CVE-2021-47496 (GCVE-0-2021-47496)
Vulnerability from cvelistv5
Published
2024-05-22 08:19
Modified
2026-08-05 08:48
Severity ?
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: net/tls: Fix flipped sign in tls_err_abort() calls sk->sk_err appears to expect a positive value, a convention that ktls doesn't always follow and that leads to memory corruption in other code. For instance, [kworker] tls_encrypt_done(..., err=<negative error from crypto request>) tls_err_abort(.., err) sk->sk_err = err; [task] splice_from_pipe_feed ... tls_sw_do_sendpage if (sk->sk_err) { ret = -sk->sk_err; // ret is positive splice_from_pipe_feed (continued) ret = actor(...) // ret is still positive and interpreted as bytes // written, resulting in underflow of buf->len and // sd->len, leading to huge buf->offset and bogus // addresses computed in later calls to actor() Fix all tls_err_abort() callers to pass a negative error code consistently and centralize the error-prone sign flip there, throwing in a warning to catch future misuse and uninlining the function so it really does only warn once.
References
Impacted products
Vendor Product Version
Linux Linux Version: c46234ebb4d1eee5e09819f49169e51cfc6eb909
Version: c46234ebb4d1eee5e09819f49169e51cfc6eb909
Version: c46234ebb4d1eee5e09819f49169e51cfc6eb909
Version: c46234ebb4d1eee5e09819f49169e51cfc6eb909
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