From: Herbert Xu <herbert@gondor.apana.org.au> stable inclusion from stable-v5.10.254 commit 893d22e0135fa394db81df88697fba6032747667 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/14174 CVE: CVE-2026-31431 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit a664bf3d603dc3bdcf9ae47cc21e0daec706d7a5 upstream. This mostly reverts commit 72548b093ee3 except for the copying of the associated data. There is no benefit in operating in-place in algif_aead since the source and destination come from different mappings. Get rid of all the complexity added for in-place operation and just copy the AD directly. Fixes: 72548b093ee3 ("crypto: algif_aead - copy AAD from src to dst") Reported-by: Taeyang Lee <0wn@theori.io> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Tengda Wu <wutengda2@huawei.com> --- crypto/af_alg.c | 49 +++++--------------- crypto/algif_aead.c | 99 ++++++++--------------------------------- crypto/algif_skcipher.c | 6 +-- include/crypto/if_alg.h | 5 +-- 4 files changed, 34 insertions(+), 125 deletions(-) diff --git a/crypto/af_alg.c b/crypto/af_alg.c index 430cf0f596d1..680c49d83fde 100644 --- a/crypto/af_alg.c +++ b/crypto/af_alg.c @@ -527,15 +527,13 @@ static int af_alg_alloc_tsgl(struct sock *sk) /** * af_alg_count_tsgl - Count number of TX SG entries * - * The counting starts from the beginning of the SGL to @bytes. If - * an @offset is provided, the counting of the SG entries starts at the @offset. + * The counting starts from the beginning of the SGL to @bytes. * * @sk: socket of connection to user space * @bytes: Count the number of SG entries holding given number of bytes. - * @offset: Start the counting of SG entries from the given offset. * Return: Number of TX SG entries found given the constraints */ -unsigned int af_alg_count_tsgl(struct sock *sk, size_t bytes, size_t offset) +unsigned int af_alg_count_tsgl(struct sock *sk, size_t bytes) { const struct alg_sock *ask = alg_sk(sk); const struct af_alg_ctx *ctx = ask->private; @@ -550,25 +548,11 @@ unsigned int af_alg_count_tsgl(struct sock *sk, size_t bytes, size_t offset) const struct scatterlist *sg = sgl->sg; for (i = 0; i < sgl->cur; i++) { - size_t bytes_count; - - /* Skip offset */ - if (offset >= sg[i].length) { - offset -= sg[i].length; - bytes -= sg[i].length; - continue; - } - - bytes_count = sg[i].length - offset; - - offset = 0; sgl_count++; - - /* If we have seen requested number of bytes, stop */ - if (bytes_count >= bytes) + if (sg[i].length >= bytes) return sgl_count; - bytes -= bytes_count; + bytes -= sg[i].length; } } @@ -580,19 +564,14 @@ EXPORT_SYMBOL_GPL(af_alg_count_tsgl); * af_alg_pull_tsgl - Release the specified buffers from TX SGL * * If @dst is non-null, reassign the pages to @dst. The caller must release - * the pages. If @dst_offset is given only reassign the pages to @dst starting - * at the @dst_offset (byte). The caller must ensure that @dst is large - * enough (e.g. by using af_alg_count_tsgl with the same offset). + * the pages. * * @sk: socket of connection to user space * @used: Number of bytes to pull from TX SGL * @dst: If non-NULL, buffer is reassigned to dst SGL instead of releasing. The * caller must release the buffers in dst. - * @dst_offset: Reassign the TX SGL from given offset. All buffers before - * reaching the offset is released. */ -void af_alg_pull_tsgl(struct sock *sk, size_t used, struct scatterlist *dst, - size_t dst_offset) +void af_alg_pull_tsgl(struct sock *sk, size_t used, struct scatterlist *dst) { struct alg_sock *ask = alg_sk(sk); struct af_alg_ctx *ctx = ask->private; @@ -617,18 +596,10 @@ void