CVE-2021-47408
published 2024-05-21CVE-2021-47408: In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: serialize hash resizes and cleanups Syzbot was able to trigger the…
PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.25%
16.7th percentile
In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: serialize hash resizes and cleanups
Syzbot was able to trigger the following warning [1]
No repro found by syzbot yet but I was able to trigger similar issue
by having 2 scripts running in parallel, changing conntrack hash sizes,
and:
for j in `seq 1 1000` ; do unshare -n /bin/true >/dev/null ; done
It would take more than 5 minutes for net_namespace structures
to be cleaned up.
This is because nf_ct_iterate_cleanup() has to restart everytime
a resize happened.
By adding a mutex, we can serialize hash resizes and cleanups
and also make get_next_corpse() faster by skipping over empty
buckets.
Even without resizes in the picture, this patch considerably
speeds up network namespace dismantles.
[1]
INFO: task syz-executor.0:8312 can't die for more than 144 seconds.
task:syz-executor.0 state:R running task stack:25672 pid: 8312 ppid: 6573 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:4955 [inline]
__schedule+0x940/0x26f0 kernel/sched/core.c:6236
preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6408
preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35
__local_bh_enable_ip+0x109/0x120 kernel/softirq.c:390
local_bh_enable include/linux/bottom_half.h:32 [inline]
get_next_corpse net/netfilter/nf_conntrack_core.c:2252 [inline]
nf_ct_iterate_cleanup+0x15a/0x450 net/netfilter/nf_conntrack_core.c:2275
nf_conntrack_cleanup_net_list+0x14c/0x4f0 net/netfilter/nf_conntrack_core.c:2469
ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171
setup_net+0x639/0xa30 net/core/net_namespace.c:349
copy_net_ns+0x319/0x760 net/core/net_namespace.c:470
create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226
ksys_unshare+0x445/0x920 kernel/fork.c:3128
__do_sys_unshare kernel/fork.c:3202 [inline]
__se_sys_unshare kernel/fork.c:3200 [inline]
__x64_sys_unshare+0x2d/0x40 kernel/fork.c:3200
do_syscall_x64 arch/x86/e
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 5.14.12-1 (bookworm) | linux 5.14.12-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 0d02d5646eb84403766a11a1d3b19e670a3d45d5 < e2d192301a0df8160d1555b66ae8611e8050e424 | e2d192301a0df8160d1555b66ae8611e8050e424 |
| linux | linux | >= 0d02d5646eb84403766a11a1d3b19e670a3d45d5 < 7ea6f5848281182ce0cff6cafdcf3fbdeb8ca7e1 | 7ea6f5848281182ce0cff6cafdcf3fbdeb8ca7e1 |
| linux | linux | >= 0d02d5646eb84403766a11a1d3b19e670a3d45d5 < e9edc188fc76499b0b9bd60364084037f6d03773 | e9edc188fc76499b0b9bd60364084037f6d03773 |
| linux | linux_kernel | < 5.10.71 | 5.10.71 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 5.10.84-1 | 5.10.84-1 |
| linux | linux_kernel | >= 0 < 5.14.12-1 | 5.14.12-1 |
| linux | linux_kernel | >= 0 < 5.14.12-1 | 5.14.12-1 |
| linux | linux_kernel | >= 0 < 5.14.12-1 | 5.14.12-1 |
| linux | linux_kernel | >= 5.11 < 5.14.10 | 5.14.10 |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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OSV
CVE-2021-47408: In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: serialize hash resizes and cleanups Syzbot was able to trigg
osv·2024-05-21·CVSS 5.5
CVE-2021-47408 [MEDIUM] CVE-2021-47408: In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: serialize hash resizes and cleanups Syzbot was able to trigg
In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: serialize hash resizes and cleanups Syzbot was able to trigger the following warning [1] No repro found by syzbot yet but I was able to trigger similar issue by having 2 scripts running in parallel, changing conntrack hash sizes, and: for j in `seq 1 1000` ; do unshare -n /bin/true >/dev/null ; done It would take more than 5 minutes for net_namespace structures to be cleaned up. This is because nf_ct_iterate_cleanup() has to restart everytime a resize happened. By adding a mutex, we can serialize hash resizes and cleanups and also make get_next_corpse() faster by skipping over empty buckets. Even without resizes in the picture, this patch considerably speeds up network namespace dismantles. [1] INFO:
GHSA
GHSA-4gxv-hggr-2473: In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: serialize hash resizes and cleanups
Syzbot was able to tri
ghsa_unreviewed·2024-05-21
CVE-2021-47408 [MEDIUM] GHSA-4gxv-hggr-2473: In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: serialize hash resizes and cleanups
Syzbot was able to tri
In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: serialize hash resizes and cleanups
Syzbot was able to trigger the following warning [1]
No repro found by syzbot yet but I was able to trigger similar issue
by having 2 scripts running in parallel, changing conntrack hash sizes,
and:
for j in `seq 1 1000` ; do unshare -n /bin/true >/dev/null ; done
It would take more than 5 minutes for net_namespace structures
to be cleaned up.
