| From 26e64ca78ae844c5ceedde89531e2924d7d4594c Mon Sep 17 00:00:00 2001 |
| From: Chrostoper Ertl <chertl@microsoft.com> |
| Date: Thu, 28 Nov 2019 17:13:45 +0000 |
| Subject: [PATCH 5/5] fru, sdr: Fix id_string buffer overflows |
| |
| Final part of the fixes for CVE-2020-5208, see |
| https://github.com/ipmitool/ipmitool/security/advisories/GHSA-g659-9qxw-p7cp |
| |
| 9 variants of stack buffer overflow when parsing `id_string` field of |
| SDR records returned from `CMD_GET_SDR` command. |
| |
| SDR record structs have an `id_code` field, and an `id_string` `char` |
| array. |
| |
| The length of `id_string` is calculated as `(id_code & 0x1f) + 1`, |
| which can be larger than expected 16 characters (if `id_code = 0xff`, |
| then length will be `(0xff & 0x1f) + 1 = 32`). |
| |
| In numerous places, this can cause stack buffer overflow when copying |
| into fixed buffer of size `17` bytes from this calculated length. |
| |
| Upstream-Status: Backport[https://github.com/ipmitool/ipmitool/commit/7ccea283dd62a05a320c1921e3d8d71a87772637] |
| CVE: CVE-2020-5208 |
| |
| Signed-off-by: Wenlin Kang <wenlin.kang@windriver.com> |
| --- |
| lib/ipmi_fru.c | 2 +- |
| lib/ipmi_sdr.c | 40 ++++++++++++++++++++++++---------------- |
| 2 files changed, 25 insertions(+), 17 deletions(-) |
| |
| diff --git a/lib/ipmi_fru.c b/lib/ipmi_fru.c |
| index b71ea23..1decea2 100644 |
| --- a/lib/ipmi_fru.c |
| +++ b/lib/ipmi_fru.c |
| @@ -3038,7 +3038,7 @@ ipmi_fru_print(struct ipmi_intf * intf, struct sdr_record_fru_locator * fru) |
| return 0; |
| |
| memset(desc, 0, sizeof(desc)); |
| - memcpy(desc, fru->id_string, fru->id_code & 0x01f); |
| + memcpy(desc, fru->id_string, __min(fru->id_code & 0x01f, sizeof(desc))); |
| desc[fru->id_code & 0x01f] = 0; |
| printf("FRU Device Description : %s (ID %d)\n", desc, fru->device_id); |
| |
| diff --git a/lib/ipmi_sdr.c b/lib/ipmi_sdr.c |
| index fa7b082..175a86f 100644 |
| --- a/lib/ipmi_sdr.c |
| +++ b/lib/ipmi_sdr.c |
| @@ -2113,7 +2113,7 @@ ipmi_sdr_print_sensor_eventonly(struct ipmi_intf *intf, |
| return -1; |
| |
| memset(desc, 0, sizeof (desc)); |
| - snprintf(desc, (sensor->id_code & 0x1f) + 1, "%s", sensor->id_string); |
| + snprintf(desc, sizeof(desc), "%.*s", (sensor->id_code & 0x1f) + 1, sensor->id_string); |
| |
| if (verbose) { |
| printf("Sensor ID : %s (0x%x)\n", |
| @@ -2164,7 +2164,7 @@ ipmi_sdr_print_sensor_mc_locator(struct ipmi_intf *intf, |
| return -1; |
| |
| memset(desc, 0, sizeof (desc)); |
| - snprintf(desc, (mc->id_code & 0x1f) + 1, "%s", mc->id_string); |
| + snprintf(desc, sizeof(desc), "%.*s", (mc->id_code & 0x1f) + 1, mc->id_string); |
| |
| if (verbose == 0) { |
| if (csv_output) |
| @@ -2257,7 +2257,7 @@ ipmi_sdr_print_sensor_generic_locator(struct ipmi_intf *intf, |
| char desc[17]; |
| |
| memset(desc, 0, sizeof (desc)); |
| - snprintf(desc, (dev->id_code & 0x1f) + 1, "%s", dev->id_string); |
| + snprintf(desc, sizeof(desc), "%.*s", (dev->id_code & 0x1f) + 1, dev->id_string); |
| |
| if (!verbose) { |
| if (csv_output) |
| @@ -2314,7 +2314,7 @@ ipmi_sdr_print_sensor_fru_locator(struct ipmi_intf *intf, |
| char desc[17]; |
| |
| memset(desc, 0, sizeof (desc)); |
| - snprintf(desc, (fru->id_code & 0x1f) + 1, "%s", fru->id_string); |
| + snprintf(desc, sizeof(desc), "%.*s", (fru->id_code & 0x1f) + 1, fru->id_string); |
| |
| if (!verbose) { |
| if (csv_output) |
| @@ -2518,35 +2518,43 @@ ipmi_sdr_print_name_from_rawentry(struct ipmi_intf *intf,uint16_t id, |
| |
| int rc =0; |
| char desc[17]; |
| + const char *id_string; |
| + uint8_t id_code; |
| memset(desc, ' ', sizeof (desc)); |
| |
| switch ( type) { |
| case SDR_RECORD_TYPE_FULL_SENSOR: |
| record.full = (struct sdr_record_full_sensor *) raw; |
| - snprintf(desc, (record.full->id_code & 0x1f) +1, "%s", |
| - (const char *)record.full->id_string); |
| + id_code = record.full->id_code; |
| + id_string = record.full->id_string; |
| break; |
| + |
| case SDR_RECORD_TYPE_COMPACT_SENSOR: |
| record.compact = (struct sdr_record_compact_sensor *) raw ; |
| - snprintf(desc, (record.compact->id_code & 0x1f) +1, "%s", |
| - (const char *)record.compact->id_string); |
| + id_code = record.compact->id_code; |
| + id_string = record.compact->id_string; |
| break; |
| + |
| case SDR_RECORD_TYPE_EVENTONLY_SENSOR: |
| record.eventonly = (struct sdr_record_eventonly_sensor *) raw ; |
| - snprintf(desc, (record.eventonly->id_code & 0x1f) +1, "%s", |
| - (const char *)record.eventonly->id_string); |
| - break; |
| + id_code = record.eventonly->id_code; |
| + id_string = record.eventonly->id_string; |
| + break; |
| + |
| case SDR_RECORD_TYPE_MC_DEVICE_LOCATOR: |
| record.mcloc = (struct sdr_record_mc_locator *) raw ; |
| - snprintf(desc, (record.mcloc->id_code & 0x1f) +1, "%s", |
| - (const char *)record.mcloc->id_string); |
| + id_code = record.mcloc->id_code; |
| + id_string = record.mcloc->id_string; |
| break; |
| + |
| default: |
| rc = -1; |
| - break; |
| - } |
| + } |
| + if (!rc) { |
| + snprintf(desc, sizeof(desc), "%.*s", (id_code & 0x1f) + 1, id_string); |
| + } |
| |
| - lprintf(LOG_INFO, "ID: 0x%04x , NAME: %-16s", id, desc); |
| + lprintf(LOG_INFO, "ID: 0x%04x , NAME: %-16s", id, desc); |
| return rc; |
| } |
| |
| -- |
| 1.9.1 |
| |