CVE-2022-50177
published 2025-06-18CVE-2022-50177: In the Linux kernel, the following vulnerability has been resolved: rcutorture: Fix ksoftirqd boosting timing and iteration The RCU priority boosting can fail…
PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.20%
10.3th percentile
In the Linux kernel, the following vulnerability has been resolved:
rcutorture: Fix ksoftirqd boosting timing and iteration
The RCU priority boosting can fail in two situations:
1) If (nr_cpus= > maxcpus=), which means if the total number of CPUs
is higher than those brought online at boot, then torture_onoff() may
later bring up CPUs that weren't online on boot. Now since rcutorture
initialization only boosts the ksoftirqds of the CPUs that have been
set online on boot, the CPUs later set online by torture_onoff won't
benefit from the boost, making RCU priority boosting fail.
2) The ksoftirqd kthreads are boosted after the creation of
rcu_torture_boost() kthreads, which opens a window large enough for these
rcu_torture_boost() kthreads to wait (despite running at FIFO priority)
for ksoftirqds that are still running at SCHED_NORMAL priority.
The issues can trigger for example with:
./kvm.sh --configs TREE01 --kconfig "CONFIG_RCU_BOOST=y"
[ 34.968561] rcu-torture: !!!
[ 34.968627] ------------[ cut here ]------------
[ 35.014054] WARNING: CPU: 4 PID: 114 at kernel/rcu/rcutorture.c:1979 rcu_torture_stats_print+0x5ad/0x610
[ 35.052043] Modules linked in:
[ 35.069138] CPU: 4 PID: 114 Comm: rcu_torture_sta Not tainted 5.18.0-rc1 #1
[ 35.096424] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014
[ 35.154570] RIP: 0010:rcu_torture_stats_print+0x5ad/0x610
[ 35.198527] Code: 63 1b 02 00 74 02 0f 0b 48 83 3d 35 63 1b 02 00 74 02 0f 0b 48 83 3d 21 63 1b 02 00 74 02 0f 0b 48 83 3d 0d 63 1b 02 00 74 02 0b 83 eb 01 0f 8e ba fc ff ff 0f 0b e9 b3 fc ff f82
[ 37.251049] RSP: 0000:ffffa92a0050bdf8 EFLAGS: 00010202
[ 37.277320] rcu: De-offloading 8
[ 37.290367] RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001
[ 37.290387] RDX: 0000000000000000 RSI: 00000000ffffbfff RDI: 00000000ffffffff
[ 37.290398] RBP: 000000000000007b R08: 0000000000000000 R09: c0000000ffffbfff
[ 37.290407] R10: 000000000000002a R11
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.0.2-1 (bookworm) | linux 6.0.2-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= ea6d962e80b61996aeacb443661cc3adcb605315 < 621595f771a6bd458ffbc40679e222ba5d0a7a1e | 621595f771a6bd458ffbc40679e222ba5d0a7a1e |
| linux | linux | >= ea6d962e80b61996aeacb443661cc3adcb605315 < 8e84693621f53bf894af9905a6531e0530402145 | 8e84693621f53bf894af9905a6531e0530402145 |
| linux | linux | >= ea6d962e80b61996aeacb443661cc3adcb605315 < 7e7472c62c6ded322afd9d5ac8bb20a08e7c5674 | 7e7472c62c6ded322afd9d5ac8bb20a08e7c5674 |
| linux | linux | >= ea6d962e80b61996aeacb443661cc3adcb605315 < 3002153a91a9732a6d1d0bb95138593c7da15743 | 3002153a91a9732a6d1d0bb95138593c7da15743 |
| linux | linux_kernel | >= 0 < 6.0.2-1 | 6.0.2-1 |
| linux | linux_kernel | >= 0 < 6.0.2-1 | 6.0.2-1 |
| linux | linux_kernel | >= 0 < 6.0.2-1 | 6.0.2-1 |
| linux | linux_kernel | >= 5.14 < 5.15.61 | 5.15.61 |
| linux | linux_kernel | >= 5.16 < 5.18.18 | 5.18.18 |
| linux | linux_kernel | >= 5.19 < 5.19.2 | 5.19.2 |
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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Red Hat
kernel: rcutorture: Fix ksoftirqd boosting timing and iteration
vendor_redhat·2025-06-18·CVSS 5.5
CVE-2022-50177 [MEDIUM] kernel: rcutorture: Fix ksoftirqd boosting timing and iteration
kernel: rcutorture: Fix ksoftirqd boosting timing and iteration
In the Linux kernel, the following vulnerability has been resolved:
rcutorture: Fix ksoftirqd boosting timing and iteration
The RCU priority boosting can fail in two situations:
1) If (nr_cpus= > maxcpus=), which means if the total number of CPUs
is higher than those brought online at boot, then torture_onoff() may
later bring up CPUs that weren't online on boot. Now since rcutorture
initialization only boosts the ksoftirqds of the CPUs that have been
set online on boot, the CPUs later set online by torture_onoff won't
benefit from the boost, making RCU priority boosting fail.
