Description
In the Linux kernel, the following vulnerability has been resolved: net: dsa: bcm_sf2: bound the CFP rule dump by the caller's buffer size bcm_sf2_cfp_rule_get_all() walks the whole cfp.unique bitmap into rule_locs[] without consulting nfc->rule_cnt, which is how many entries the caller had room for. ETHTOOL_GRXCLSRLALL requires no CAP_NET_ADMIN and the ioctl sizes the buffer from the rule_cnt userspace passes in, so once an admin has installed CFP rules any user can ask for fewer slots than there are rules and run off the end of the allocation. A rule_cnt of 0 leaves the buffer pointer NULL and the walk dereferences it.
References8
- git.kernel.org/stable/c/8e41ce02589c92356bfd8ef62f6ceff840546e1a
- git.kernel.org/stable/c/b231b6d8516d3fe0d4bba549908e08d26a4531a5
- git.kernel.org/stable/c/ca49c526291d7cd3a5cb49b0edd7f50a5ae7176e
- git.kernel.org/stable/c/cdb719f4b8596d9ccee2d56d204c2c4dce982f46
- git.kernel.org/stable/c/f1a2869b3629c0e8394b77b38cb9f19a018c653c
- git.kernel.org/stable/c/f2cf4ef2d94fc15fd2e21c131fc1ab3f76125bf4
- git.kernel.org/stable/c/f5e93162b3dd195bfda815e8f7a39aaf1d45437b
- git.kernel.org/stable/c/fd1a78c16b1f6978c09cf048e15f349732e4c707
Metrics
- CVSS 3.1
-
7.0
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 2 · as of 9 November 2026
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