This is because nf_ct_iterate_cleanup() has to restart everytime
a resize happened.
By adding a mutex, we can serialize hash resizes and cleanups
and also make get_next_corpse() faster by skipping over empty
buckets.
Even without resizes in the picture, this patch considerably
speeds up network namespace dismantles.
[
Red Hat
kernel: netfilter: conntrack: serialize hash resizes and cleanups
vendor_redhat·2024-05-21·CVSS 5.5
CVE-2021-47408 [MEDIUM] CWE-667 kernel: netfilter: conntrack: serialize hash resizes and cleanups
kernel: netfilter: conntrack: serialize hash resizes and cleanups
In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: serialize hash resizes and cleanups
Syzbot was able to trigger the following warning [1]
No repro found by syzbot yet but I was able to trigger similar issue
by having 2 scripts running in parallel, changing conntrack hash sizes,
and:
for j in `seq 1 1000` ; do unshare -n /bin/true >/dev/null ; done
It would take more than 5 minutes for net_namespace structures
to be cleaned up.
This is because nf_ct_iterate_cleanup() has to restart everytime
a resize happened.
By adding a mutex, we can serialize hash resizes and cleanups
and also make get_next_corpse() faster by skipping over empty
buckets.
Even without resizes in the picture, this pa
Debian
CVE-2021-47408: linux - In the Linux kernel, the following vulnerability has been resolved: netfilter: ...
vendor_debian·2021·CVSS 5.5
CVE-2021-47408 [MEDIUM] CVE-2021-47408: linux - In the Linux kernel, the following vulnerability has been resolved: netfilter: ...
In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: serialize hash resizes and cleanups Syzbot was able to trigger the following warning [1] No repro found by syzbot yet but I was able to trigger similar issue by having 2 scripts running in parallel, changing conntrack hash sizes, and: for j in `seq 1 1000` ; do unshare -n /bin/true >/dev/null ; done It would take more than 5 minutes for net_namespace structures to be cleaned up. This is because nf_ct_iterate_cleanup() has to restart everytime a resize happened. By adding a mutex, we can serialize hash resizes and cleanups and also make get_next_corpse() faster by skipping over empty buckets. Even without resizes in the picture, this patch considerably speeds up network namespace dismantles. [1] INFO:
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/7ea6f5848281182ce0cff6cafdcf3fbdeb8ca7e1https://git.kernel.org/stable/c/e2d192301a0df8160d1555b66ae8611e8050e424https://git.kernel.org/stable/c/e9edc188fc76499b0b9bd60364084037f6d03773https://git.kernel.org/stable/c/7ea6f5848281182ce0cff6cafdcf3fbdeb8ca7e1https://git.kernel.org/stable/c/e2d192301a0df8160d1555b66ae8611e8050e424https://git.kernel.org/stable/c/e9edc188fc76499b0b9bd60364084037f6d03773
2024-05-21
Published