From: Michael Bommarito <michael.bommarito@gmail.com> mainline inclusion from mainline-v7.2-rc1 commit bf33e01f88388c43e285492a63e539df6ffed64c category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/16215 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- iscsi_encode_text_output() concatenates "key=value\0" records into login->rsp_buf, an 8192-byte kzalloc(MAX_KEY_VALUE_PAIRS) buffer allocated in iscsit_alloc_login_setup_buffer(). The three sprintf() call sites in this function (lines 1398, 1411, 1424 in v7.1-rc2) never check the remaining buffer capacity: *length += sprintf(output_buf, "%s=%s", er->key, er->value); *length += 1; output_buf = textbuf + *length; The 8192-byte ceiling at iscsi_target_check_login_request() bounds the *input* Login PDU payload, but a single PDU can carry up to 2048 minimal four-byte "a=b\0" pairs, each unknown key expanding to a 16-byte "a=NotUnderstood\0" output record via iscsi_add_notunderstood_response(). 2048 * 16 = 32 KiB of output into an 8 KiB buffer, producing a ~24 KiB heap overrun in the kmalloc-8k slab. The fix introduces a static iscsi_encode_text_record() helper that uses snprintf() with a per-call bounds check against the remaining buffer, and threads a u32 textbuf_size parameter through iscsi_encode_text_output(). Both call sites in iscsi_target_handle_csg_zero() (PHASE_SECURITY) and iscsi_target_handle_csg_one() (PHASE_OPERATIONAL) pass MAX_KEY_VALUE_PAIRS. On overflow the encoder logs the condition, calls iscsi_release_extra_responses() to drop queued records, and returns -1; both caller sites now emit ISCSI_STATUS_CLS_INITIATOR_ERR / ISCSI_LOGIN_STATUS_INIT_ERR via iscsit_tx_login_rsp() before returning, so the initiator sees an explicit failed-login response rather than a silent connection drop. (Prior to this patch only the PHASE_OPERATIONAL caller did that; the PHASE_SECURITY caller is converted to the same shape.) Fixes: e48354ce078c ("iscsi-target: Add iSCSI fabric support for target v4.1") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com> Tested-by: John Garry <john.g.garry@oracle.com> Reviewed-by: John Garry <john.g.garry@oracle.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Lu Chentao <luchentao1@huawei.com> --- drivers/target/iscsi/iscsi_target_nego.c | 7 ++- .../target/iscsi/iscsi_target_parameters.c | 62 ++++++++++++++----- .../target/iscsi/iscsi_target_parameters.h | 2 +- 3 files changed, 55 insertions(+), 16 deletions(-) diff --git a/drivers/target/iscsi/iscsi_target_nego.c b/drivers/target/iscsi/iscsi_target_nego.c index fa3fb5f4e6bc..f98734524693 100644 --- a/drivers/target/iscsi/iscsi_target_nego.c +++ b/drivers/target/iscsi/iscsi_target_nego.c @@ -897,14 +897,18 @@ static int iscsi_target_handle_csg_zero( ret = iscsi_encode_text_output( PHASE_SECURITY|PHASE_DECLARATIVE, SENDER_TARGET, login->rsp_buf, &login->rsp_length, + MAX_KEY_VALUE_PAIRS, conn->param_list, conn->tpg->tpg_attrib.login_keys_workaround); - if (ret < 0) + if (ret < 0) { + iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR, + ISCSI_LOGIN_STATUS_INIT_ERR); return -1; + } if (!iscsi_check_negotiated_keys(conn->param_list)) { bool auth_required = iscsi_conn_auth_required(conn); if (auth_required) { @@ -984,10 +988,11 @@ static int iscsi_target_handle_csg_one(struct iscsit_conn *conn, struct iscsi_lo ret = iscsi_encode_text_output( PHASE_OPERATIONAL|PHASE_DECLARATIVE, SENDER_TARGET, login->rsp_buf, &login->rsp_length, + MAX_KEY_VALUE_PAIRS, conn->param_list, conn->tpg->tpg_attrib.login_keys_workaround); if (ret < 0) { iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR, ISCSI_LOGIN_STATUS_INIT_ERR); diff --git a/drivers/target/iscsi/iscsi_target_parameters.c b/drivers/target/iscsi/iscsi_target_parameters.c index 5b90c22ee3dc..5e15c2ea7d65 100644 --- a/drivers/target/iscsi/iscsi_target_parameters.c +++ b/drivers/target/iscsi/iscsi_target_parameters.c @@ -1417,23 +1417,46 @@ int iscsi_decode_text_input( free_buffer: kfree(tmpbuf); return -1; } +/* + * Append "key=value" plus a trailing NUL into @textbuf at *@length. + * Returns 0 on success and advances *@length, or -EMSGSIZE if the + * record (including