Linux: >> Linux Kernel >> 3.10.27 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
vhost-scsi: Fix handling of multiple calls to vhost_scsi_set_endpoint
If vhost_scsi_set_endpoint is called multiple times without a
vhost_scsi_clear_endpoint between them, we can hit multiple bugs
found by Haoran Zhang:
1. Use-after-free when no tpgs are found:
This fixes a use after free that occurs when vhost_scsi_set_endpoint is
called more than once and calls after the first call do not find any
tpgs to add to the vs_tpg. When vhost_scsi_set_endpoint first finds
tpgs to add to the vs_tpg array match=true, so we will do:
vhost_vq_set_backend(vq, vs_tpg);
...
kfree(vs->vs_tpg);
vs->vs_tpg = vs_tpg;
If vhost_scsi_set_endpoint is called again and no tpgs are found
match=false so we skip the vhost_vq_set_backend call leaving the
pointer to the vs_tpg we then free via:
kfree(vs->vs_tpg);
vs->vs_tpg = vs_tpg;
If a scsi request is then sent we do:
vhost_scsi_handle_vq -> vhost_scsi_get_req -> vhost_vq_get_backend
which sees the vs_tpg we just did a kfree on.
2. Tpg dir removal hang:
This patch fixes an issue where we cannot remove a LIO/target layer
tpg (and structs above it like the target) dir due to the refcount
dropping to -1.
The problem is that if vhost_scsi_set_endpoint detects a tpg is already
in the vs->vs_tpg array or if the tpg has been removed so
target_depend_item fails, the undepend goto handler will do
target_undepend_item on all tpgs in the vs_tpg array dropping their
refcount to 0. At this time vs_tpg contains both the tpgs we have added
in the current vhost_scsi_set_endpoint call as well as tpgs we added in
previous calls which are also in vs->vs_tpg.
Later, when vhost_scsi_clear_endpoint runs it will do
target_undepend_item on all the tpgs in the vs->vs_tpg which will drop
their refcount to -1. Userspace will then not be able to remove the tpg
and will hang when it tries to do rmdir on the tpg dir.
3. Tpg leak:
This fixes a bug where we can leak tpgs and cause them to be
un-removable because the target name is overwritten when
vhost_scsi_set_endpoint is called multiple times but with different
target names.
The bug occurs if a user has called VHOST_SCSI_SET_ENDPOINT and setup
a vhost-scsi device to target/tpg mapping, then calls
VHOST_SCSI_SET_ENDPOINT again with a new target name that has tpgs we
haven't seen before (target1 has tpg1 but target2 has tpg2). When this
happens we don't teardown the old target tpg mapping and just overwrite
the target name and the vs->vs_tpg array. Later when we do
vhost_scsi_clear_endpoint, we are passed in either target1 or target2's
name and we will only match that target's tpgs when we loop over the
vs->vs_tpg. We will then return from the function without doing
target_undepend_item on the tpgs.
Because of all these bugs, it looks like being able to call
vhost_scsi_set_endpoint multiple times was never supported. The major
user, QEMU, already has checks to prevent this use case. So to fix the
issues, this patch prevents vhost_scsi_set_endpoint from being called
if it's already successfully added tpgs. To add, remove or change the
tpg config or target name, you must do a vhost_scsi_clear_endpoint
first.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
spufs: fix a leak in spufs_create_context()
Leak fixes back in 2008 missed one case - if we are trying to set affinity
and spufs_mkdir() fails, we need to drop the reference to neighbor.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
spufs: fix gang directory lifetimes
prior to "[POWERPC] spufs: Fix gang destroy leaks" we used to have
a problem with gang lifetimes - creation of a gang returns opened
gang directory, which normally gets removed when that gets closed,
but if somebody has created a context belonging to that gang and
kept it alive until the gang got closed, removal failed and we
ended up with a leak.
Unfortunately, it had been fixed the wrong way. Dentry of gang
directory was no longer pinned, and rmdir on close was gone.
One problem was that failure of open kept calling simple_rmdir()
as cleanup, which meant an unbalanced dput(). Another bug was
in the success case - gang creation incremented link count on
root directory, but that was no longer undone when gang got
destroyed.
Fix consists of
* reverting the commit in question
* adding a counter to gang, protected by ->i_rwsem
of gang directory inode.
