From: Norbert Szetei <norbert@doyensec.com> stable inclusion from stable-v6.6.134 commit 7cdf2c6381b21ab5ccf8116750d5582fcd6c0f49 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/14575 CVE: CVE-2026-43043 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 62397b493e14107ae82d8b80938f293d95425bcb ] The AF_ALG interface fails to unmark the end of a Scatter/Gather List (SGL) when chaining a new af_alg_tsgl structure. If a sendmsg() fills an SGL exactly to MAX_SGL_ENTS, the last entry is marked as the end. A subsequent sendmsg() allocates a new SGL and chains it, but fails to clear the end marker on the previous SGL's last data entry. This causes the crypto scatterwalk to hit a premature end, returning NULL on sg_next() and leading to a kernel panic during dereference. Fix this by explicitly unmarking the end of the previous SGL when performing sg_chain() in af_alg_alloc_tsgl(). Fixes: 8ff590903d5f ("crypto: algif_skcipher - User-space interface for skcipher operations") Signed-off-by: Norbert Szetei <norbert@doyensec.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Yi Yang <yiyang13@huawei.com> --- crypto/af_alg.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/crypto/af_alg.c b/crypto/af_alg.c index 1765ac34c2d4..b0a4211345ab 100644 --- a/crypto/af_alg.c +++ b/crypto/af_alg.c @@ -622,8 +622,10 @@ static int af_alg_alloc_tsgl(struct sock *sk) sg_init_table(sgl->sg, MAX_SGL_ENTS + 1); sgl->cur = 0; - if (sg) + if (sg) { + sg_unmark_end(sg + MAX_SGL_ENTS - 1); sg_chain(sg, MAX_SGL_ENTS + 1, sgl->sg); + } list_add_tail(&sgl->list, &ctx->tsgl_list); } -- 2.25.1