the NUL) would not fit in the remaining buffer. + */ +static int iscsi_encode_text_record(char *textbuf, u32 *length, + u32 textbuf_size, + const char *key, const char *value) +{ + int n; + u32 avail; + + if (*length >= textbuf_size) + return -EMSGSIZE; + + avail = textbuf_size - *length; + n = snprintf(textbuf + *length, avail, "%s=%s", key, value); + if (n < 0 || (u32)n + 1 > avail) + return -EMSGSIZE; + + *length += n + 1; + return 0; +} + int iscsi_encode_text_output( u8 phase, u8 sender, char *textbuf, u32 *length, + u32 textbuf_size, struct iscsi_param_list *param_list, bool keys_workaround) { - char *output_buf = NULL; struct iscsi_extra_response *er; struct iscsi_param *param; - - output_buf = textbuf + *length; + int ret; if (iscsi_enforce_integrity_rules(phase, param_list) < 0) return -1; list_for_each_entry(param, ¶m_list->param_list, p_list) { @@ -1441,44 +1464,55 @@ int iscsi_encode_text_output( continue; if (IS_PSTATE_ACCEPTOR(param) && !IS_PSTATE_RESPONSE_SENT(param) && !IS_PSTATE_REPLY_OPTIONAL(param) && (param->phase & phase)) { - *length += sprintf(output_buf, "%s=%s", - param->name, param->value); - *length += 1; - output_buf = textbuf + *length; + ret = iscsi_encode_text_record(textbuf, length, + textbuf_size, + param->name, + param->value); + if (ret < 0) + goto err_overflow; SET_PSTATE_RESPONSE_SENT(param); pr_debug("Sending key: %s=%s\n", param->name, param->value); continue; } if (IS_PSTATE_NEGOTIATE(param) && !IS_PSTATE_ACCEPTOR(param) && !IS_PSTATE_PROPOSER(param) && (param->phase & phase)) { - *length += sprintf(output_buf, "%s=%s", - param->name, param->value); - *length += 1; - output_buf = textbuf + *length; + ret = iscsi_encode_text_record(textbuf, length, + textbuf_size, + param->name, + param->value); + if (ret < 0) + goto err_overflow; SET_PSTATE_PROPOSER(param); iscsi_check_proposer_for_optional_reply(param, keys_workaround); pr_debug("Sending key: %s=%s\n", param->name, param->value); } } list_for_each_entry(er, ¶m_list->extra_response_list, er_list) { - *length += sprintf(output_buf, "%s=%s", er->key, er->value); - *length += 1; - output_buf = textbuf + *length; + ret = iscsi_encode_text_record(textbuf, length, textbuf_size, + er->key, er->value); + if (ret < 0) + goto err_overflow; pr_debug("Sending key: %s=%s\n", er->key, er->value); } iscsi_release_extra_responses(param_list); return 0; + +err_overflow: + pr_err("iSCSI login response buffer (%u bytes) exhausted, dropping login.\n", + textbuf_size); + iscsi_release_extra_responses(param_list); + return -1; } int iscsi_check_negotiated_keys(struct iscsi_param_list *param_list) { int ret = 0; diff --git a/drivers/target/iscsi/iscsi_target_parameters.h b/drivers/target/iscsi/iscsi_target_parameters.h index 00fbbebb8c75..d6cbe5dd4b00 100644 --- a/drivers/target/iscsi/iscsi_target_parameters.h +++ b/drivers/target/iscsi/iscsi_target_parameters.h @@ -44,11 +44,11 @@ extern int iscsi_change_param_value(char *, struct iscsi_param_list *, int); extern void iscsi_release_param_list(struct iscsi_param_list *); extern struct iscsi_param *iscsi_find_param_from_key(char *, struct iscsi_param_list *); extern int iscsi_extract_key_value(char *, char **, char **); extern int iscsi_update_param_value(struct iscsi_param *, char *); extern int iscsi_decode_text_input(u8, u8, char *, u32, struct iscsit_conn *); -extern int iscsi_encode_text_output(u8, u8, char *, u32 *, +extern int iscsi_encode_text_output(u8, u8, char *, u32 *, u32, struct iscsi_param_list *, bool); extern int iscsi_check_negotiated_keys(struct iscsi_param_list *); extern void iscsi_set_connection_parameters(struct iscsi_conn_ops *, struct iscsi_param_list *); extern void iscsi_set_session_parameters(struct iscsi_sess_ops *, -- 2.52.0

