Bug 2548394 (CVE-2026-98384)

Summary: CVE-2026-98384 kernel: bpf: Fix out-of-bounds read of sk_protocol in bpf_sock_destroy()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's Berkeley Packet Filter (BPF) subsystem. When processing socket destruction requests through the bpf_sock_destroy() helper, the kernel fails to properly verify if a socket is a full socket before attempting to read its protocol field, causing an out-of-bounds memory read. A local user authorized to execute BPF programs can exploit this vulnerability to cause a system crash, resulting in a Denial of Service (DoS), or potentially disclose sensitive kernel memory.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-10-09 08:01:41 UTC 
In the Linux kernel, the following vulnerability has been resolved:

bpf: Fix out-of-bounds read of sk_protocol in bpf_sock_destroy()

sk_protocol lives in struct sock, not in struct sock_common. A timewait
or request sock handed to bpf_sock_destroy() by the tcp iterator is
neither, so reading sk->sk_protocol runs past the object:

==================================================================
BUG: KASAN: slab-out-of-bounds in bpf_sock_destroy+0xc7/0xe0
Read of size 2 at addr ffff8881047d11b4 by task test_progs/428

Tainted: [W]=WARN
Call Trace:
 <TASK>
 dump_stack_lvl+0x91/0xf0
 print_report+0xd1/0x630
 kasan_report+0xf3/0x130
 __asan_report_load2_noabort+0x14/0x30
 bpf_sock_destroy+0xc7/0xe0
 bpf_prog_c3dd61f9d9cd9f37_iter_tcp6_timewait+0x9f/0xb7
 bpf_iter_run_prog+0x538/0xde0
 bpf_iter_tcp_seq_show+0x26b/0x4b0
 bpf_seq_read+0x424/0x1210
 vfs_read+0x197/0xe40
 ksys_read+0x119/0x240
 __x64_sys_read+0x72/0xc0
 x64_sys_call+0x647/0x27e0
 do_syscall_64+0xe5/0x610
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Only check sk_protocol on full socks. tcp_abort() already knows how to
deal with TIME_WAIT and NEW_SYN_RECV socks. Also fix the comment, it
never matched the code.
Comment 1 gkamathe 2026-10-10 16:21:36 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98384.mbox