{"id":"CVE-2026-53069","summary":"net, bpf: fix null-ptr-deref in xdp_master_redirect() for down master","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet, bpf: fix null-ptr-deref in xdp_master_redirect() for down master\n\nsyzkaller reported a kernel panic in bond_rr_gen_slave_id() reached via\nxdp_master_redirect(). Full decoded trace:\n\n  https://syzkaller.appspot.com/bug?extid=80e046b8da2820b6ba73\n\nbond_rr_gen_slave_id() dereferences bond-\u003err_tx_counter, a per-CPU\ncounter that bonding only allocates in bond_open() when the mode is\nround-robin. If the bond device was never brought up, rr_tx_counter\nstays NULL.\n\nThe XDP redirect path can still reach that code on a bond that was\nnever opened: bpf_master_redirect_enabled_key is a global static key,\nso as soon as any bond device has native XDP attached, the\nXDP_TX -\u003e xdp_master_redirect() interception is enabled for every\nslave system-wide. The path xdp_master_redirect() -\u003e\nbond_xdp_get_xmit_slave() -\u003e bond_xdp_xmit_roundrobin_slave_get() -\u003e\nbond_rr_gen_slave_id() then runs against a bond that has no\nrr_tx_counter and crashes.\n\nFix this in the generic xdp_master_redirect() by refusing to call into\nthe master's -\u003endo_xdp_get_xmit_slave() when the master device is not\nup. IFF_UP is only set after -\u003endo_open() has successfully returned,\nso this reliably excludes masters whose XDP state has not been fully\ninitialized. Drop the frame with XDP_ABORTED so the exception is\nvisible via trace_xdp_exception() rather than silently falling through.\nThis is not specific to bonding: any current or future master that\ndefers XDP state allocation to -\u003endo_open() is protected.","modified":"2026-07-16T03:31:17.755500893Z","published":"2026-06-24T16:30:10.930Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53069.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/183128da0406b1c10e6f60b7b9fe70788b9c8c1d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/1921f91298d1388a0bb9db8f83800c998b649cb3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3128b294b426533c8d9162187446d93a8a160359"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7bad93e99737e4a5c0c14ac50c05152cf4e28022"},{"type":"WEB","url":"https://git.kernel.org/stable/c/866d3d9b87751b1944168fd82615505e0c0fd6cf"},{"type":"WEB","url":"https://git.kernel.org/stable/c/acbf45bd584d924b320bee2a7fe2a26f64904d95"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ea690b3b6e58ae00979af8195b4cc24df466b65e"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53069.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53069"},{"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":"879af96ffd72706c6e3278ea6b45b0b0e37ec5d7"},{"fixed":"3128b294b426533c8d9162187446d93a8a160359"},{"fixed":"acbf45bd584d924b320bee2a7fe2a26f64904d95"},{"fixed":"866d3d9b87751b1944168fd82615505e0c0fd6cf"},{"fixed":"183128da0406b1c10e6f60b7b9fe70788b9c8c1d"},{"fixed":"7bad93e99737e4a5c0c14ac50c05152cf4e28022"},{"fixed":"ea690b3b6e58ae00979af8195b4cc24df466b65e"},{"fixed":"1921f91298d1388a0bb9db8f83800c998b649cb3"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53069.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.15.0"},{"fixed":"5.15.209"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.175"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.141"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.91"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.33"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.10"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53069.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}