From: Michael Bommarito <michael.bommarito@gmail.com> stable inclusion from stable-v6.6.143 commit d3e9b79aa794f7a23e82de4d710e7d2df610e349 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/16216 CVE: CVE-2026-63888 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 778c2ab142c625a8a8afa570e0f9b7873f445d99 ] Two latent bugs in the Text-phase handler, both present since the original LIO integration in commit e48354ce078c ("iscsi-target: Add iSCSI fabric support for target v4.1"): 1) DataDigest CRC buffer overread (4 bytes past text_in). text_in is kzalloc()'d at ALIGN(payload_length, 4). rx_size is then incremented by ISCSI_CRC_LEN to make room for the received DataDigest in the iovec, but the same (now-bumped) rx_size is passed as the buffer length to iscsit_crc_buf(): if (conn->conn_ops->DataDigest) { ... rx_size += ISCSI_CRC_LEN; } ... if (conn->conn_ops->DataDigest) { data_crc = iscsit_crc_buf(text_in, rx_size, 0, NULL); iscsit_crc_buf() walks rx_size bytes of text_in with crc32c(), so when DataDigest is negotiated it reads 4 bytes past the end of the text_in allocation. KASAN reproduces this directly on the unpatched mainline tree as slab-out-of-bounds in crc32c() called from the Text PDU path. The OOB bytes feed crc32c() and are then compared against the initiator-supplied checksum, so the value does not flow back to the attacker, but the kernel does read past the buffer on every Text PDU with DataDigest=CRC32C. Fix by passing the actual padded payload length (ALIGN(payload_length, 4)) that was used for the kzalloc(). 2) Stale cmd->text_in_ptr re-free (double-free) on ERL>0 bad DataDigest drop. On DataDigest mismatch with ErrorRecoveryLevel > 0 the handler silently drops the PDU and lets the initiator plug the CmdSN gap: kfree(text_in); return 0; cmd->text_in_ptr still points at the freed buffer. The next Text Request on the same ITT re-enters iscsit_setup_text_cmd(), which unconditionally does kfree(cmd->text_in_ptr); cmd->text_in_ptr = NULL; freeing the same pointer a second time. Session teardown via iscsit_release_cmd() has the same shape and hits the same double-free if the connection is dropped before a second Text Request arrives. On an unmodified mainline tree the bug-1 CRC overread fires first on the initial valid Text Request and perturbs the subsequent state, so #4 was isolated by building a kernel with only the bug-1 hunk of this patch applied plus temporary printk() observability around the three relevant kfree() sites. The observability prints are not part of this patch. On that build, a three-PDU Text Request sequence after login produces two back-to-back splats: BUG: KASAN: double-free in iscsit_setup_text_cmd+0x?? BUG: KASAN: double-free in iscsit_release_cmd+0x?? showing the same pointer freed in the ERL>0 drop path and again in iscsit_setup_text_cmd() (next Text Request on the same ITT) and once more in iscsit_release_cmd() (session teardown). On distro kernels with CONFIG_SLAB_FREELIST_HARDENED=y (default) the double-free becomes a remote kernel BUG(); on non-hardened kernels it corrupts the slab freelist. Fix by clearing cmd->text_in_ptr after the kfree() in the ERL>0 drop path. With both hunks applied #4 is directly observable on the stock tree without observability printks; fixing bug-1 alone would mask #4 less, not more, so the hunks are submitted together. Both fixes are one-liners. The Text PDU state machine is unchanged and the wire protocol is unaffected. Fixes: e48354ce078c ("iscsi-target: Add iSCSI fabric support for target v4.1") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com> Tested-by: John Garry <john.g.garry@oracle.com> Reviewed-by: John Garry <john.g.garry@oracle.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Lu Chentao <luchentao1@huawei.com> --- drivers/target/iscsi/iscsi_target.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c index b756d4cfecfe..5cad08685350 100644 --- a/drivers/target/iscsi/iscsi_target.c +++ b/drivers/target/iscsi/iscsi_target.c @@ -2333,12 +2333,13 @@ iscsit_handle_text_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd, if (rx_got != rx_size) goto reject; if (conn->conn_ops->DataDigest) { iscsit_do_crypto_hash_buf(conn->conn_rx_hash, - text_in, rx_size, 0, NULL, - &data_crc); + text_in, + ALIGN(payload_length, 4), + 0, NULL, &data_crc); if (checksum != data_crc) { pr_err("Text data CRC32C DataDigest" " 0x%08x does not match computed" " 0x%08x\n", checksum, data_crc); @@ -2354,10 +2355,11 @@ iscsit_handle_text_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd, */ pr_debug("Dropping Text" " Command CmdSN: 0x%08x due to" " DataCRC error.\n", hdr->cmdsn); kfree(text_in); + cmd->text_in_ptr = NULL; return 0; } } else { pr_debug("Got CRC32C DataDigest" " 0x%08x for %u bytes of text data.\n", -- 2.52.0

