automounts")
466611e4af82 ("cifs: fix source pathname comparison of dfs supers")
6916881f443f ("cifs: fix refresh of cached referrals")
cb3f6d876452 ("cifs: don't refresh cached referrals from unactive mounts")
a1c0d00572fc ("cifs: share dfs connections and supers")
a73a26d97eca ("cifs: split out ses and tcon retrieval from mount_get_conns()")
2301bc103ac4 ("cifs: remove unused smb3_fs_context::mount_options")
abdb1742a312 ("cifs: get rid of mount options string parsing")
9fd29a5bae6e ("cifs: use fs_context for automounts")
c877ce47e137 ("cifs: reduce roundtrips on create/qinfo requests")
83fb8abec293 ("cifs: Add "extbuf" and "extbuflen" args to smb2_compound_op()")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 58acd1f497162e7d282077f816faa519487be045 Mon Sep 17 00:00:00 2001
From: Paulo Alcantara <pc(a)manguebit.com>
Date: Tue, 2 Apr 2024 16:33:54 -0300
Subject: [PATCH] smb: client: fix potential UAF in cifs_dump_full_key()
Skip sessions that are being teared down (status == SES_EXITING) to
avoid UAF.
Cc: stable(a)vger.kernel.org
Signed-off-by: Paulo Alcantara (Red Hat) <pc(a)manguebit.com>
Signed-off-by: Steve French <stfrench(a)microsoft.com>
diff --git a/fs/smb/client/ioctl.c b/fs/smb/client/ioctl.c
index c012dfdba80d..855ac5a62edf 100644
--- a/fs/smb/client/ioctl.c
+++ b/fs/smb/client/ioctl.c
@@ -247,7 +247,9 @@ static int cifs_dump_full_key(struct cifs_tcon *tcon, struct smb3_full_key_debug
spin_lock(&cifs_tcp_ses_lock);
list_for_each_entry(server_it, &cifs_tcp_ses_list, tcp_ses_list) {
list_for_each_entry(ses_it, &server_it->smb_ses_list, smb_ses_list) {
- if (ses_it->Suid == out.session_id) {
+ spin_lock(&ses_it->ses_lock);
+ if (ses_it->ses_status != SES_EXITING &&
+ ses_it->Suid == out.session_id) {
ses = ses_it;
/*
* since we are using the session outside the crit
@@ -255,9 +257,11 @@ static int cifs_dump_full_key(struct cifs_tcon *tcon, struct smb3_full_key_debug
* so increment its refcount
*/
cifs_smb_ses_inc_refcount(ses);
+ spin_unlock(&ses_it->ses_lock);
found = true;
goto search_end;
}
+ spin_unlock(&ses_it->ses_lock);
}
}
search_end:
The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y
git checkout FETCH_HEAD
git cherry-pick -x 24a9799aa8efecd0eb55a75e35f9d8e6400063aa
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024040843-empathic-duller-2cb9@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..
Possible dependencies:
24a9799aa8ef ("smb: client: fix UAF in smb2_reconnect_server()")
7257bcf3bdc7 ("cifs: cifs_chan_is_iface_active should be called with chan_lock held")
27e1fd343f80 ("cifs: after disabling multichannel, mark tcon for reconnect")
fa1d0508bdd4 ("cifs: account for primary channel in the interface list")
a6d8fb54a515 ("cifs: distribute channels across interfaces based on speed")
c37ed2d7d098 ("smb: client: remove extra @chan_count check in __cifs_put_smb_ses()")
ff7d80a9f271 ("cifs: fix session state transition to avoid use-after-free issue")
38c8a9a52082 ("smb: move client and server files to common directory fs/smb")
943fb67b0902 ("cifs: missing lock when updating session status")
bc962159e8e3 ("cifs: avoid race conditions with parallel reconnects")
1bcd548d935a ("cifs: prevent data race in cifs_reconnect_tcon()")
e77978de4765 ("cifs: update ip_addr for ses only for primary chan setup")
3c0070f54b31 ("cifs: prevent data race in smb2_reconnect()")
05844bd661d9 ("cifs: print last update time for interface list")
25cf01b7c920 ("cifs: set correct status of tcon ipc when reconnecting")
abdb1742a312 ("cifs: get rid of mount options string parsing")
9fd29a5bae6e ("cifs: use fs_context for automounts")
f391d6ee002e ("cifs: Use after free in debug code")
68e14569d7e5 ("smb3: add dynamic trace points for tree disconnect")
13609a8b3ac6 ("cifs: move from strlcpy with unused retval to strscpy")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 24a9799aa8efecd0eb55a75e35f9d8e6400063aa Mon Sep 17 00:00:00 2001
From: Paulo Alcantara <pc(a)manguebit.com>
Date: Mon, 1 Apr 2024 14:13:10 -0300
Subject: [PATCH] smb: client: fix UAF in smb2_reconnect_server()
The UAF bug is due to smb2_reconnect_server() accessing a session that
is already being teared down by another thread that is executing
__cifs_put_smb_ses(). This can happen when (a) the client has
connection to the server but no session or (b) another thread ends up
setting @ses->ses_status again to something different than
SES_EXITING.
To fix this, we need to make sure to unconditionally set
@ses->ses_status to SES_EXITING and prevent any other threads from
setting a new status while we're still tearing it down.
The following can be reproduced by adding some delay to right after
the ipc is freed in __cifs_put_smb_ses() - which will give
smb2_reconnect_server() worker a chance to run and then accessing
@ses->ipc:
kinit ...
mount.cifs //srv/share /mnt/1 -o sec=krb5,nohandlecache,echo_interval=10
[disconnect srv]
ls /mnt/1 &>/dev/null
sleep 30
kdestroy
[reconnect srv]
sleep 10
umount /mnt/1
...
CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed
CIFS: VFS: \\srv Send error in SessSetup = -126
CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed
CIFS: VFS: \\srv Send error in SessSetup = -126
general protection fault, probably for non-canonical address
0x6b6b6b6b6b6b6b6b: 0000 [#1] PREEMPT SMP NOPTI
CPU: 3 PID: 50 Comm: kworker/3:1 Not tainted 6.9.0-rc2 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-1.fc39
04/01/2014
Workqueue: cifsiod smb2_reconnect_server [cifs]
RIP: 0010:__list_del_entry_valid_or_report+0x33/0xf0
Code: 4f 08 48 85 d2 74 42 48 85 c9 74 59 48 b8 00 01 00 00 00 00 ad
de 48 39 c2 74 61 48 b8 22 01 00 00 00 00 74 69 <48> 8b 01 48 39 f8 75
7b 48 8b 72 08 48 39 c6 0f 85 88 00 00 00 b8
RSP: 0018:ffffc900001bfd70 EFLAGS: 00010a83
RAX: dead000000000122 RBX: ffff88810da53838 RCX: 6b6b6b6b6b6b6b6b
RDX: 6b6b6b6b6b6b6b6b RSI: ffffffffc02f6878 RDI: ffff88810da53800
RBP: ffff88810da53800 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88810c064000
R13: 0000000000000001 R14: ffff88810c064000 R15: ffff8881039cc000
FS: 0000000000000000(0000) GS:ffff888157c00000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe3728b1000 CR3: 000000010caa4000 CR4: 0000000000750ef0
PKRU: 55555554
Call Trace:
<TASK>
? die_addr+0x36/0x90
? exc_general_protection+0x1c1/0x3f0
? asm_exc_general_protection+0x26/0x30
? __list_del_entry_valid_or_report+0x33/0xf0
__cifs_put_smb_ses+0x1ae/0x500 [cifs]
smb2_reconnect_server+0x4ed/0x710 [cifs]
process_one_work+0x205/0x6b0
worker_thread+0x191/0x360
? __pfx_worker_thread+0x10/0x10
kthread+0xe2/0x110
? __pfx_kthread+0x10/0x10
ret_from_fork+0x34/0x50
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
Cc: stable(a)vger.kernel.org
Signed-off-by: Paulo Alcantara (Red Hat) <pc(a)manguebit.com>
Signed-off-by: Steve French <stfrench(a)microsoft.com>
diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c
index 9b85b5341822..ee29bc57300c 100644
--- a/fs/smb/client/connect.c
+++ b/fs/smb/client/connect.c
@@ -232,7 +232,13 @@ cifs_mark_tcp_ses_conns_for_reconnect(struct TCP_Server_Info *server,
spin_lock(&cifs_tcp_ses_lock);
list_for_each_entry_safe(ses, nses, &pserver->smb_ses_list, smb_ses_list) {
- /* check if iface is still active */
+ spin_lock(&ses->ses_lock);
+ if (ses->ses_status == SES_EXITING) {
+ spin_unlock(&ses->ses_lock);
+ continue;
+ }
+ spin_unlock(&ses->ses_lock);
+
spin_lock(&ses->chan_lock);
if (cifs_ses_get_chan_index(ses, server) ==
CIFS_INVAL_CHAN_INDEX) {
@@ -1963,31 +1969,6 @@ cifs_setup_ipc(struct cifs_ses *ses, struct smb3_fs_context *ctx)
return rc;
}
-/**
- * cifs_free_ipc - helper to release the session IPC tcon
- * @ses: smb session to unmount the IPC from
- *
- * Needs to be called everytime a session is destroyed.
- *
- * On session close, the IPC is closed and the server must release all tcons of the session.
- * No need to send a tree disconnect here.
- *
- * Besides, it will make the server to not close durable and resilient files on session close, as
- * specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
- */
-static int
-cifs_free_ipc(struct cifs_ses *ses)
-{
- struct cifs_tcon *tcon = ses->tcon_ipc;
-
- if (tcon == NULL)
- return 0;
-
- tconInfoFree(tcon);
- ses->tcon_ipc = NULL;
- return 0;
-}
-
static struct cifs_ses *
cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
{
@@ -2019,48 +2000,52 @@ cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
void __cifs_put_smb_ses(struct cifs_ses *ses)
{
struct TCP_Server_Info *server = ses->server;
+ struct cifs_tcon *tcon;
unsigned int xid;
size_t i;
+ bool do_logoff;
int rc;
- spin_lock(&ses->ses_lock);
- if (ses->ses_status == SES_EXITING) {
- spin_unlock(&ses->ses_lock);
- return;
- }
- spin_unlock(&ses->ses_lock);
-
- cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
- cifs_dbg(FYI,
- "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->tree_name : "NONE");
-
spin_lock(&cifs_tcp_ses_lock);
- if (--ses->ses_count > 0) {
+ spin_lock(&ses->ses_lock);
+ cifs_dbg(FYI, "%s: id=0x%llx ses_count=%d ses_status=%u ipc=%s\n",
+ __func__, ses->Suid, ses->ses_count, ses->ses_status,
+ ses->tcon_ipc ? ses->tcon_ipc->tree_name : "none");
+ if (ses->ses_status == SES_EXITING || --ses->ses_count > 0) {
+ spin_unlock(&ses->ses_lock);
spin_unlock(&cifs_tcp_ses_lock);
return;
}
- spin_lock(&ses->ses_lock);
- if (ses->ses_status == SES_GOOD)
- ses->ses_status = SES_EXITING;
- spin_unlock(&ses->ses_lock);
- spin_unlock(&cifs_tcp_ses_lock);
-
/* ses_count can never go negative */
WARN_ON(ses->ses_count < 0);
- spin_lock(&ses->ses_lock);
- if (ses->ses_status == SES_EXITING && server->ops->logoff) {
- spin_unlock(&ses->ses_lock);
- cifs_free_ipc(ses);
+ spin_lock(&ses->chan_lock);
+ cifs_chan_clear_need_reconnect(ses, server);
+ spin_unlock(&ses->chan_lock);
+
+ do_logoff = ses->ses_status == SES_GOOD && server->ops->logoff;
+ ses->ses_status = SES_EXITING;
+ tcon = ses->tcon_ipc;
+ ses->tcon_ipc = NULL;
+ spin_unlock(&ses->ses_lock);
+ spin_unlock(&cifs_tcp_ses_lock);
+
+ /*
+ * On session close, the IPC is closed and the server must release all
+ * tcons of the session. No need to send a tree disconnect here.
+ *
+ * Besides, it will make the server to not close durable and resilient
+ * files on session close, as specified in MS-SMB2 3.3.5.6 Receiving an
+ * SMB2 LOGOFF Request.