af_alg_pull_tsgl(struct sock *sk, size_t used, struct scatterlist *dst, * SG entries in dst. */ if (dst) { - if (dst_offset >= plen) { - /* discard page before offset */ - dst_offset -= plen; - } else { - /* reassign page to dst after offset */ - get_page(page); - sg_set_page(dst + j, page, - plen - dst_offset, - sg[i].offset + dst_offset); - dst_offset = 0; - j++; - } + /* reassign page to dst after offset */ + get_page(page); + sg_set_page(dst + j, page, plen, sg[i].offset); + j++; } sg[i].length -= plen; diff --git a/crypto/algif_aead.c b/crypto/algif_aead.c index 38a4ab8c90c7..f59728c021fc 100644 --- a/crypto/algif_aead.c +++ b/crypto/algif_aead.c @@ -26,7 +26,6 @@ #include <crypto/internal/aead.h> #include <crypto/scatterwalk.h> #include <crypto/if_alg.h> -#include <crypto/skcipher.h> #include <linux/init.h> #include <linux/list.h> #include <linux/kernel.h> @@ -72,9 +71,8 @@ static int _aead_recvmsg(struct socket *sock, struct msghdr *msg, struct alg_sock *pask = alg_sk(psk); struct af_alg_ctx *ctx = ask->private; struct crypto_aead *tfm = pask->private; - unsigned int i, as = crypto_aead_authsize(tfm); + unsigned int as = crypto_aead_authsize(tfm); struct af_alg_async_req *areq; - struct af_alg_tsgl *tsgl, *tmp; struct scatterlist *rsgl_src, *tsgl_src = NULL; int err = 0; size_t used = 0; /* [in] TX bufs to be en/decrypted */ @@ -154,23 +152,24 @@ static int _aead_recvmsg(struct socket *sock, struct msghdr *msg, outlen -= less; } + /* + * Create a per request TX SGL for this request which tracks the + * SG entries from the global TX SGL. + */ processed = used + ctx->aead_assoclen; - list_for_each_entry_safe(tsgl, tmp, &ctx->tsgl_list, list) { - for (i = 0; i < tsgl->cur; i++) { - struct scatterlist *process_sg = tsgl->sg + i; - - if (!(process_sg->length) || !sg_page(process_sg)) - continue; - tsgl_src = process_sg; - break; - } - if (tsgl_src) - break; - } - if (processed && !tsgl_src) { - err = -EFAULT; + areq->tsgl_entries = af_alg_count_tsgl(sk, processed); + if (!areq->tsgl_entries) + areq->tsgl_entries = 1; + areq->tsgl = sock_kmalloc(sk, array_size(sizeof(*areq->tsgl), + areq->tsgl_entries), + GFP_KERNEL); + if (!areq->tsgl) { + err = -ENOMEM; goto free; } + sg_init_table(areq->tsgl, areq->tsgl_entries); + af_alg_pull_tsgl(sk, processed, areq->tsgl); + tsgl_src = areq->tsgl; /* * Copy of AAD from source to destination @@ -179,75 +178,15 @@ static int _aead_recvmsg(struct socket *sock, struct msghdr *msg, * when user space uses an in-place cipher operation, the kernel * will copy the data as it does not see whether such in-place operation * is initiated. - * - * To ensure efficiency, the following implementation ensure that the - * ciphers are invoked to perform a crypto operation in-place. This - * is achieved by memory management specified as follows. */ /* Use the RX SGL as source (and destination) for crypto op. */ rsgl_src = areq->first_rsgl.sgl.sg; - if (ctx->enc) { - /* - * Encryption operation - The in-place cipher operation is - * achieved by the following operation: - * - * TX SGL: AAD || PT - * | | - * | copy | - * v v - * RX SGL: AAD || PT || Tag - */ - memcpy_sglist(areq->first_rsgl.sgl.sg, tsgl_src, processed); - af_alg_pull_tsgl(sk, processed, NULL, 0); - } else { - /* - * Decryption operation - To achieve an in-place cipher - * operation, the following SGL structure is used: - * - * TX SGL: AAD || CT || Tag - * | | ^ - * | copy | | Create SGL link. - * v v | - * RX SGL: AAD || CT ----+ - */ - - /* Copy AAD || CT to RX SGL buffer for in-place operation. */ - memcpy_sglist(areq->first_rsgl.sgl.sg, tsgl_src, outlen); - - /* Create TX SGL