2) The ksoftirqd kthreads are boosted after the creation of
rcu_torture_boost() kthreads, which opens a window large enough for these
rcu_torture_boost
Debian
CVE-2022-50177: linux - In the Linux kernel, the following vulnerability has been resolved: rcutorture:...
vendor_debian·2022·CVSS 5.5
CVE-2022-50177 [MEDIUM] CVE-2022-50177: linux - In the Linux kernel, the following vulnerability has been resolved: rcutorture:...
In the Linux kernel, the following vulnerability has been resolved: rcutorture: Fix ksoftirqd boosting timing and iteration The RCU priority boosting can fail in two situations: 1) If (nr_cpus= > maxcpus=), which means if the total number of CPUs is higher than those brought online at boot, then torture_onoff() may later bring up CPUs that weren't online on boot. Now since rcutorture initialization only boosts the ksoftirqds of the CPUs that have been set online on boot, the CPUs later set online by torture_onoff won't benefit from the boost, making RCU priority boosting fail. 2) The ksoftirqd kthreads are boosted after the creation of rcu_torture_boost() kthreads, which opens a window large enough for these rcu_torture_boost() kthreads to wait (despite running at FIFO priority) for ksofti
OSV
CVE-2022-50177: In the Linux kernel, the following vulnerability has been resolved: rcutorture: Fix ksoftirqd boosting timing and iteration The RCU priority boosting
osv·2025-06-18·CVSS 5.5
CVE-2022-50177 [MEDIUM] CVE-2022-50177: In the Linux kernel, the following vulnerability has been resolved: rcutorture: Fix ksoftirqd boosting timing and iteration The RCU priority boosting
In the Linux kernel, the following vulnerability has been resolved: rcutorture: Fix ksoftirqd boosting timing and iteration The RCU priority boosting can fail in two situations: 1) If (nr_cpus= > maxcpus=), which means if the total number of CPUs is higher than those brought online at boot, then torture_onoff() may later bring up CPUs that weren't online on boot. Now since rcutorture initialization only boosts the ksoftirqds of the CPUs that have been set online on boot, the CPUs later set online by torture_onoff won't benefit from the boost, making RCU priority boosting fail. 2) The ksoftirqd kthreads are boosted after the creation of rcu_torture_boost() kthreads, which opens a window large enough for these rcu_torture_boost() kthreads to wait (despite running at FIFO priority) for ksofti
GHSA
GHSA-g694-9fmr-cmm3: In the Linux kernel, the following vulnerability has been resolved:
rcutorture: Fix ksoftirqd boosting timing and iteration
The RCU priority boostin
ghsa_unreviewed·2025-06-18
CVE-2022-50177 [MEDIUM] GHSA-g694-9fmr-cmm3: In the Linux kernel, the following vulnerability has been resolved:
rcutorture: Fix ksoftirqd boosting timing and iteration
The RCU priority boostin
In the Linux kernel, the following vulnerability has been resolved:
rcutorture: Fix ksoftirqd boosting timing and iteration
The RCU priority boosting can fail in two situations:
1) If (nr_cpus= > maxcpus=), which means if the total number of CPUs
is higher than those brought online at boot, then torture_onoff() may
later bring up CPUs that weren't online on boot. Now since rcutorture
initialization only boosts the ksoftirqds of the CPUs that have been
set online on boot, the CPUs later set online by torture_onoff won't
benefit from the boost, making RCU priority boosting fail.
2) The ksoftirqd kthreads are boosted after the creation of
rcu_torture_boost() kthreads, which opens a window large enough for these
rcu_torture_boost() kthreads to wait (despite running at FIFO priority)
for ks
No detection rules found.
No public exploits indexed.
2025-06-18
Published