From: Alexandru Hossu <hossu.alexandru@gmail.com> mainline inclusion from mainline-v7.1 commit 85db7391310b1304d2dc8ae3b0b12105a9567147 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/16519 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- chap_server_compute_hash() allocates client_digest as kzalloc(chap->digest_size) and then, for BASE64-encoded responses, passes chap_r directly to chap_base64_decode() without checking whether the input length could produce more than digest_size bytes of output. chap_base64_decode() writes to the destination unconditionally as long as there is input to consume. With MAX_RESPONSE_LENGTH set to 128 and the "0b" prefix stripped by extract_param(), up to 127 base64 characters can reach the decoder. 127 characters decode to 95 bytes. For SHA-256 (digest_size=32) this overflows client_digest by 63 bytes; for MD5 (digest_size=16) the overflow is 79 bytes. The length check at line 344 fires after the write has already happened. The HEX branch in the same switch statement already validates the length up front. Apply the same approach to the BASE64 branch: strip trailing base64 padding characters, then reject any input whose data length exceeds DIV_ROUND_UP(digest_size * 4, 3) before calling the decoder. Stripping trailing '=' before the comparison handles both padded and unpadded encodings. chap_base64_decode() already returns early on '=', so the full original string is still passed to the decoder unchanged. The mutual CHAP path decodes CHAP_C into initiatorchg_binhex, which is kzalloc(CHAP_CHALLENGE_STR_LEN). extract_param() caps initiatorchg at CHAP_CHALLENGE_STR_LEN characters, so at most CHAP_CHALLENGE_STR_LEN-1 base64 characters reach the decoder. The maximum decoded size, DIV_ROUND_UP((CHAP_CHALLENGE_STR_LEN-1) * 3, 4), is less than CHAP_CHALLENGE_STR_LEN, so no overflow is possible there. A comment is added at the call site to document this. Fixes: 1e5733883421 ("scsi: target: iscsi: Support base64 in CHAP") Cc: stable@vger.kernel.org Signed-off-by: Alexandru Hossu <hossu.alexandru@gmail.com> Reviewed-by: David Disseldorp <ddiss@suse.de> Link: https://patch.msgid.link/20260521151121.808477-1-hossu.alexandru@gmail.com Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Lu Chentao <luchentao1@huawei.com> --- drivers/target/iscsi/iscsi_target_auth.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/drivers/target/iscsi/iscsi_target_auth.c b/drivers/target/iscsi/iscsi_target_auth.c index c8a248bd11be..02a4c9aff98d 100644 --- a/drivers/target/iscsi/iscsi_target_auth.c +++ b/drivers/target/iscsi/iscsi_target_auth.c @@ -337,17 +337,26 @@ static int chap_server_compute_hash( if (hex2bin(client_digest, chap_r, chap->digest_size) < 0) { pr_err("Malformed CHAP_R: invalid HEX\n"); goto out; } break; - case BASE64: + case BASE64: { + size_t r_len = strlen(chap_r); + + while (r_len > 0 && chap_r[r_len - 1] == '=') + r_len--; + if (r_len > DIV_ROUND_UP(chap->digest_size * 4, 3)) { + pr_err("Malformed CHAP_R: base64 payload too long\n"); + goto out; + } if (chap_base64_decode(client_digest, chap_r, strlen(chap_r)) != chap->digest_size) { pr_err("Malformed CHAP_R: invalid BASE64\n"); goto out; } break; + } default: pr_err("Could not find CHAP_R\n"); goto out; } @@ -470,10 +479,18 @@ static int chap_server_compute_hash( pr_err("Malformed CHAP_C: invalid HEX\n"); goto out; } break; case BASE64: + /* + * No overflow check needed: initiatorchg_binhex is + * CHAP_CHALLENGE_STR_LEN bytes and extract_param() caps + * initiatorchg at CHAP_CHALLENGE_STR_LEN characters, so + * the decoded output is at most DIV_ROUND_UP( + * (CHAP_CHALLENGE_STR_LEN - 1) * 3, 4) bytes, which is + * less than CHAP_CHALLENGE_STR_LEN. + */ initiatorchg_len = chap_base64_decode(initiatorchg_binhex, initiatorchg, strlen(initiatorchg)); if (initiatorchg_len < 0) { pr_err("Malformed CHAP_C: invalid BASE64\n"); -- 2.52.0