5.15-stable review patch. If anyone has any objections, please let me know.
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From: Jarkko Sakkinen jarkko@kernel.org
commit 050bf3c793a07f96bd1e2fd62e1447f731ed733b upstream.
When asn1_encode_sequence() fails, WARN is not the correct solution.
1. asn1_encode_sequence() is not an internal function (located in lib/asn1_encode.c). 2. Location is known, which makes the stack trace useless. 3. Results a crash if panic_on_warn is set.
It is also noteworthy that the use of WARN is undocumented, and it should be avoided unless there is a carefully considered rationale to use it.
Replace WARN with pr_err, and print the return value instead, which is only useful piece of information.
Cc: stable@vger.kernel.org # v5.13+ Fixes: f2219745250f ("security: keys: trusted: use ASN.1 TPM2 key format for the blobs") Signed-off-by: Jarkko Sakkinen jarkko@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- security/keys/trusted-keys/trusted_tpm2.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/security/keys/trusted-keys/trusted_tpm2.c +++ b/security/keys/trusted-keys/trusted_tpm2.c @@ -84,8 +84,9 @@ static int tpm2_key_encode(struct truste work1 = payload->blob; work1 = asn1_encode_sequence(work1, work1 + sizeof(payload->blob), scratch, work - scratch); - if (WARN(IS_ERR(work1), "BUG: ASN.1 encoder failed")) { + if (IS_ERR(work1)) { ret = PTR_ERR(work1); + pr_err("BUG: ASN.1 encoder failed with %d\n", ret); goto err; }