{"id":"DEBIAN-CVE-2026-90269","details":"In the Linux kernel, the following vulnerability has been resolved:  bpf: Reject load-acquire from pointers requiring fault protection  A BPF_LOAD_ACQ is not rewritten to a BPF_PROBE_MEM load by the verifier, unlike a regular BPF_LDX, so the JIT emits a plain load with no exception table entry and a fault panics the kernel instead of being handled.  Reject the source pointer types that a BPF_LDX would have had that fault protection applied to, i.e. the ones bpf_convert_ctx_accesses() turns into BPF_PROBE_MEM: a bare PTR_TO_BTF_ID, PTR_TO_BTF_ID | PTR_UNTRUSTED, PTR_TO_BTF_ID | MEM_ALLOC | PTR_UNTRUSTED and PTR_TO_MEM | MEM_RDONLY | PTR_UNTRUSTED.  This is reachable e.g. by loading -\u003emm out of a trusted task_struct yields an untrusted pointer to mm_struct, and it is NULL for a kernel thread:    [...]   SEC(\"tp_btf/sched_switch\")   int BPF_PROG(demo, bool preempt, struct task_struct *prev,                struct task_struct *next)   {       struct mm_struct *mm = next-\u003emm;  /* untrusted */        out_ldx = (__u64)mm-\u003epgd;         /* BPF_LDX      */       out_acq = load_acquire(&mm-\u003epgd); /* BPF_LOAD_ACQ */       return 0;   }   [...]  Both dereference the same pointer, but only the BPF_LDX is protected (x86-64 JIT, jump targets shown prog-relative):    [...]   ; out_ldx = (__u64)mm-\u003epgd;   17:   movq    $-10485760, %r10   1e:   movq    %rsi, %r11   21:   addq    $184, %r11   28:   subq    %r10, %r11   2b:   movabsq $140737498841088, %r10   35:   cmpq    %r10, %r11   38:   ja      0x3e                 \u003c-- kernel addr?   3a:   xorl    %edi, %edi           \u003c-- no: dst = 0, skip the load   3c:   jmp     0x45   3e:   movq    184(%rsi), %rdi      \u003c-- yes: load + extable entry   [...]   ; load_acquire(&mm-\u003epgd)   53:\tmovq    %rsi, %rdi   56:\tmovq    184(%rdi), %rax       \u003c-- no check, no extable entry   [...]  Note that BPF_PROBE_MEM is not visible in a bpftool xlated dump, as bpf_insn_prepare_dump() rewrites it back to BPF_MEM.  A PTR_TRUSTED pointer is deliberately not on the list. Such a load is not converted either, but it does not need to be, since the pointer is guaranteed live, so load-acquire from it stays allowed.  The check is gated on BPF_LOAD_ACQ so that atomic RMW and store-release error messages are unchanged; writes (RMW / store-release) to such pointers are already rejected elsewhere, so only load-acquire needs