* having it set to 1 at creation time, dropped
in both spufs_dir_close() and spufs_gang_close() and bumped
in spufs_create_context(), provided that it's not 0.
* using simple_recursive_removal() to take the gang
directory out when counter reaches zero.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
spufs: fix a leak on spufs_new_file() failure
It's called from spufs_fill_dir(), and caller of that will do
spufs_rmdir() in case of failure. That does remove everything
we'd managed to create, but... the problem dentry is still
negative. IOW, it needs to be explicitly dropped.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
net: ibmveth: make veth_pool_store stop hanging
v2:
- Created a single error handling unlock and exit in veth_pool_store
- Greatly expanded commit message with previous explanatory-only text
Summary: Use rtnl_mutex to synchronize veth_pool_store with itself,
ibmveth_close and ibmveth_open, preventing multiple calls in a row to
napi_disable.
Background: Two (or more) threads could call veth_pool_store through
writing to /sys/devices/vio/30000002/pool*/*. You can do this easily
with a little shell script. This causes a hang.
I configured LOCKDEP, compiled ibmveth.c with DEBUG, and built a new
kernel. I ran this test again and saw:
Setting pool0/active to 0
Setting pool1/active to 1
[ 73.911067][ T4365] ibmveth 30000002 eth0: close starting
Setting pool1/active to 1
Setting pool1/active to 0
[ 73.911367][ T4366] ibmveth 30000002 eth0: close starting
[ 73.916056][ T4365] ibmveth 30000002 eth0: close complete
[ 73.916064][ T4365] ibmveth 30000002 eth0: open starting
[ 110.808564][ T712] systemd-journald[712]: Sent WATCHDOG=1 notification.
[ 230.808495][ T712] systemd-journald[712]: Sent WATCHDOG=1 notification.
[ 243.683786][ T123] INFO: task stress.sh:4365 blocked for more than 122 seconds.
[ 243.683827][ T123] Not tainted 6.14.0-01103-g2df0c02dab82-dirty #8
[ 243.683833][ T123] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 243.683838][ T123] task:stress.sh state:D stack:28096 pid:4365 tgid:4365 ppid:4364 task_flags:0x400040 flags:0x00042000
[ 243.683852][ T123] Call Trace:
[ 243.683857][ T123] [c00000000c38f690] [0000000000000001] 0x1 (unreliable)
[ 243.683868][ T123] [c00000000c38f840] [c00000000001f908] __switch_to+0x318/0x4e0
[ 243.683878][ T123] [c00000000c38f8a0] [c000000001549a70] __schedule+0x500/0x12a0
[ 243.683888][ T123] [c00000000c38f9a0] [c00000000154a878] schedule+0x68/0x210
[ 243.683896][ T123] [c00000000c38f9d0] [c00000000154ac80] schedule_preempt_disabled+0x30/0x50
[ 243.683904][ T123] [c00000000c38fa00] [c00000000154dbb0] __mutex_lock+0x730/0x10f0
[ 243.683913][ T123] [c00000000c38fb10] [c000000001154d40] napi_enable+0x30/0x60
[ 243.683921][ T123] [c00000000c38fb40] [c000000000f4ae94] ibmveth_open+0x68/0x5dc
[ 243.683928][ T123] [c00000000c38fbe0] [c000000000f4aa20] veth_pool_store+0x220/0x270
[ 243.683936][ T123] [c00000000c38fc70] [c000000000826278] sysfs_kf_write+0x68/0xb0
[ 243.683944][ T123] [c00000000c38fcb0] [c0000000008240b8] kernfs_fop_write_iter+0x198/0x2d0
[ 243.683951][ T123] [c00000000c38fd00] [c00000000071b9ac] vfs_write+0x34c/0x650
[ 243.683958][ T123] [c00000000c38fdc0] [c00000000071bea8] ksys_write+0x88/0x150
[ 243.683966][ T123] [c00000000c38fe10] [c0000000000317f4] system_call_exception+0x124/0x340
[ 243.683973][ T123] [c00000000c38fe50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec
...