for tag and chain it to RX SGL. */ - areq->tsgl_entries = af_alg_count_tsgl(sk, processed, - processed - as); - if (!areq->tsgl_entries) - areq->tsgl_entries = 1; - areq->tsgl = sock_kmalloc(sk, array_size(sizeof(*areq->tsgl), - areq->tsgl_entries), - GFP_KERNEL); - if (!areq->tsgl) { - err = -ENOMEM; - goto free; - } - sg_init_table(areq->tsgl, areq->tsgl_entries); - - /* Release TX SGL, except for tag data and reassign tag data. */ - af_alg_pull_tsgl(sk, processed, areq->tsgl, processed - as); - - /* chain the areq TX SGL holding the tag with RX SGL */ - if (usedpages) { - /* RX SGL present */ - struct af_alg_sgl *sgl_prev = &areq->last_rsgl->sgl; - - sg_unmark_end(sgl_prev->sg + sgl_prev->npages - 1); - sg_chain(sgl_prev->sg, sgl_prev->npages + 1, - areq->tsgl); - } else - /* no RX SGL present (e.g. authentication only) */ - rsgl_src = areq->tsgl; - } + memcpy_sglist(rsgl_src, tsgl_src, ctx->aead_assoclen); /* Initialize the crypto operation */ - aead_request_set_crypt(&areq->cra_u.aead_req, rsgl_src, + aead_request_set_crypt(&areq->cra_u.aead_req, tsgl_src, areq->first_rsgl.sgl.sg, used, ctx->iv); aead_request_set_ad(&areq->cra_u.aead_req, ctx->aead_assoclen); aead_request_set_tfm(&areq->cra_u.aead_req, tfm); @@ -463,7 +402,7 @@ static void aead_sock_destruct(struct sock *sk) struct crypto_aead *tfm = pask->private; unsigned int ivlen = crypto_aead_ivsize(tfm); - af_alg_pull_tsgl(sk, ctx->used, NULL, 0); + af_alg_pull_tsgl(sk, ctx->used, NULL); sock_kzfree_s(sk, ctx->iv, ivlen); sock_kfree_s(sk, ctx, ctx->len); af_alg_release_parent(sk); diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c index bd9401e37706..edbdc19cdb31 100644 --- a/crypto/algif_skcipher.c +++ b/crypto/algif_skcipher.c @@ -95,7 +95,7 @@ static int _skcipher_recvmsg(struct socket *sock, struct msghdr *msg, * Create a per request TX SGL for this request which tracks the * SG entries from the global TX SGL. */ - areq->tsgl_entries = af_alg_count_tsgl(sk, len, 0); + areq->tsgl_entries = af_alg_count_tsgl(sk, len); if (!areq->tsgl_entries) areq->tsgl_entries = 1; areq->tsgl = sock_kmalloc(sk, array_size(sizeof(*areq->tsgl), @@ -106,7 +106,7 @@ static int _skcipher_recvmsg(struct socket *sock, struct msghdr *msg, goto free; } sg_init_table(areq->tsgl, areq->tsgl_entries); - af_alg_pull_tsgl(sk, len, areq->tsgl, 0); + af_alg_pull_tsgl(sk, len, areq->tsgl); /* Initialize the crypto operation */ skcipher_request_set_tfm(&areq->cra_u.skcipher_req, tfm); @@ -319,7 +319,7 @@ static void skcipher_sock_destruct(struct sock *sk) struct alg_sock *pask = alg_sk(psk); struct crypto_skcipher *tfm = pask->private; - af_alg_pull_tsgl(sk, ctx->used, NULL, 0); + af_alg_pull_tsgl(sk, ctx->used, NULL); sock_kzfree_s(sk, ctx->iv, crypto_skcipher_ivsize(tfm)); sock_kfree_s(sk, ctx, ctx->len); af_alg_release_parent(sk); diff --git a/include/crypto/if_alg.h b/include/crypto/if_alg.h index a406e281ae57..719a38d7e8bb 100644 --- a/include/crypto/if_alg.h +++ b/include/crypto/if_alg.h @@ -228,9 +228,8 @@ static inline bool af_alg_readable(struct sock *sk) return PAGE_SIZE <= af_alg_rcvbuf(sk); } -unsigned int af_alg_count_tsgl(struct sock *sk, size_t bytes, size_t offset); -void af_alg_pull_tsgl(struct sock *sk, size_t used, struct scatterlist *dst, - size_t dst_offset); +unsigned int af_alg_count_tsgl(struct sock *sk, size_t bytes); +void af_alg_pull_tsgl(struct sock *sk, size_t used, struct scatterlist *dst); void af_alg_wmem_wakeup(struct sock *sk); int af_alg_wait_for_data(struct sock *sk, unsigned flags, unsigned min); int af_alg_sendmsg(struct socket *sock, struct msghdr *msg, size_t size, -- 2.34.1