cbcvebase.
CVE-2026-52910
published 2026-06-19

CVE-2026-52910: In the Linux kernel, the following vulnerability has been resolved: bpf: Free reuseport cBPF prog after RCU grace period. Eulgyu Kim reported the splat below…

PriorityP340high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.10%
1.2th percentile
In the Linux kernel, the following vulnerability has been resolved: bpf: Free reuseport cBPF prog after RCU grace period. Eulgyu Kim reported the splat below with a repro. [0] The repro sets up a UDP reuseport group with a cBPF prog and replaces it with a new one while another thread is sending a UDP packet to the group. The reuseport prog is freed by sk_reuseport_prog_free(). bpf_prog_put() is called for "e"BPF prog to destruct through multiple stages while cBPF prog is freed immediately by bpf_release_orig_filter() and bpf_prog_free(). If a reuseport prog is detached from the setsockopt() path (reuseport_attach_prog() or reuseport_detach_prog()), sk_reuseport_prog_free() is called without waiting for RCU readers to complete, resulting in various bugs. Let's defer freeing the reuseport cBPF prog after one RCU grace period. Note "e"BPF prog is safe as is unless the fast path starts to touch fields destroyed in bpf_prog_put_deferred() and __bpf_prog_put_noref(). [0]: BUG: KASAN: vmalloc-out-of-bounds in reuseport_select_sock+0xedc/0x1220 net/core/sock_reuseport.c:596 Read of size 4 at addr ffffc9000051e004 by task slowme/10208 CPU: 6 UID: 1000 PID: 10208 Comm: slowme Not tainted 7.0.0-geb7ac95ff75e #32 PREEMPT(full) Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 reuseport_select_sock+0xedc/0x1220 net/core/sock_reuseport.c:596 udp4_lib_lookup2+0x3bc/0x950 net/ipv4/udp.c:495 __udp4_lib_lookup+0x768/0xe20 net/ipv4/udp.c:723 __udp4_lib_lookup_skb+0x297/0x390 net/ipv4/udp.c:752 __udp4_lib_rcv+0x1312/0x2620 net/ipv4/udp.c:2752 ip_protocol_deliver_rcu+0x282/0x440 net/ipv4/ip_input.c:207 ip_local_deliver_finish+0x3bb/0x6f0 net/ipv4/ip_input.c:241 NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:3

Affected

19 ranges
VendorProductVersion rangeFixed in
linuxlinux
linuxlinux>= 538950a1b7527a0a52ccd9337e3fcd304f027f13 < 08264d5bba0bdd3a79bc2984fee09286aba0c4eb08264d5bba0bdd3a79bc2984fee09286aba0c4eb
linuxlinux>= 538950a1b7527a0a52ccd9337e3fcd304f027f13 < fec41484e7c2aa7ded44c541bba98872be937754fec41484e7c2aa7ded44c541bba98872be937754
linuxlinux>= 538950a1b7527a0a52ccd9337e3fcd304f027f13 < c3e3fddda6b5d9ba505d218b4055e7d8a282ac57c3e3fddda6b5d9ba505d218b4055e7d8a282ac57
linuxlinux>= 538950a1b7527a0a52ccd9337e3fcd304f027f13 < f8b8f1d4bb76098e87b8269a0631019648330e6df8b8f1d4bb76098e87b8269a0631019648330e6d
linuxlinux>= 538950a1b7527a0a52ccd9337e3fcd304f027f13 < 298db6167f81e9c470a57cf652e4e47757b4293e298db6167f81e9c470a57cf652e4e47757b4293e
linuxlinux>= 538950a1b7527a0a52ccd9337e3fcd304f027f13 < 87dfb977bdb6eaa47e9993a34e18f44970f88b1f87dfb977bdb6eaa47e9993a34e18f44970f88b1f
linuxlinux>= 538950a1b7527a0a52ccd9337e3fcd304f027f13 < 90e47dc5c572d1c73971ac51c7428803f42b78eb90e47dc5c572d1c73971ac51c7428803f42b78eb
linuxlinux>= 538950a1b7527a0a52ccd9337e3fcd304f027f13 < 18fc650ccd7fe3376eca89203668cfb8268f60df18fc650ccd7fe3376eca89203668cfb8268f60df
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 4.5 < 5.10.2595.10.259
linuxlinux_kernel>= 5.11 < 5.15.2105.15.210
linuxlinux_kernel>= 5.16 < 6.1.1766.1.176
linuxlinux_kernel>= 6.13 < 6.18.366.18.36
linuxlinux_kernel>= 6.19 < 7.0.137.0.13
linuxlinux_kernel>= 6.2 < 6.6.1436.6.143
linuxlinux_kernel>= 6.7 < 6.12.946.12.94

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
vendor_redhat7.0HIGH
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