Description
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
Product status
afe4fd062416b158a8a8538b23adc1930a9b88dc before 4b8a05e3801661a0438fcd0cdef181030d966a5a
afe4fd062416b158a8a8538b23adc1930a9b88dc before d0b43125ec892aeb1b03e5df5aab595097da225a
afe4fd062416b158a8a8538b23adc1930a9b88dc before 4fbefeab88c6e79753a25099d455d3d59d2946b4
afe4fd062416b158a8a8538b23adc1930a9b88dc before 85f24cb2f10b2b0f2882e5786a09b4790bb3a0ad
afe4fd062416b158a8a8538b23adc1930a9b88dc before 2322462d6f9ad4874f4e3c63df3b5cc00cb1acbd
afe4fd062416b158a8a8538b23adc1930a9b88dc before 7041101ff6c3073fd8f2e99920f535b111c929cb
3.12
Any version before 3.12
5.10.180
5.15.111
6.1.28
6.2.15
6.3.2
6.4
References
git.kernel.org/...c/4b8a05e3801661a0438fcd0cdef181030d966a5a
git.kernel.org/...c/d0b43125ec892aeb1b03e5df5aab595097da225a
git.kernel.org/...c/4fbefeab88c6e79753a25099d455d3d59d2946b4
git.kernel.org/...c/85f24cb2f10b2b0f2882e5786a09b4790bb3a0ad
git.kernel.org/...c/2322462d6f9ad4874f4e3c63df3b5cc00cb1acbd
git.kernel.org/...c/7041101ff6c3073fd8f2e99920f535b111c929cb
