af_unix: fix struct pid leaks in OOB support
syzbot reported struct pid leak [1].
Issue is that queue_oob() calls maybe_add_creds() which potentially
holds a reference on a pid.
But skb->destructor is not set (either directly or by calling
unix_scm_to_skb())
This means that subsequent kfree_skb() or consume_skb() would leak
this reference.
In this fix, I chose to fully support scm even for the OOB message.
[1]
BUG: memory leak
unreferenced object 0xffff8881053e7f80 (size 128):
comm "syz-executor242", pid 5066, jiffies 4294946079 (age 13.220s)
hex dump (first 32 bytes):
01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff812ae26a>] alloc_pid+0x6a/0x560 kernel/pid.c:180
[<ffffffff812718df>] copy_process+0x169f/0x26c0 kernel/fork.c:2285
[<ffffffff81272b37>] kernel_clone+0xf7/0x610 kernel/fork.c:2684
[<ffffffff812730cc>] __do_sys_clone+0x7c/0xb0 kernel/fork.c:2825
[<ffffffff849ad699>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff849ad699>] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
[<ffffffff84a0008b>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
Metrics
Affected Vendors & Products
| Source | ID | Title |
|---|---|---|
EUVD |
EUVD-2025-13114 | In the Linux kernel, the following vulnerability has been resolved: af_unix: fix struct pid leaks in OOB support syzbot reported struct pid leak [1]. Issue is that queue_oob() calls maybe_add_creds() which potentially holds a reference on a pid. But skb->destructor is not set (either directly or by calling unix_scm_to_skb()) This means that subsequent kfree_skb() or consume_skb() would leak this reference. In this fix, I chose to fully support scm even for the OOB message. [1] BUG: memory leak unreferenced object 0xffff8881053e7f80 (size 128): comm "syz-executor242", pid 5066, jiffies 4294946079 (age 13.220s) hex dump (first 32 bytes): 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff812ae26a>] alloc_pid+0x6a/0x560 kernel/pid.c:180 [<ffffffff812718df>] copy_process+0x169f/0x26c0 kernel/fork.c:2285 [<ffffffff81272b37>] kernel_clone+0xf7/0x610 kernel/fork.c:2684 [<ffffffff812730cc>] __do_sys_clone+0x7c/0xb0 kernel/fork.c:2825 [<ffffffff849ad699>] do_syscall_x64 arch/x86/entry/common.c:50 [inline] [<ffffffff849ad699>] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 [<ffffffff84a0008b>] entry_SYSCALL_64_after_hwframe+0x63/0xcd |
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
Mon, 10 Nov 2025 17:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-125 | |
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.3:rc1:*:*:*:*:*:* |
|
| Metrics |
cvssV3_1
|
cvssV3_1
|
Thu, 10 Jul 2025 03:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
cvssV3_1
|
cvssV3_1
|
Sat, 07 Jun 2025 03:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
cvssV3_1
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cvssV3_1
|
Mon, 05 May 2025 14:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
| |
| Metrics |
threat_severity
|
cvssV3_1
|
Fri, 02 May 2025 16:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: af_unix: fix struct pid leaks in OOB support syzbot reported struct pid leak [1]. Issue is that queue_oob() calls maybe_add_creds() which potentially holds a reference on a pid. But skb->destructor is not set (either directly or by calling unix_scm_to_skb()) This means that subsequent kfree_skb() or consume_skb() would leak this reference. In this fix, I chose to fully support scm even for the OOB message. [1] BUG: memory leak unreferenced object 0xffff8881053e7f80 (size 128): comm "syz-executor242", pid 5066, jiffies 4294946079 (age 13.220s) hex dump (first 32 bytes): 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff812ae26a>] alloc_pid+0x6a/0x560 kernel/pid.c:180 [<ffffffff812718df>] copy_process+0x169f/0x26c0 kernel/fork.c:2285 [<ffffffff81272b37>] kernel_clone+0xf7/0x610 kernel/fork.c:2684 [<ffffffff812730cc>] __do_sys_clone+0x7c/0xb0 kernel/fork.c:2825 [<ffffffff849ad699>] do_syscall_x64 arch/x86/entry/common.c:50 [inline] [<ffffffff849ad699>] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 [<ffffffff84a0008b>] entry_SYSCALL_64_after_hwframe+0x63/0xcd | |
| Title | af_unix: fix struct pid leaks in OOB support | |
| References |
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2025-05-04T07:50:40.659Z
Reserved: 2025-05-02T15:51:43.561Z
Link: CVE-2023-53136
No data.
Status : Analyzed
Published: 2025-05-02T16:15:32.540
Modified: 2025-11-10T17:39:17.243
Link: CVE-2023-53136
OpenCVE Enrichment
Updated: 2025-06-24T09:51:39Z
EUVD