this.","modified":"2026-09-23T04:01:50.685940554Z","published":"2026-09-17T17:17:23.460Z","upstream":["CVE-2026-90269"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-90269"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.2.6-1"}]}],"versions":["6.12.100-1","6.12.101-1","6.12.105-1","6.12.107-1","6.12.38-1","6.12.41-1","6.12.43-1","6.12.43-1~bpo12+1","6.12.48-1","6.12.57-1","6.12.57-1~bpo12+1","6.12.63-1","6.12.63-1~bpo12+1","6.12.69-1","6.12.69-1~bpo12+1","6.12.73-1","6.12.73-1~bpo12+1","6.12.74-1","6.12.74-2","6.12.74-2~bpo12+1","6.12.85-1","6.12.85-1~bpo12+1","6.12.86-1","6.12.86-1~bpo12+1","6.12.88-1","6.12.88-1~bpo12+1","6.12.90-1","6.12.90-1~bpo12+1","6.12.90-2","6.12.90-2~bpo12+1","6.12.94-1","6.12.94-1~bpo12+1","6.12.95-1","6.12.95-1~bpo12+1","6.12.96-1","6.13.10-1~exp1","6.13.11-1~exp1","6.13.2-1~exp1","6.13.3-1~exp1","6.13.4-1~exp1","6.13.5-1~exp1","6.13.6-1~exp1","6.13.7-1~exp1","6.13.8-1~exp1","6.13.9-1~exp1","6.13~rc6-1~exp1","6.13~rc7-1~exp1","6.14.3-1~exp1","6.14.5-1~exp1","6.14.6-1~exp1","6.15-1~exp1","6.15.1-1~exp1","6.15.2-1~exp1","6.15.3-1~exp1","6.15.4-1~exp1","6.15.5-1~exp1","6.15.6-1~exp1","6.15~rc7-1~exp1","6.16-1~exp1","6.16.1-1~exp1","6.16.10-1","6.16.11-1","6.16.12-1","6.16.12-1~bpo13+1","6.16.12-2","6.16.3-1","6.16.3-1~bpo13+1","6.16.5-1","6.16.6-1","6.16.7-1","6.16.8-1","6.16.9-1","6.16~rc7-1~exp1","6.17.10-1","6.17.11-1","6.17.12-1","6.17.13-1","6.17.13-1~bpo13+1","6.17.2-1~exp1","6.17.5-1~exp1","6.17.6-1","6.17.7-1","6.17.7-2","6.17.8-1","6.17.8-1~bpo13+1","6.17.9-1","6.18.1-1~exp1","6.18.10-1","6.18.12-1","6.18.12-1~bpo13+1","6.18.13-1","6.18.14-1","6.18.15-1","6.18.15-1~bpo13+1","6.18.2-1~exp1","6.18.3-1","6.18.5-1","6.18.5-1~bpo13+1","6.18.8-1","6.18.9-1","6.18.9-1~bpo13+1","6.18~rc4-1~exp1","6.18~rc4-1~exp2","6.18~rc5-1~exp1","6.18~rc6-1~exp1","6.18~rc7-1~exp1","6.19-1~exp1","6.19.10-1","6.19.10-1~bpo13+1","6.19.11-1","6.19.11-1~bpo13+1","6.19.12-1","6.19.13-1","6.19.13-1~bpo13+1","6.19.14-1","6.19.14-1~bpo13+1","6.19.2-1~exp1","6.19.3-1~exp1","6.19.4-1~exp1","6.19.5-1~exp1","6.19.6-1","6.19.6-2","6.19.6-2~bpo13+1","6.19.8-1","6.19.8-1~bpo13+1","6.19~rc4-1~exp1","6.19~rc5-1~exp1","6.19~rc6-1~exp1","6.19~rc7-1~exp1","6.19~rc8-1~exp1","7.0-1~exp1","7.0.1-1~exp1","7.0.10-1","7.0.10-1~bpo13+1","7.0.12-1","7.0.12-2","7.0.12-2~bpo13+1","7.0.13-1","7.0.13-1~bpo13+1","7.0.14-1","7.0.3-1","7.0.4-1","7.0.4-1~bpo13+1","7.0.7-1","7.0.7-1~bpo13+1","7.0.9-1","7.0.9-1~bpo13+1","7.1.1-1~exp1","7.1.10-1","7.1.12-1","7.1.13-1","7.1.2-1~exp1","7.1.3-1","7.1.3-1+sunvdc","7.1.3-1~bpo13+1","7.1.4-1","7.1.5-1","7.1.6-1","7.1.7-1","7.1.7-1~bpo13+1","7.1.8-1","7.1.8-1~bpo13+1","7.1.8-2","7.1.9-1","7.1.9-1+sparc64","7.1~rc2-1~exp1","7.1~rc3-1~exp1","7.1~rc4-1~exp1","7.1~rc4-1~exp2","7.1~rc5-1~exp1","7.1~rc7-1~exp1","7.2.2-1~exp1","7.2.3-1~exp1","7.2~rc3-1~exp1","7.2~rc5-1~exp1","7.2~rc7-1~exp1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-90269.json"}}],"schema_version":"1.9.0"}