Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix stack slot index in nospec checks check_stack_write_fixed_off() computes the byte slot for a fixed-offset stack write as -off - 1, and records each written byte in slot_type[] with (slot - i) % BPF_REG_SIZE. The Spectre v4 sanitization pre-check uses slot_type[i] instead. For a 4-byte write at fp-8 after the lower half of fp-8 has been zeroed, the pre-check scans bytes 0..3 and sees STACK_ZERO while the actual write updates bytes 7..4. That can leave the second half-slot write without nospec_result even though the bytes being overwritten still require sanitization. Use the same slot index in the sanitization pre-check that the write path uses when updating slot_type[].
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 0e9280654aa482088ee6ef3deadef331f5ac5fb0 before e62268e695075a481a6c4feeb022c19cf57422a6; affected 2039f26f3aca5b0e419b98f65dd36481337b86ee before a71eb8f730a91271cf47ce291e785b6b7e54622f; affected 2039f26f3aca5b0e419b98f65dd36481337b86ee before ca119656baa8f48a56e0c2f3ab63fdd33ca9e307; affected 2039f26f3aca5b0e419b98f65dd36481337b86ee before 475405593de2b796224c6297aece44f321195919; affected 2039f26f3aca5b0e419b98f65dd36481337b86ee before f1471aa76d74e0df3b2a90731ca0208f498c670b; affected 2039f26f3aca5b0e419b98f65dd36481337b86ee before 68b41e68a62299f26cb16af422b5c7d1c69dafd9; affected 2039f26f3aca5b0e419b98f65dd36481337b86ee before db8f1dcf5950b91886b9df4270bc816370d292c1; affected 2039f26f3aca5b0e419b98f65dd36481337b86ee before d1d53aa30ab3b5ae89161c9cc840b3f7489ad386; affected 872968502114d68c21419cf7eb5ab97717e7b803; affected f5893af2704eb763eb982f01d573f5b19f06b623; affected 0b27bdf02c400684225ee5ee99970bcbf5082282; affected 5.10.56 before 5.10.261; affected 4.19.207 before 4.20; affected 5.4.146 before 5.5; affected 5.13.8 before 5.14 |
| Linux / Linux | affected 5.14; unaffected 0 before 5.14; unaffected 5.10.261 through 5.10.*; unaffected 5.15.212 through 5.15.*; unaffected 6.1.178 through 6.1.*; unaffected 6.6.145 through 6.6.*; unaffected 6.12.97 through 6.12.*; unaffected 6.18.40 through 6.18.*; unaffected 7.1.5 through 7.1.*; unaffected 7.2 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/e62268e695075a481a6c4feeb022c19cf57422a6
- https://git.kernel.org/stable/c/a71eb8f730a91271cf47ce291e785b6b7e54622f
- https://git.kernel.org/stable/c/ca119656baa8f48a56e0c2f3ab63fdd33ca9e307
- https://git.kernel.org/stable/c/475405593de2b796224c6297aece44f321195919
- https://git.kernel.org/stable/c/f1471aa76d74e0df3b2a90731ca0208f498c670b
- https://git.kernel.org/stable/c/68b41e68a62299f26cb16af422b5c7d1c69dafd9
- https://git.kernel.org/stable/c/db8f1dcf5950b91886b9df4270bc816370d292c1
- https://git.kernel.org/stable/c/d1d53aa30ab3b5ae89161c9cc840b3f7489ad386