{"id":"CVE-2026-74400","summary":"bpf: fix crash in bpf_[set|remove]_dentry_xattr for negative dentries","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: fix crash in bpf_[set|remove]_dentry_xattr for negative dentries\n\nbpf_set_dentry_xattr and bpf_remove_dentry_xattr BPF kfuncs attempt to\nlock the inode of the supplied dentry without checking if it is\nNULL. If a negative dentry is passed (e.g. from\nsecurity_inode_create), d_inode(dentry) returns NULL, and\ninode_lock(inode) will cause a NULL pointer dereference.\n\nTrivially fix this by adding a NULL check for inode before attempting\nto lock it, returning -EINVAL if it is NULL.\n\nAdditionally, drop WARN_ON(!inode) in bpf_xattr_read_permission() and\nbpf_xattr_write_permission(). These warnings could be triggered by\npassing a negative dentry to bpf_get_dentry_xattr() or the _locked\nvariants of the xattr kfuncs, potentially causing a Denial of Service\non systems with panic_on_warn enabled. Instead, simply return -EINVAL.","modified":"2026-08-18T03:31:06.672724339Z","published":"2026-08-15T05:59:11.450Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74400.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0160edf2af51c5fde742973742c5d10497901b21"},{"type":"WEB","url":"https://git.kernel.org/stable/c/07410646f6ff1d23222f105ccab778957d401bbe"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e003f3a4be738f650e283e92d07017c3fef8da52"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74400.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74400"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"56467292794b800164df20c076c409ac548e56ec"},{"fixed":"e003f3a4be738f650e283e92d07017c3fef8da52"},{"fixed":"0160edf2af51c5fde742973742c5d10497901b21"},{"fixed":"07410646f6ff1d23222f105ccab778957d401bbe"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74400.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.15.0"},{"fixed":"6.18.40"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74400.json"}}],"schema_version":"1.9.0"}