Bugzilla – Bug 1224439
VUL-0: CVE-2024-27414: kernel: rtnetlink: fix error logic of IFLA_BRIDGE_FLAGS writing back
Last modified: 2024-07-08 14:47:26 UTC
In the Linux kernel, the following vulnerability has been resolved: rtnetlink: fix error logic of IFLA_BRIDGE_FLAGS writing back In the commit d73ef2d69c0d ("rtnetlink: let rtnl_bridge_setlink checks IFLA_BRIDGE_MODE length"), an adjustment was made to the old loop logic in the function `rtnl_bridge_setlink` to enable the loop to also check the length of the IFLA_BRIDGE_MODE attribute. However, this adjustment removed the `break` statement and led to an error logic of the flags writing back at the end of this function. if (have_flags) memcpy(nla_data(attr), &flags, sizeof(flags)); // attr should point to IFLA_BRIDGE_FLAGS NLA !!! Before the mentioned commit, the `attr` is granted to be IFLA_BRIDGE_FLAGS. However, this is not necessarily true fow now as the updated loop will let the attr point to the last NLA, even an invalid NLA which could cause overflow writes. This patch introduces a new variable `br_flag` to save the NLA pointer that points to IFLA_BRIDGE_FLAGS and uses it to resolve the mentioned error logic. References: http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2024-27414 https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2024/CVE-2024-27414.mbox https://git.kernel.org/stable/c/b9fbc44159dfc3e9a7073032752d9e03f5194a6f https://git.kernel.org/stable/c/882a51a10ecf24ce135d573afa0872aef02c5125 https://git.kernel.org/stable/c/a1227b27fcccc99dc44f912b479e01a17e2d7d31 https://git.kernel.org/stable/c/f2261eb994aa5757c1da046b78e3229a3ece0ad9 https://git.kernel.org/stable/c/167d8642daa6a44b51de17f8ff0f584e1e762db7 https://git.kernel.org/stable/c/831bc2728fb48a8957a824cba8c264b30dca1425 https://git.kernel.org/stable/c/743ad091fb46e622f1b690385bb15e3cd3daf874 https://www.cve.org/CVERecord?id=CVE-2024-27414
https://www.suse.com/security/cve/CVE-2024-27414.html cvss 6.3
Fixed in: SLE15-SP6 6651625572a rtnetlink: fix error logic of IFLA_BRIDGE_FLAGS writing back (CVE-2024-27414 bsc#1224439). Assigning back to the security team