From 8ca168c6f459d77cdf8f46d27a392d0847343703 Mon Sep 17 00:00:00 2001
From: Lukas Slebodnik <lslebodn@redhat.com>
Date: Thu, 16 Jul 2015 17:00:12 +0200
Subject: [PATCH 39/47] mmap_cache: "Override" functions for initgr mmap cache
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Functions sss_mc_get_strs_offset and sss_mc_get_strs_len provides
data about strings for individual memory caches (passwd, ...)
Their are used in generic responder mmap cache code to find a record
in mmap cache (sss_mc_find_record). Data provided from functions sss_mc_get_*
are used for checking the validity of record. So in case of corrupted record
the whole mmap cache can be invalidated.
Functions sss_mc_get_strs_offset and sss_mc_get_strs_len did not provide
data for initgroups mmap cache and therefore particular record could not be
invalidated.
Resolves:
https://fedorahosted.org/sssd/ticket/2716
Reviewed-by: Michal Židek <mzidek@redhat.com>
(cherry picked from commit 225dc6914cdc8920b02a129b98ece1ed97b99c03)
---
src/responder/nss/nsssrv_mmap_cache.c | 15 ++++++++++++---
src/sss_client/nss_mc_initgr.c | 16 +++++++++++-----
src/util/mmap_cache.h | 6 +++++-
3 files changed, 28 insertions(+), 9 deletions(-)
diff --git a/src/responder/nss/nsssrv_mmap_cache.c b/src/responder/nss/nsssrv_mmap_cache.c
index 16bc926f3ba4f5ab096bd0fb43895edef2b57c50..ab9e769b1f4d5d17a8c41429afce292298239bc5 100644
--- a/src/responder/nss/nsssrv_mmap_cache.c
+++ b/src/responder/nss/nsssrv_mmap_cache.c
@@ -475,6 +475,9 @@ static errno_t sss_mc_get_strs_offset(struct sss_mc_ctx *mcc,
case SSS_MC_GROUP:
*_offset = offsetof(struct sss_mc_grp_data, strs);
return EOK;
+ case SSS_MC_INITGROUPS:
+ *_offset = offsetof(struct sss_mc_initgr_data, gids);
+ return EOK;
default:
DEBUG(SSSDBG_FATAL_FAILURE, "Unknown memory cache type.\n");
return EINVAL;
@@ -492,6 +495,9 @@ static errno_t sss_mc_get_strs_len(struct sss_mc_ctx *mcc,
case SSS_MC_GROUP:
*_len = ((struct sss_mc_grp_data *)&rec->data)->strs_len;
return EOK;
+ case SSS_MC_INITGROUPS:
+ *_len = ((struct sss_mc_initgr_data *)&rec->data)->data_len;
+ return EOK;
default:
DEBUG(SSSDBG_FATAL_FAILURE, "Unknown memory cache type.\n");
return EINVAL;
@@ -974,8 +980,8 @@ errno_t sss_mmap_cache_initgr_store(struct sss_mc_ctx **_mcc,
return EINVAL;
}
- /* num_groups + reserved + array of gids + name*/
- data_len = (2 + num_groups) * sizeof(uint32_t) + name->len;
+ /* array of gids + name */
+ data_len = num_groups * sizeof(uint32_t) + name->len;
rec_len = sizeof(struct sss_mc_rec) + sizeof(struct sss_mc_initgr_data)
+ data_len;
if (rec_len > mcc->dt_size) {
@@ -998,10 +1004,13 @@ errno_t sss_mmap_cache_initgr_store(struct sss_mc_ctx **_mcc,
name->str, name->len, name->str, name->len);
/* initgroups struct */
+ data->strs_len = name->len;
+ data->data_len = data_len;
+ data->reserved = MC_INVALID_VAL32;
data->num_groups = num_groups;
memcpy(data->gids, gids_buf, num_groups * sizeof(uint32_t));
memcpy(&data->gids[num_groups], name->str, name->len);
- data->name = MC_PTR_DIFF(&data->gids[num_groups], data);
+ data->strs = data->name = MC_PTR_DIFF(&data->gids[num_groups], data);
MC_LOWER_BARRIER(rec);
diff --git a/src/sss_client/nss_mc_initgr.c b/src/sss_client/nss_mc_initgr.c
index e21b9f40aba00f9cc2385a561fc2bcc163c5791a..153617ea9c6489b7439b9676904b42b042f6697c 100644
--- a/src/sss_client/nss_mc_initgr.c
+++ b/src/sss_client/nss_mc_initgr.c
@@ -93,6 +93,7 @@ errno_t sss_nss_mc_initgroups_dyn(const char *name, size_t name_len,
uint32_t hash;
uint32_t slot;
int ret;
+ const size_t data_offset = offsetof(struct sss_mc_initgr_data, gids);
uint8_t *max_addr;
ret = sss_nss_mc_get_ctx("initgroups", &initgr_mc_ctx);
@@ -128,16 +129,21 @@ errno_t sss_nss_mc_initgroups_dyn(const char *name, size_t name_len,
}
data = (struct sss_mc_initgr_data *)rec->data;
+ rec_name = (char *)data + data->name;
/* Integrity check
- * - array with gids must be within data_table
- * - string must be within data_table */
- if ((uint8_t *)data->gids > max_addr
- || (uint8_t *)data + data->name + name_len > max_addr) {
+ * - name_len cannot be longer than all strings or data
+ * - data->name cannot point outside strings
+ * - all data must be within data_table
+ * - name must be within data_table */
+ if (name_len > data->data_len
+ || name_len > data->strs_len
+ || (data->strs + name_len) > (data_offset + data->data_len)
+ || (uint8_t *)data->gids + data->data_len > max_addr
+ || (uint8_t *)rec_name + name_len > max_addr) {
ret = ENOENT;
goto done;
}
- rec_name = (char *)data + data->name;
if (strcmp(name, rec_name) == 0) {
break;
}
diff --git a/src/util/mmap_cache.h b/src/util/mmap_cache.h
index a8703d5da4022e11c4bc2f3e2f8710e7f9d982bf..b5917b3c0973276e43e9fe160cec7528b1224f8f 100644
--- a/src/util/mmap_cache.h
+++ b/src/util/mmap_cache.h
@@ -79,7 +79,7 @@ typedef uint32_t rel_ptr_t;
#define SSS_MC_MAJOR_VNO 1
-#define SSS_MC_MINOR_VNO 0
+#define SSS_MC_MINOR_VNO 1
#define SSS_MC_HEADER_UNINIT 0 /* after ftruncate or before reset */
#define SSS_MC_HEADER_ALIVE 1 /* current and in use */
@@ -139,6 +139,10 @@ struct sss_mc_grp_data {
struct sss_mc_initgr_data {
rel_ptr_t name; /* ptr to name string, rel. to struct base addr */
+ rel_ptr_t strs; /* ptr to concatenation of all strings */
+ uint32_t reserved;
+ uint32_t strs_len; /* length of strs */
+ uint32_t data_len; /* all initgroups data len */
uint32_t num_groups; /* number of groups */
uint32_t gids[0]; /* array of all groups
* string with name is stored after gids */
--
2.4.3