+ */
+ tconInfoFree(tcon);
+ if (do_logoff) {
xid = get_xid();
rc = server->ops->logoff(xid, ses);
if (rc)
cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
__func__, rc);
_free_xid(xid);
- } else {
- spin_unlock(&ses->ses_lock);
- cifs_free_ipc(ses);
}
spin_lock(&cifs_tcp_ses_lock);
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 24a9799aa8efecd0eb55a75e35f9d8e6400063aa
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024040841-scarcity-subarctic-4f20@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
24a9799aa8ef ("smb: client: fix UAF in smb2_reconnect_server()")
7257bcf3bdc7 ("cifs: cifs_chan_is_iface_active should be called with chan_lock held")
27e1fd343f80 ("cifs: after disabling multichannel, mark tcon for reconnect")
fa1d0508bdd4 ("cifs: account for primary channel in the interface list")
a6d8fb54a515 ("cifs: distribute channels across interfaces based on speed")
c37ed2d7d098 ("smb: client: remove extra @chan_count check in __cifs_put_smb_ses()")
ff7d80a9f271 ("cifs: fix session state transition to avoid use-after-free issue")
38c8a9a52082 ("smb: move client and server files to common directory fs/smb")
943fb67b0902 ("cifs: missing lock when updating session status")
bc962159e8e3 ("cifs: avoid race conditions with parallel reconnects")
1bcd548d935a ("cifs: prevent data race in cifs_reconnect_tcon()")
e77978de4765 ("cifs: update ip_addr for ses only for primary chan setup")
3c0070f54b31 ("cifs: prevent data race in smb2_reconnect()")
05844bd661d9 ("cifs: print last update time for interface list")
25cf01b7c920 ("cifs: set correct status of tcon ipc when reconnecting")
abdb1742a312 ("cifs: get rid of mount options string parsing")
9fd29a5bae6e ("cifs: use fs_context for automounts")
f391d6ee002e ("cifs: Use after free in debug code")
68e14569d7e5 ("smb3: add dynamic trace points for tree disconnect")
13609a8b3ac6 ("cifs: move from strlcpy with unused retval to strscpy")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 24a9799aa8efecd0eb55a75e35f9d8e6400063aa Mon Sep 17 00:00:00 2001
From: Paulo Alcantara <pc(a)manguebit.com>
Date: Mon, 1 Apr 2024 14:13:10 -0300
Subject: [PATCH] smb: client: fix UAF in smb2_reconnect_server()
The UAF bug is due to smb2_reconnect_server() accessing a session that
is already being teared down by another thread that is executing
__cifs_put_smb_ses(). This can happen when (a) the client has
connection to the server but no session or (b) another thread ends up
setting @ses->ses_status again to something different than
SES_EXITING.
To fix this, we need to make sure to unconditionally set
@ses->ses_status to SES_EXITING and prevent any other threads from
setting a new status while we're still tearing it down.
The following can be reproduced by adding some delay to right after
the ipc is freed in __cifs_put_smb_ses() - which will give
smb2_reconnect_server() worker a chance to run and then accessing
@ses->ipc:
kinit ...
mount.cifs //srv/share /mnt/1 -o sec=krb5,nohandlecache,echo_interval=10
[disconnect srv]
ls /mnt/1 &>/dev/null
sleep 30
kdestroy
[reconnect srv]
sleep 10
umount /mnt/1
...
CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed
CIFS: VFS: \\srv Send error in SessSetup = -126
CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed
CIFS: VFS: \\srv Send error in SessSetup = -126
general protection fault, probably for non-canonical address
0x6b6b6b6b6b6b6b6b: 0000 [#1] PREEMPT SMP NOPTI
CPU: 3 PID: 50 Comm: kworker/3:1 Not tainted 6.9.0-rc2 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-1.fc39
04/01/2014
Workqueue: cifsiod smb2_reconnect_server [cifs]
RIP: 0010:__list_del_entry_valid_or_report+0x33/0xf0
Code: 4f 08 48 85 d2 74 42 48 85 c9 74 59 48 b8 00 01 00 00 00 00 ad
de 48 39 c2 74 61 48 b8 22 01 00 00 00 00 74 69 <48> 8b 01 48 39 f8 75
7b 48 8b 72 08 48 39 c6 0f 85 88 00 00 00 b8
RSP: 0018:ffffc900001bfd70 EFLAGS: 00010a83
RAX: dead000000000122 RBX: ffff88810da53838 RCX: 6b6b6b6b6b6b6b6b
RDX: 6b6b6b6b6b6b6b6b RSI: ffffffffc02f6878 RDI: ffff88810da53800
RBP: ffff88810da53800 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88810c064000
R13: 0000000000000001 R14: ffff88810c064000 R15: ffff8881039cc000
FS: 0000000000000000(0000) GS:ffff888157c00000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe3728b1000 CR3: 000000010caa4000 CR4: 0000000000750ef0
PKRU: 55555554
Call Trace:
<TASK>
? die_addr+0x36/0x90
? exc_general_protection+0x1c1/0x3f0
? asm_exc_general_protection+0x26/0x30
? __list_del_entry_valid_or_report+0x33/0xf0
__cifs_put_smb_ses+0x1ae/0x500 [cifs]
smb2_reconnect_server+0x4ed/0x710 [cifs]
process_one_work+0x205/0x6b0
worker_thread+0x191/0x360
? __pfx_worker_thread+0x10/0x10
kthread+0xe2/0x110
? __pfx_kthread+0x10/0x10
ret_from_fork+0x34/0x50
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
Cc: stable(a)vger.kernel.org
Signed-off-by: Paulo Alcantara (Red Hat) <pc(a)manguebit.com>
Signed-off-by: Steve French <stfrench(a)microsoft.com>
diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c
index 9b85b5341822..ee29bc57300c 100644
--- a/fs/smb/client/connect.c
+++ b/fs/smb/client/connect.c
@@ -232,7 +232,13 @@ cifs_mark_tcp_ses_conns_for_reconnect(struct TCP_Server_Info *server,
spin_lock(&cifs_tcp_ses_lock);
list_for_each_entry_safe(ses, nses, &pserver->smb_ses_list, smb_ses_list) {
- /* check if iface is still active */
+ spin_lock(&ses->ses_lock);
+ if (ses->ses_status == SES_EXITING) {
+ spin_unlock(&ses->ses_lock);
+ continue;
+ }
+ spin_unlock(&ses->ses_lock);
+
spin_lock(&ses->chan_lock);
if (cifs_ses_get_chan_index(ses, server) ==
CIFS_INVAL_CHAN_INDEX) {
@@ -1963,31 +1969,6 @@ cifs_setup_ipc(struct cifs_ses *ses, struct smb3_fs_context *ctx)
return rc;
}
-/**
- * cifs_free_ipc - helper to release the session IPC tcon
- * @ses: smb session to unmount the IPC from
- *
- * Needs to be called everytime a session is destroyed.
- *
- * On session close, the IPC is closed and the server must release all tcons of the session.
- * No need to send a tree disconnect here.
