Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix same-register dst/src OOB read and pointer leak in sock_ops When a BPF sock_ops program accesses ctx fields with dst_reg == src_reg, the SOCK_OPS_GET_SK() and SOCK_OPS_GET_FIELD() macros fail to zero the destination register in the !fullsock / !locked_tcp_sock path. Both macros borrow a temporary register to check is_fullsock / is_locked_tcp_sock when dst_reg == src_reg, because dst_reg holds the ctx pointer. When the check is false (e.g., TCP_NEW_SYN_RECV state with a request_sock), dst_reg should be zeroed but is not, leaving the stale ctx pointer: - SOCK_OPS_GET_SK: dst_reg retains the ctx pointer, passes NULL checks as PTR_TO_SOCKET_OR_NULL, and can be used as a bogus socket pointer, leading to stack-out-of-bounds access in helpers like bpf_skc_to_tcp6_sock(). - SOCK_OPS_GET_FIELD: dst_reg retains the ctx pointer which the verifier believes is a SCALAR_VALUE, leaking a kernel pointer. Fix both macros by: - Changing JMP_A(1) to JMP_A(2) in the fullsock path to skip the added instruction. - Adding BPF_MOV64_IMM(si->dst_reg, 0) after the temp register restore in the !fullsock path, placed after the restore because dst_reg == src_reg means we need src_reg intact to read ctx->temp.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected fd09af010788a884de1c39537c288830c3d305db before db1200ec2c3ddf119d4d9ba67982063df06bbacb; affected fd09af010788a884de1c39537c288830c3d305db before 4c1c5efd9d1d74743d41ce4e1600501b4feb6827; affected fd09af010788a884de1c39537c288830c3d305db before 0e6b30657bbc771f38025c828d722b6162428508; affected fd09af010788a884de1c39537c288830c3d305db before 64eaf4ecda007140ddcdb28e00c48c9c69aaba39; affected fd09af010788a884de1c39537c288830c3d305db before 2a2c98141e0a75f2d4a7d78b0316c88b3da784ac; affected fd09af010788a884de1c39537c288830c3d305db before 22400725de070b787cd6d806c5795370ab46d269; affected fd09af010788a884de1c39537c288830c3d305db before 18e3ffde1822f0b48b1753bf34aa97ce839df1d8; affected fd09af010788a884de1c39537c288830c3d305db before 10f86a2a5c91fc4c4d001960f1c21abe52545ef6; affected 48be3df15aa19c04eadf156c9129293c9a10389f; affected cd4644d904e1d153d516e73e2e127e7a2fe687e1; affected 6e0bc946cbeec538322820786b5fb5200a2216ab; affected a7e52f7f675046d9ffc5692d815fa67c82fcdbf5; affected db7f8c57dbdd31f7e59f8dc8d1e1b38607a320ef; affected 5.7.18 before 5.8; affected 5.8.4 before 5.9; affected 5.4.61 before 5.5 |
| Linux / Linux | affected 5.9; unaffected 0 before 5.9; unaffected 5.10.270 through 5.10.*; unaffected 5.15.221 through 5.15.*; unaffected 6.1.188 through 6.1.*; unaffected 6.6.157 through 6.6.*; unaffected 6.12.101 through 6.12.*; unaffected 6.18.42 through 6.18.*; unaffected 7.0.10 through 7.0.*; unaffected 7.1 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/db1200ec2c3ddf119d4d9ba67982063df06bbacb
- https://git.kernel.org/stable/c/4c1c5efd9d1d74743d41ce4e1600501b4feb6827
- https://git.kernel.org/stable/c/0e6b30657bbc771f38025c828d722b6162428508
- https://git.kernel.org/stable/c/64eaf4ecda007140ddcdb28e00c48c9c69aaba39
- https://git.kernel.org/stable/c/2a2c98141e0a75f2d4a7d78b0316c88b3da784ac
- https://git.kernel.org/stable/c/22400725de070b787cd6d806c5795370ab46d269
- https://git.kernel.org/stable/c/18e3ffde1822f0b48b1753bf34aa97ce839df1d8
- https://git.kernel.org/stable/c/10f86a2a5c91fc4c4d001960f1c21abe52545ef6
ADP enrichment
No English description supplied.
No references supplied.