[ 243.684087][ T123] Showing all locks held in the system:
[ 243.684095][ T123] 1 lock held by khungtaskd/123:
[ 243.684099][ T123] #0: c00000000278e370 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x50/0x248
[ 243.684114][ T123] 4 locks held by stress.sh/4365:
[ 243.684119][ T123] #0: c00000003a4cd3f8 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x88/0x150
[ 243.684132][ T123] #1: c000000041aea888 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x154/0x2d0
[ 243.684143][ T123] #2: c0000000366fb9a8 (kn->active#64){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x160/0x2d0
[ 243.684155][ T123] #3: c000000035ff4cb8 (&dev->lock){+.+.}-{3:3}, at: napi_enable+0x30/0x60
[ 243.684166][ T123] 5 locks held by stress.sh/4366:
[ 243.684170][ T123] #0: c00000003a4cd3f8 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x88/0x150
[ 243.
---truncated---
CVSS Score
5.5
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix null pointer dereference in alloc_preauth_hash()
The Client send malformed smb2 negotiate request. ksmbd return error
response. Subsequently, the client can send smb2 session setup even
thought conn->preauth_info is not allocated.
This patch add KSMBD_SESS_NEED_SETUP status of connection to ignore
session setup request if smb2 negotiate phase is not complete.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: validate zero num_subauth before sub_auth is accessed
Access psid->sub_auth[psid->num_subauth - 1] without checking
if num_subauth is non-zero leads to an out-of-bounds read.
This patch adds a validation step to ensure num_subauth != 0
before sub_auth is accessed.
CVSS Score
7.1
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix session use-after-free in multichannel connection
There is a race condition between session setup and
ksmbd_sessions_deregister. The session can be freed before the connection
is added to channel list of session.
This patch check reference count of session before freeing it.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix use-after-free in ksmbd_sessions_deregister()
In multichannel mode, UAF issue can occur in session_deregister
when the second channel sets up a session through the connection of
the first channel. session that is freed through the global session
table can be accessed again through ->sessions of connection.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
nfsd: put dl_stid if fail to queue dl_recall
Before calling nfsd4_run_cb to queue dl_recall to the callback_wq, we
increment the reference count of dl_stid.
We expect that after the corresponding work_struct is processed, the
reference count of dl_stid will be decremented through the callback
function nfsd4_cb_recall_release.
However, if the call to nfsd4_run_cb fails, the incremented reference
count of dl_stid will not be decremented correspondingly, leading to the
following nfs4_stid leak:
unreferenced object 0xffff88812067b578 (size 344):
comm "nfsd", pid 2761, jiffies 4295044002 (age 5541.241s)
hex dump (first 32 bytes):
01 00 00 00 6b 6b 6b 6b b8 02 c0 e2 81 88 ff ff ....kkkk........
00 6b 6b 6b 6b 6b 6b 6b 00 00 00 00 ad 4e ad de .kkkkkkk.....N..
backtrace:
kmem_cache_alloc+0x4b9/0x700
nfsd4_process_open1+0x34/0x300
nfsd4_open+0x2d1/0x9d0
nfsd4_proc_compound+0x7a2/0xe30
nfsd_dispatch+0x241/0x3e0
svc_process_common+0x5d3/0xcc0
svc_process+0x2a3/0x320
nfsd+0x180/0x2e0
kthread+0x199/0x1d0
ret_from_fork+0x30/0x50
ret_from_fork_asm+0x1b/0x30
unreferenced object 0xffff8881499f4d28 (size 368):
comm "nfsd", pid 2761, jiffies 4295044005 (age 5541.239s)
hex dump (first 32 bytes):
01 00 00 00 00 00 00 00 30 4d 9f 49 81 88 ff ff ........0M.I....
30 4d 9f 49 81 88 ff ff 20 00 00 00 01 00 00 00 0M.I.... .......
backtrace:
kmem_cache_alloc+0x4b9/0x700
nfs4_alloc_stid+0x29/0x210
alloc_init_deleg+0x92/0x2e0
nfs4_set_delegation+0x284/0xc00
nfs4_open_delegation+0x216/0x3f0
nfsd4_process_open2+0x2b3/0xee0
nfsd4_open+0x770/0x9d0
nfsd4_proc_compound+0x7a2/0xe30
nfsd_dispatch+0x241/0x3e0
svc_process_common+0x5d3/0xcc0
svc_process+0x2a3/0x320
nfsd+0x180/0x2e0
kthread+0x199/0x1d0
ret_from_fork+0x30/0x50
ret_from_fork_asm+0x1b/0x30
Fix it by checking the result of nfsd4_run_cb and call nfs4_put_stid if
fail to queue dl_recall.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-04-16