- *
- * Besides, it will make the server to not close durable and resilient files on session close, as
- * specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
- */
-static int
-cifs_free_ipc(struct cifs_ses *ses)
-{
- struct cifs_tcon *tcon = ses->tcon_ipc;
-
- if (tcon == NULL)
- return 0;
-
- tconInfoFree(tcon);
- ses->tcon_ipc = NULL;
- return 0;
-}
-
static struct cifs_ses *
cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
{
@@ -2019,48 +2000,52 @@ cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
void __cifs_put_smb_ses(struct cifs_ses *ses)
{
struct TCP_Server_Info *server = ses->server;
+ struct cifs_tcon *tcon;
unsigned int xid;
size_t i;
+ bool do_logoff;
int rc;
- spin_lock(&ses->ses_lock);
- if (ses->ses_status == SES_EXITING) {
- spin_unlock(&ses->ses_lock);
- return;
- }
- spin_unlock(&ses->ses_lock);
-
- cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
- cifs_dbg(FYI,
- "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->tree_name : "NONE");
-
spin_lock(&cifs_tcp_ses_lock);
- if (--ses->ses_count > 0) {
+ spin_lock(&ses->ses_lock);
+ cifs_dbg(FYI, "%s: id=0x%llx ses_count=%d ses_status=%u ipc=%s\n",
+ __func__, ses->Suid, ses->ses_count, ses->ses_status,
+ ses->tcon_ipc ? ses->tcon_ipc->tree_name : "none");
+ if (ses->ses_status == SES_EXITING || --ses->ses_count > 0) {
+ spin_unlock(&ses->ses_lock);
spin_unlock(&cifs_tcp_ses_lock);
return;
}
- spin_lock(&ses->ses_lock);
- if (ses->ses_status == SES_GOOD)
- ses->ses_status = SES_EXITING;
- spin_unlock(&ses->ses_lock);
- spin_unlock(&cifs_tcp_ses_lock);
-
/* ses_count can never go negative */
WARN_ON(ses->ses_count < 0);
- spin_lock(&ses->ses_lock);
- if (ses->ses_status == SES_EXITING && server->ops->logoff) {
- spin_unlock(&ses->ses_lock);
- cifs_free_ipc(ses);
+ spin_lock(&ses->chan_lock);
+ cifs_chan_clear_need_reconnect(ses, server);
+ spin_unlock(&ses->chan_lock);
+
+ do_logoff = ses->ses_status == SES_GOOD && server->ops->logoff;
+ ses->ses_status = SES_EXITING;
+ tcon = ses->tcon_ipc;
+ ses->tcon_ipc = NULL;
+ spin_unlock(&ses->ses_lock);
+ spin_unlock(&cifs_tcp_ses_lock);
+
+ /*
+ * On session close, the IPC is closed and the server must release all
+ * tcons of the session. No need to send a tree disconnect here.
+ *
+ * Besides, it will make the server to not close durable and resilient
+ * files on session close, as specified in MS-SMB2 3.3.5.6 Receiving an
+ * SMB2 LOGOFF Request.
+ */
+ tconInfoFree(tcon);
+ if (do_logoff) {
xid = get_xid();
rc = server->ops->logoff(xid, ses);
if (rc)
cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
__func__, rc);
_free_xid(xid);
- } else {
- spin_unlock(&ses->ses_lock);
- cifs_free_ipc(ses);
}
spin_lock(&cifs_tcp_ses_lock);
The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 24a9799aa8efecd0eb55a75e35f9d8e6400063aa
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024040839-drainage-uninvited-614e@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
24a9799aa8ef ("smb: client: fix UAF in smb2_reconnect_server()")
7257bcf3bdc7 ("cifs: cifs_chan_is_iface_active should be called with chan_lock held")
27e1fd343f80 ("cifs: after disabling multichannel, mark tcon for reconnect")
fa1d0508bdd4 ("cifs: account for primary channel in the interface list")
a6d8fb54a515 ("cifs: distribute channels across interfaces based on speed")
c37ed2d7d098 ("smb: client: remove extra @chan_count check in __cifs_put_smb_ses()")
ff7d80a9f271 ("cifs: fix session state transition to avoid use-after-free issue")
38c8a9a52082 ("smb: move client and server files to common directory fs/smb")
943fb67b0902 ("cifs: missing lock when updating session status")
bc962159e8e3 ("cifs: avoid race conditions with parallel reconnects")
1bcd548d935a ("cifs: prevent data race in cifs_reconnect_tcon()")
e77978de4765 ("cifs: update ip_addr for ses only for primary chan setup")
3c0070f54b31 ("cifs: prevent data race in smb2_reconnect()")
05844bd661d9 ("cifs: print last update time for interface list")
25cf01b7c920 ("cifs: set correct status of tcon ipc when reconnecting")
abdb1742a312 ("cifs: get rid of mount options string parsing")
9fd29a5bae6e ("cifs: use fs_context for automounts")
f391d6ee002e ("cifs: Use after free in debug code")
68e14569d7e5 ("smb3: add dynamic trace points for tree disconnect")
13609a8b3ac6 ("cifs: move from strlcpy with unused retval to strscpy")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 24a9799aa8efecd0eb55a75e35f9d8e6400063aa Mon Sep 17 00:00:00 2001
From: Paulo Alcantara <pc(a)manguebit.com>
Date: Mon, 1 Apr 2024 14:13:10 -0300
Subject: [PATCH] smb: client: fix UAF in smb2_reconnect_server()
The UAF bug is due to smb2_reconnect_server() accessing a session that
is already being teared down by another thread that is executing
__cifs_put_smb_ses(). This can happen when (a) the client has
connection to the server but no session or (b) another thread ends up
setting @ses->ses_status again to something different than
SES_EXITING.
To fix this, we need to make sure to unconditionally set
@ses->ses_status to SES_EXITING and prevent any other threads from
setting a new status while we're still tearing it down.
The following can be reproduced by adding some delay to right after
the ipc is freed in __cifs_put_smb_ses() - which will give
smb2_reconnect_server() worker a chance to run and then accessing
@ses->ipc:
kinit ...
mount.cifs //srv/share /mnt/1 -o sec=krb5,nohandlecache,echo_interval=10
[disconnect srv]
ls /mnt/1 &>/dev/null
sleep 30
kdestroy
[reconnect srv]
sleep 10
umount /mnt/1
...
CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed
CIFS: VFS: \\srv Send error in SessSetup = -126
CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed
CIFS: VFS: \\srv Send error in SessSetup = -126
general protection fault, probably for non-canonical address
0x6b6b6b6b6b6b6b6b: 0000 [#1] PREEMPT SMP NOPTI
CPU: 3 PID: 50 Comm: kworker/3:1 Not tainted 6.9.0-rc2 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-1.fc39
04/01/2014
Workqueue: cifsiod smb2_reconnect_server [cifs]
RIP: 0010:__list_del_entry_valid_or_report+0x33/0xf0
Code: 4f 08 48 85 d2 74 42 48 85 c9 74 59 48 b8 00 01 00 00 00 00 ad
de 48 39 c2 74 61 48 b8 22 01 00 00 00 00 74 69 <48> 8b 01 48 39 f8 75
7b 48 8b 72 08 48 39 c6 0f 85 88 00 00 00 b8
RSP: 0018:ffffc900001bfd70 EFLAGS: 00010a83
RAX: dead000000000122 RBX: ffff88810da53838 RCX: 6b6b6b6b6b6b6b6b
RDX: 6b6b6b6b6b6b6b6b RSI: ffffffffc02f6878 RDI: ffff88810da53800
RBP: ffff88810da53800 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88810c064000
R13: 0000000000000001 R14: ffff88810c064000 R15: ffff8881039cc000
FS: 0000000000000000(0000) GS:ffff888157c00000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe3728b1000 CR3: 000000010caa4000 CR4: 0000000000750ef0
PKRU: 55555554
Call Trace:
<TASK>
? die_addr+0x36/0x90
? exc_general_protection+0x1c1/0x3f0
? asm_exc_general_protection+0x26/0x30
? __list_del_entry_valid_or_report+0x33/0xf0
__cifs_put_smb_ses+0x1ae/0x500 [cifs]
smb2_reconnect_server+0x4ed/0x710 [cifs]
process_one_work+0x205/0x6b0
worker_thread+0x191/0x360
? __pfx_worker_thread+0x10/0x10
kthread+0xe2/0x110
? __pfx_kthread+0x10/0x10
ret_from_fork+0x34/0x50
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
Cc: stable(a)vger.kernel.org
Signed-off-by: Paulo Alcantara (Red Hat) <pc(a)manguebit.com>
Signed-off-by: Steve French <stfrench(a)microsoft.com>
diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c
index 9b85b5341822..ee29bc57300c 100644
--- a/fs/smb/client/connect.c
+++ b/fs/smb/client/connect.c
@@ -232,7 +232,13 @@ cifs_mark_tcp_ses_conns_for_reconnect(struct TCP_Server_Info *server,
spin_lock(&cifs_tcp_ses_lock);
list_for_each_entry_safe(ses, nses, &pserver->smb_ses_list, smb_ses_list) {
- /* check if iface is still active */
+ spin_lock(&ses->ses_lock);
+ if (ses->ses_status == SES_EXITING) {
+ spin_unlock(&ses->ses_lock);
+ continue;
+ }
+ spin_unlock(&ses->ses_lock);
+
spin_lock(&ses->chan_lock);
if (cifs_ses_get_chan_index(ses, server) ==
CIFS_INVAL_CHAN_INDEX) {
@@ -1963,31 +1969,6 @@ cifs_setup_ipc(struct cifs_ses *ses, struct smb3_fs_context *ctx)
return rc;
}
-/**
- * cifs_free_ipc - helper to release the session IPC tcon
- * @ses: smb session to unmount the IPC from
- *
- * Needs to be called everytime a session is destroyed.
- *
- * On session close, the IPC is closed and the server must release all tcons of the session.
- * No need to send a tree disconnect here.
- *
- * Besides, it will make the server to not close durable and resilient files on session close, as
- * specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
- */
-static int
-cifs_free_ipc(struct cifs_ses *ses)
-{
- struct cifs_tcon *tcon = ses->tcon_ipc;
-
- if (tcon == NULL)
- return 0;
-
- tconInfoFree(tcon);
- ses->tcon_ipc = NULL;
- return 0;
-}
-
static struct cifs_ses *
cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
{
@@ -2019,48 +2000,52 @@ cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
void __cifs_put_smb_ses(struct cifs_ses *ses)
{
struct TCP_Server_Info *server = ses->server;
+ struct cifs_tcon *tcon;
unsigned int xid;
size_t i;
+ bool do_logoff;
int rc;
- spin_lock(&ses->ses_lock);
- if (ses->ses_status == SES_EXITING) {
- spin_unlock(&ses->ses_lock);
- return;
- }
- spin_unlock(&ses->ses_lock);
-
- cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
- cifs_dbg(FYI,
- "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->tree_name : "NONE");
-
spin_lock(&cifs_tcp_ses_lock);
- if (--ses->ses_count > 0) {
+ spin_lock(&ses->ses_lock);
+ cifs_dbg(FYI, "%s: id=0x%llx ses_count=%d ses_status=%u ipc=%s\n",
+ __func__, ses->Suid, ses->ses_count, ses->ses_status,
+ ses->tcon_ipc ? ses->tcon_ipc->tree_name : "none");
+ if (ses->ses_status == SES_EXITING || --ses->ses_count > 0) {
+ spin_unlock(&ses->ses_lock);
spin_unlock(&cifs_tcp_ses_lock);
return;
}
- spin_lock(&ses->ses_lock);
- if (ses->ses_status == SES_GOOD)
- ses->ses_status = SES_EXITING;
- spin_unlock(&ses->ses_lock);
- spin_unlock(&cifs_tcp_ses_lock);
-
/* ses_count can never go negative */
WARN_ON(ses->ses_count < 0);
- spin_lock(&ses->ses_lock);
- if (ses->ses_status == SES_EXITING && server->ops->logoff) {
- spin_unlock(&ses->ses_lock);
- cifs_free_ipc(ses);
+ spin_lock(&ses->chan_lock);
+ cifs_chan_clear_need_reconnect(ses, server);
+ spin_unlock(&ses->chan_lock);
+
+ do_logoff = ses->ses_status == SES_GOOD && server->ops->logoff;
+ ses->ses_status = SES_EXITING;
+ tcon = ses->tcon_ipc;
+ ses->tcon_ipc = NULL;
+ spin_unlock(&ses->ses_lock);
+ spin_unlock(&cifs_tcp_ses_lock);
+
+ /*
+ * On session close, the IPC is closed and the server must release all
+ * tcons of the session. No need to send a tree disconnect here.
+ *
+ * Besides, it will make the server to not close durable and resilient
+ * files on session close, as specified in MS-SMB2 3.3.5.6 Receiving an
+ * SMB2 LOGOFF Request.
