In the Linux kernel, the following vulnerability has been resolved:
net: fix use-after-free in tw_timer_handler
A real world panic issue was found as follow in Linux 5.4.
BUG: unable to handle page fault for address: ffffde49a863de28
PGD 7e6fe62067 P4D 7e6fe62067 PUD 7e6fe63067 PMD f51e064067 PTE 0
RIP: 0010:tw_timer_handler+0x20/0x40
Call Trace:
<IRQ>
call_timer_fn+0x2b/0x120
run_timer_softirq+0x1ef/0x450
__do_softirq+0x10d/0x2b8
irq_exit+0xc7/0xd0
smp_apic_timer_interrupt+0x68/0x120
apic_timer_interrupt+0xf/0x20
This issue was also reported since 2017 in the thread [1],
unfortunately, the issue was still can be reproduced after fixing
DCCP.
The ipv4_mib_exit_net is called before tcp_sk_exit_batch when a net
namespace is destroyed since tcp_sk_ops is registered befrore
ipv4_mib_ops, which means tcp_sk_ops is in the front of ipv4_mib_ops
in the list of pernet_list. There will be a use-after-free on
net->mib.net_statistics in tw_timer_handler after ipv4_mib_exit_net
if there are some inflight time-wait timers.
This bug is not introduced by commit f2bf415cfed7 ("mib: add net to
NET_ADD_STATS_BH") since the net_statistics is a global variable
instead of dynamic allocation and freeing. Actually, commit
61a7e26028b9 ("mib: put net statistics on struct net") introduces
the bug since it put net statistics on struct net and free it when
net namespace is destroyed.
Moving init_ipv4_mibs() to the front of tcp_init() to fix this bug
and replace pr_crit() with panic() since continuing is meaningless
when init_ipv4_mibs() fails.
[1] https://groups.google.com/g/syzkaller/c/p1tn-_Kc6l4/m/smuL_FMAAgAJ?pli=1
References
Configurations
Configuration 1 (hide)
|
History
21 Nov 2024, 06:34
| Type | Values Removed | Values Added |
|---|---|---|
| References | () https://git.kernel.org/stable/c/08eacbd141e2495d2fcdde84358a06c4f95cbb13 - Patch | |
| References | () https://git.kernel.org/stable/c/15579e1301f856ad9385d720c9267c11032a5022 - Patch | |
| References | () https://git.kernel.org/stable/c/2386e81a1d277f540e1285565c9d41d531bb69d4 - Patch | |
| References | () https://git.kernel.org/stable/c/5c2fe20ad37ff56070ae0acb34152333976929b4 - Patch | |
| References | () https://git.kernel.org/stable/c/a8e1944b44f94f5c5f530e434c5eaee787254566 - Patch | |
| References | () https://git.kernel.org/stable/c/e22e45fc9e41bf9fcc1e92cfb78eb92786728ef0 - Patch | |
| References | () https://git.kernel.org/stable/c/e73164e89d1be561228a4534e1091369ee4ba41a - Patch | |
| References | () https://git.kernel.org/stable/c/fe5838c22b986c1190f1dce9aa09bf6a491c1a69 - Patch |
10 Apr 2024, 19:20
| Type | Values Removed | Values Added |
|---|---|---|
| CPE | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| CWE | CWE-416 | |
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 7.8 |
| First Time |
Linux
Linux linux Kernel |
|
| References | () https://git.kernel.org/stable/c/08eacbd141e2495d2fcdde84358a06c4f95cbb13 - Patch | |
| References | () https://git.kernel.org/stable/c/15579e1301f856ad9385d720c9267c11032a5022 - Patch | |
| References | () https://git.kernel.org/stable/c/2386e81a1d277f540e1285565c9d41d531bb69d4 - Patch | |
| References | () https://git.kernel.org/stable/c/5c2fe20ad37ff56070ae0acb34152333976929b4 - Patch | |
| References | () https://git.kernel.org/stable/c/a8e1944b44f94f5c5f530e434c5eaee787254566 - Patch | |
| References | () https://git.kernel.org/stable/c/e22e45fc9e41bf9fcc1e92cfb78eb92786728ef0 - Patch | |
| References | () https://git.kernel.org/stable/c/e73164e89d1be561228a4534e1091369ee4ba41a - Patch | |
| References | () https://git.kernel.org/stable/c/fe5838c22b986c1190f1dce9aa09bf6a491c1a69 - Patch |
27 Feb 2024, 14:19
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2024-02-27 10:15
Updated : 2024-11-21 06:34
NVD link : CVE-2021-46936
Mitre link : CVE-2021-46936
CVE.ORG link : CVE-2021-46936
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-416
Use After Free