CVE-2023-53624
In the Linux kernel, the following vulnerability has been resolved:
net/sched: sch_fq: fix integer overflow of "credit"
if sch_fq is configured with "initial quantum" having values greater than
INT_MAX, the first assignment of "credit" does signed integer overflow to
a very negative value.
In this situation, the syzkaller script provided by Cristoph triggers the
CPU soft-lockup warning even with few sockets. It's not an infinite loop,
but "credit" wasn't probably meant to be minus 2Gb for each new flow.
Capping "initial quantum" to INT_MAX proved to fix the issue.
v2: validation of "initial quantum" is done in fq_policy, instead of open
coding in fq_change() _ suggested by Jakub Kicinski
net/sched: sch_fq: fix integer overflow of "credit"
if sch_fq is configured with "initial quantum" having values greater than
INT_MAX, the first assignment of "credit" does signed integer overflow to
a very negative value.
In this situation, the syzkaller script provided by Cristoph triggers the
CPU soft-lockup warning even with few sockets. It's not an infinite loop,
but "credit" wasn't probably meant to be minus 2Gb for each new flow.
Capping "initial quantum" to INT_MAX proved to fix the issue.
v2: validation of "initial quantum" is done in fq_policy, instead of open
coding in fq_change() _ suggested by Jakub Kicinski
Vendor
Product
CWE
Yayın Tarihi
2025-10-07 16:15:45
Güncelleme
2026-02-05 14:32:24
Source Identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
KEV Date Added
-
Kategoriler
Referanslar
https://git.kernel.org/stable/c/2322462d6f9ad4874f4e3c63df3b5cc00cb1acbd
https://git.kernel.org/stable/c/4b8a05e3801661a0438fcd0cdef181030d966a5a
https://git.kernel.org/stable/c/4fbefeab88c6e79753a25099d455d3d59d2946b4
https://git.kernel.org/stable/c/7041101ff6c3073fd8f2e99920f535b111c929cb
https://git.kernel.org/stable/c/85f24cb2f10b2b0f2882e5786a09b4790bb3a0ad
https://git.kernel.org/stable/c/d0b43125ec892aeb1b03e5df5aab595097da225a