+ */
+ tconInfoFree(tcon);
+ if (do_logoff) {
xid = get_xid();
rc = server->ops->logoff(xid, ses);
if (rc)
cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
__func__, rc);
_free_xid(xid);
- } else {
- spin_unlock(&ses->ses_lock);
- cifs_free_ipc(ses);
}
spin_lock(&cifs_tcp_ses_lock);
The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 24a9799aa8efecd0eb55a75e35f9d8e6400063aa
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024040837-alkaline-motor-f911@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
24a9799aa8ef ("smb: client: fix UAF in smb2_reconnect_server()")
7257bcf3bdc7 ("cifs: cifs_chan_is_iface_active should be called with chan_lock held")
27e1fd343f80 ("cifs: after disabling multichannel, mark tcon for reconnect")
fa1d0508bdd4 ("cifs: account for primary channel in the interface list")
a6d8fb54a515 ("cifs: distribute channels across interfaces based on speed")
c37ed2d7d098 ("smb: client: remove extra @chan_count check in __cifs_put_smb_ses()")
ff7d80a9f271 ("cifs: fix session state transition to avoid use-after-free issue")
38c8a9a52082 ("smb: move client and server files to common directory fs/smb")
943fb67b0902 ("cifs: missing lock when updating session status")
bc962159e8e3 ("cifs: avoid race conditions with parallel reconnects")
1bcd548d935a ("cifs: prevent data race in cifs_reconnect_tcon()")
e77978de4765 ("cifs: update ip_addr for ses only for primary chan setup")
3c0070f54b31 ("cifs: prevent data race in smb2_reconnect()")
05844bd661d9 ("cifs: print last update time for interface list")
25cf01b7c920 ("cifs: set correct status of tcon ipc when reconnecting")
abdb1742a312 ("cifs: get rid of mount options string parsing")
9fd29a5bae6e ("cifs: use fs_context for automounts")
f391d6ee002e ("cifs: Use after free in debug code")
68e14569d7e5 ("smb3: add dynamic trace points for tree disconnect")
13609a8b3ac6 ("cifs: move from strlcpy with unused retval to strscpy")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 24a9799aa8efecd0eb55a75e35f9d8e6400063aa Mon Sep 17 00:00:00 2001
From: Paulo Alcantara <pc(a)manguebit.com>
Date: Mon, 1 Apr 2024 14:13:10 -0300
Subject: [PATCH] smb: client: fix UAF in smb2_reconnect_server()
The UAF bug is due to smb2_reconnect_server() accessing a session that
is already being teared down by another thread that is executing
__cifs_put_smb_ses(). This can happen when (a) the client has
connection to the server but no session or (b) another thread ends up
setting @ses->ses_status again to something different than
SES_EXITING.
To fix this, we need to make sure to unconditionally set
@ses->ses_status to SES_EXITING and prevent any other threads from
setting a new status while we're still tearing it down.
The following can be reproduced by adding some delay to right after
the ipc is freed in __cifs_put_smb_ses() - which will give
smb2_reconnect_server() worker a chance to run and then accessing
@ses->ipc:
kinit ...
mount.cifs //srv/share /mnt/1 -o sec=krb5,nohandlecache,echo_interval=10
[disconnect srv]
ls /mnt/1 &>/dev/null
sleep 30
kdestroy
[reconnect srv]
sleep 10
umount /mnt/1
...
CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed
CIFS: VFS: \\srv Send error in SessSetup = -126
CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed
CIFS: VFS: \\srv Send error in SessSetup = -126
general protection fault, probably for non-canonical address
0x6b6b6b6b6b6b6b6b: 0000 [#1] PREEMPT SMP NOPTI
CPU: 3 PID: 50 Comm: kworker/3:1 Not tainted 6.9.0-rc2 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-1.fc39
04/01/2014
Workqueue: cifsiod smb2_reconnect_server [cifs]
RIP: 0010:__list_del_entry_valid_or_report+0x33/0xf0
Code: 4f 08 48 85 d2 74 42 48 85 c9 74 59 48 b8 00 01 00 00 00 00 ad
de 48 39 c2 74 61 48 b8 22 01 00 00 00 00 74 69 <48> 8b 01 48 39 f8 75
7b 48 8b 72 08 48 39 c6 0f 85 88 00 00 00 b8
RSP: 0018:ffffc900001bfd70 EFLAGS: 00010a83
RAX: dead000000000122 RBX: ffff88810da53838 RCX: 6b6b6b6b6b6b6b6b
RDX: 6b6b6b6b6b6b6b6b RSI: ffffffffc02f6878 RDI: ffff88810da53800
RBP: ffff88810da53800 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88810c064000
R13: 0000000000000001 R14: ffff88810c064000 R15: ffff8881039cc000
FS: 0000000000000000(0000) GS:ffff888157c00000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe3728b1000 CR3: 000000010caa4000 CR4: 0000000000750ef0
PKRU: 55555554
Call Trace:
<TASK>
? die_addr+0x36/0x90
? exc_general_protection+0x1c1/0x3f0
? asm_exc_general_protection+0x26/0x30
? __list_del_entry_valid_or_report+0x33/0xf0
__cifs_put_smb_ses+0x1ae/0x500 [cifs]
smb2_reconnect_server+0x4ed/0x710 [cifs]
process_one_work+0x205/0x6b0
worker_thread+0x191/0x360
? __pfx_worker_thread+0x10/0x10
kthread+0xe2/0x110
? __pfx_kthread+0x10/0x10
ret_from_fork+0x34/0x50
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
Cc: stable(a)vger.kernel.org
Signed-off-by: Paulo Alcantara (Red Hat) <pc(a)manguebit.com>
Signed-off-by: Steve French <stfrench(a)microsoft.com>
diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c
index 9b85b5341822..ee29bc57300c 100644
--- a/fs/smb/client/connect.c
+++ b/fs/smb/client/connect.c
@@ -232,7 +232,13 @@ cifs_mark_tcp_ses_conns_for_reconnect(struct TCP_Server_Info *server,
spin_lock(&cifs_tcp_ses_lock);
list_for_each_entry_safe(ses, nses, &pserver->smb_ses_list, smb_ses_list) {
- /* check if iface is still active */
+ spin_lock(&ses->ses_lock);
+ if (ses->ses_status == SES_EXITING) {
+ spin_unlock(&ses->ses_lock);
+ continue;
+ }
+ spin_unlock(&ses->ses_lock);
+
spin_lock(&ses->chan_lock);
if (cifs_ses_get_chan_index(ses, server) ==
CIFS_INVAL_CHAN_INDEX) {
@@ -1963,31 +1969,6 @@ cifs_setup_ipc(struct cifs_ses *ses, struct smb3_fs_context *ctx)
return rc;
}
-/**
- * cifs_free_ipc - helper to release the session IPC tcon
- * @ses: smb session to unmount the IPC from
- *
- * Needs to be called everytime a session is destroyed.
