Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_hfsc: fix divide-by-zero in rtsc_min() m2sm() converts a u32 slope to a u64 scaled value. For large inputs (e.g. m1=4000000000), the result can reach 2^32. rtsc_min() stores the difference of two such u64 values in a u32 variable `dsm` and uses it as a divisor. When the difference is exactly 2^32 the truncation yields zero, causing a divide-by-zero oops in the concave-curve intersection path: Oops: divide error: 0000 RIP: 0010:rtsc_min (net/sched/sch_hfsc.c:601) Call Trace: init_ed (net/sched/sch_hfsc.c:629) hfsc_enqueue (net/sched/sch_hfsc.c:1569) [...] Widen `dsm` to u64 and replace do_div() with div64_u64() so the full difference is preserved.
Affected products
linux: linux kernel
References10
- git.kernel.org/stable/c/17c1b9807b8a67d676b6dcf749ee932ebaa7f568 Patch
- git.kernel.org/stable/c/25b6821884713a31e2b49fb67b0ebd765b33e0a9 Patch
- git.kernel.org/stable/c/4576100b8cd03118267513cafacde164b498b322 Patch
- git.kernel.org/stable/c/ab1ff5890c7354afc7be56502fcfbd61f3b7ae4f Patch
- git.kernel.org/stable/c/ad8e8fec40290a8c8cf145c0deaadf76f80c5163 Patch
- git.kernel.org/stable/c/b9e6431cbea8bb1fae8069ed099b4ee100499835 Patch
- git.kernel.org/stable/c/c56f78614e7781aaceca9bd3cb2128bf7d45c3bd Patch
- git.kernel.org/stable/c/d0aefec1b1a1ba2c1d251028dc2c4e5b4ce1fea5 Patch
- cert-portal.siemens.com/productcert/html/ssa-019113.html
- cert-portal.siemens.com/productcert/html/ssa-082556.html
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 2 · as of 12 November 2026
- CWE
- CWE-369
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