- *
- * On session close, the IPC is closed and the server must release all tcons of the session.
- * No need to send a tree disconnect here.
- *
- * Besides, it will make the server to not close durable and resilient files on session close, as
- * specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
- */
-static int
-cifs_free_ipc(struct cifs_ses *ses)
-{
- struct cifs_tcon *tcon = ses->tcon_ipc;
-
- if (tcon == NULL)
- return 0;
-
- tconInfoFree(tcon);
- ses->tcon_ipc = NULL;
- return 0;
-}
-
static struct cifs_ses *
cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
{
@@ -2019,48 +2000,52 @@ cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
void __cifs_put_smb_ses(struct cifs_ses *ses)
{
struct TCP_Server_Info *server = ses->server;
+ struct cifs_tcon *tcon;
unsigned int xid;
size_t i;
+ bool do_logoff;
int rc;
- spin_lock(&ses->ses_lock);
- if (ses->ses_status == SES_EXITING) {
- spin_unlock(&ses->ses_lock);
- return;
- }
- spin_unlock(&ses->ses_lock);
-
- cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
- cifs_dbg(FYI,
- "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->tree_name : "NONE");
-
spin_lock(&cifs_tcp_ses_lock);
- if (--ses->ses_count > 0) {
+ spin_lock(&ses->ses_lock);
+ cifs_dbg(FYI, "%s: id=0x%llx ses_count=%d ses_status=%u ipc=%s\n",
+ __func__, ses->Suid, ses->ses_count, ses->ses_status,
+ ses->tcon_ipc ? ses->tcon_ipc->tree_name : "none");
+ if (ses->ses_status == SES_EXITING || --ses->ses_count > 0) {
+ spin_unlock(&ses->ses_lock);
spin_unlock(&cifs_tcp_ses_lock);
return;
}
- spin_lock(&ses->ses_lock);
- if (ses->ses_status == SES_GOOD)
- ses->ses_status = SES_EXITING;
- spin_unlock(&ses->ses_lock);
- spin_unlock(&cifs_tcp_ses_lock);
-
/* ses_count can never go negative */
WARN_ON(ses->ses_count < 0);
- spin_lock(&ses->ses_lock);
- if (ses->ses_status == SES_EXITING && server->ops->logoff) {
- spin_unlock(&ses->ses_lock);
- cifs_free_ipc(ses);
+ spin_lock(&ses->chan_lock);
+ cifs_chan_clear_need_reconnect(ses, server);
+ spin_unlock(&ses->chan_lock);
+
+ do_logoff = ses->ses_status == SES_GOOD && server->ops->logoff;
+ ses->ses_status = SES_EXITING;
+ tcon = ses->tcon_ipc;
+ ses->tcon_ipc = NULL;
+ spin_unlock(&ses->ses_lock);
+ spin_unlock(&cifs_tcp_ses_lock);
+
+ /*
+ * On session close, the IPC is closed and the server must release all
+ * tcons of the session. No need to send a tree disconnect here.
+ *
+ * Besides, it will make the server to not close durable and resilient
+ * files on session close, as specified in MS-SMB2 3.3.5.6 Receiving an
+ * SMB2 LOGOFF Request.
+ */
+ tconInfoFree(tcon);
+ if (do_logoff) {
xid = get_xid();
rc = server->ops->logoff(xid, ses);
if (rc)
cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
__func__, rc);
_free_xid(xid);
- } else {
- spin_unlock(&ses->ses_lock);
- cifs_free_ipc(ses);
}
spin_lock(&cifs_tcp_ses_lock);
The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 24a9799aa8efecd0eb55a75e35f9d8e6400063aa
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024040832-episode-phrasing-9e1a@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
24a9799aa8ef ("smb: client: fix UAF in smb2_reconnect_server()")
7257bcf3bdc7 ("cifs: cifs_chan_is_iface_active should be called with chan_lock held")
27e1fd343f80 ("cifs: after disabling multichannel, mark tcon for reconnect")
fa1d0508bdd4 ("cifs: account for primary channel in the interface list")
a6d8fb54a515 ("cifs: distribute channels across interfaces based on speed")
c37ed2d7d098 ("smb: client: remove extra @chan_count check in __cifs_put_smb_ses()")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 24a9799aa8efecd0eb55a75e35f9d8e6400063aa Mon Sep 17 00:00:00 2001
From: Paulo Alcantara <pc(a)manguebit.com>
Date: Mon, 1 Apr 2024 14:13:10 -0300
Subject: [PATCH] smb: client: fix UAF in smb2_reconnect_server()
The UAF bug is due to smb2_reconnect_server() accessing a session that
is already being teared down by another thread that is executing
__cifs_put_smb_ses(). This can happen when (a) the client has
connection to the server but no session or (b) another thread ends up
setting @ses->ses_status again to something different than
SES_EXITING.
To fix this, we need to make sure to unconditionally set
@ses->ses_status to SES_EXITING and prevent any other threads from
setting a new status while we're still tearing it down.
The following can be reproduced by adding some delay to right after
the ipc is freed in __cifs_put_smb_ses() - which will give
smb2_reconnect_server() worker a chance to run and then accessing
@ses->ipc:
kinit ...
mount.cifs //srv/share /mnt/1 -o sec=krb5,nohandlecache,echo_interval=10
[disconnect srv]
ls /mnt/1 &>/dev/null
sleep 30
kdestroy
[reconnect srv]
sleep 10
umount /mnt/1
...
CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed
CIFS: VFS: \\srv Send error in SessSetup = -126
CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed
CIFS: VFS: \\srv Send error in SessSetup = -126
general protection fault, probably for non-canonical address
0x6b6b6b6b6b6b6b6b: 0000 [#1] PREEMPT SMP NOPTI
CPU: 3 PID: 50 Comm: kworker/3:1 Not tainted 6.9.0-rc2 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-1.fc39
04/01/2014
Workqueue: cifsiod smb2_reconnect_server [cifs]
RIP: 0010:__list_del_entry_valid_or_report+0x33/0xf0
Code: 4f 08 48 85 d2 74 42 48 85 c9 74 59 48 b8 00 01 00 00 00 00 ad
de 48 39 c2 74 61 48 b8 22 01 00 00 00 00 74 69 <48> 8b 01 48 39 f8 75
7b 48 8b 72 08 48 39 c6 0f 85 88 00 00 00 b8
RSP: 0018:ffffc900001bfd70 EFLAGS: 00010a83
RAX: dead000000000122 RBX: ffff88810da53838 RCX: 6b6b6b6b6b6b6b6b
RDX: 6b6b6b6b6b6b6b6b RSI: ffffffffc02f6878 RDI: ffff88810da53800
RBP: ffff88810da53800 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88810c064000
R13: 0000000000000001 R14: ffff88810c064000 R15: ffff8881039cc000
FS: 0000000000000000(0000) GS:ffff888157c00000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe3728b1000 CR3: 000000010caa4000 CR4: 0000000000750ef0
PKRU: 55555554
Call Trace:
<TASK>
? die_addr+0x36/0x90
? exc_general_protection+0x1c1/0x3f0
? asm_exc_general_protection+0x26/0x30
? __list_del_entry_valid_or_report+0x33/0xf0
__cifs_put_smb_ses+0x1ae/0x500 [cifs]
smb2_reconnect_server+0x4ed/0x710 [cifs]
process_one_work+0x205/0x6b0
worker_thread+0x191/0x360
? __pfx_worker_thread+0x10/0x10
kthread+0xe2/0x110
? __pfx_kthread+0x10/0x10
ret_from_fork+0x34/0x50
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
Cc: stable(a)vger.kernel.org
Signed-off-by: Paulo Alcantara (Red Hat) <pc(a)manguebit.com>
Signed-off-by: Steve French <stfrench(a)microsoft.com>
diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c
index 9b85b5341822..ee29bc57300c 100644
--- a/fs/smb/client/connect.c
+++ b/fs/smb/client/connect.c
@@ -232,7 +232,13 @@ cifs_mark_tcp_ses_conns_for_reconnect(struct TCP_Server_Info *server,
spin_lock(&cifs_tcp_ses_lock);
list_for_each_entry_safe(ses, nses, &pserver->smb_ses_list, smb_ses_list) {
- /* check if iface is still active */
+ spin_lock(&ses->ses_lock);
+ if (ses->ses_status == SES_EXITING) {
+ spin_unlock(&ses->ses_lock);
+ continue;
+ }
+ spin_unlock(&ses->ses_lock);
+
spin_lock(&ses->chan_lock);
if (cifs_ses_get_chan_index(ses, server) ==
CIFS_INVAL_CHAN_INDEX) {
@@ -1963,31 +1969,6 @@ cifs_setup_ipc(struct cifs_ses *ses, struct smb3_fs_context *ctx)
return rc;
}
-/**
- * cifs_free_ipc - helper to release the session IPC tcon
- * @ses: smb session to unmount the IPC from
- *
- * Needs to be called everytime a session is destroyed.
- *
- * On session close, the IPC is closed and the server must release all tcons of the session.
- * No need to send a tree disconnect here.
- *
- * Besides, it will make the server to not close durable and resilient files on session close, as
- * specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
- */
-static int
-cifs_free_ipc(struct cifs_ses *ses)
-{
- struct cifs_tcon *tcon = ses->tcon_ipc;
-
- if (tcon == NULL)
- return 0;
-
- tconInfoFree(tcon);
- ses->tcon_ipc = NULL;
- return 0;
-}
-
static struct cifs_ses *
cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
{
@@ -2019,48 +2000,52 @@ cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
void __cifs_put_smb_ses(struct cifs_ses *ses)
{
struct TCP_Server_Info *server = ses->server;
+ struct cifs_tcon *tcon;
unsigned int xid;
size_t i;
+ bool do_logoff;
int rc;
- spin_lock(&ses->ses_lock);
- if (ses->ses_status == SES_EXITING) {
- spin_unlock(&ses->ses_lock);
- return;
- }
- spin_unlock(&ses->ses_lock);
-
- cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
- cifs_dbg(FYI,
- "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->tree_name : "NONE");
-
spin_lock(&cifs_tcp_ses_lock);
- if (--ses->ses_count > 0) {
+ spin_lock(&ses->ses_lock);
+ cifs_dbg(FYI, "%s: id=0x%llx ses_count=%d ses_status=%u ipc=%s\n",
+ __func__, ses->Suid, ses->ses_count, ses->ses_status,
+ ses->tcon_ipc ? ses->tcon_ipc->tree_name : "none");
+ if (ses->ses_status == SES_EXITING || --ses->ses_count > 0) {
+ spin_unlock(&ses->ses_lock);
spin_unlock(&cifs_tcp_ses_lock);
return;
}
- spin_lock(&ses->ses_lock);
- if (ses->ses_status == SES_GOOD)
- ses->ses_status = SES_EXITING;
- spin_unlock(&ses->ses_lock);
- spin_unlock(&cifs_tcp_ses_lock);
-
/* ses_count can never go negative */
WARN_ON(ses->ses_count < 0);
- spin_lock(&ses->ses_lock);
- if (ses->ses_status == SES_EXITING && server->ops->logoff) {
- spin_unlock(&ses->ses_lock);
- cifs_free_ipc(ses);
+ spin_lock(&ses->chan_lock);
+ cifs_chan_clear_need_reconnect(ses, server);
+ spin_unlock(&ses->chan_lock);
+
+ do_logoff = ses->ses_status == SES_GOOD && server->ops->logoff;
+ ses->ses_status = SES_EXITING;
+ tcon = ses->tcon_ipc;
+ ses->tcon_ipc = NULL;
+ spin_unlock(&ses->ses_lock);
+ spin_unlock(&cifs_tcp_ses_lock);
+
+ /*
+ * On session close, the IPC is closed and the server must release all
+ * tcons of the session. No need to send a tree disconnect here.
+ *
+ * Besides, it will make the server to not close durable and resilient
+ * files on session close, as specified in MS-SMB2 3.3.5.6 Receiving an
+ * SMB2 LOGOFF Request.
+ */
+ tconInfoFree(tcon);
+ if (do_logoff) {
xid = get_xid();
rc = server->ops->logoff(xid, ses);
if (rc)
cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
__func__, rc);
_free_xid(xid);
- } else {
- spin_unlock(&ses->ses_lock);
- cifs_free_ipc(ses);
}
spin_lock(&cifs_tcp_ses_lock);