On (16/07/15 17:07), Lukas Slebodnik wrote:
On (16/07/15 13:46), Michal Židek wrote:
>On 07/15/2015 06:42 PM, Lukas Slebodnik wrote:
>>ehlo,
>>
>>reproducer:
>> add user and few groups to ldap
>> call id user
>> remove one group
>> authenticate
>> call id user // removed groups should not appear in output
>>
>>LS
>>
>>
>>0001-mmap_cache-Override-functions-for-initgr-mmap-cache.patch
>>
>>
>> From 146337d5a3a15236b0a8c26e10d233e8cbc3a1d8 Mon Sep 17 00:00:00 2001
>>From: Lukas Slebodnik<lslebodn(a)redhat.com>
>>Date: Wed, 15 Jul 2015 17:47:29 +0200
>>Subject: [PATCH] mmap_cache: "Override" functions for initgr mmap cache
>>
>>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
>>---
>> 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
ebda8ac6fab3dd87f5a1d8e43717bf7a5b5a9878..6251ff93ce7f8bf473fc770f7aa3d2e0642395a3 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;
>> }
>>
>>- /* memnum + reserved + array of members + name*/
>>- data_len = (2 + memnum) * sizeof(uint32_t) + name->len;
>>+ /* array of members + name */
>>+ data_len = memnum * sizeof(uint32_t) + name->len;
>
>It is actually not array of members but array of group ids
>the user is member of. It would be good to rename the
>memnum to num_groups or something similiar.
>
>> 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->members = memnum;
> ^^^^^^^^^^^^^ ^^^^^^
>Same as above.
>
>> memcpy(data->gids, membuf, memnum * sizeof(uint32_t));
> ^^^^^^ ^^^^^^
>gids_buf
>
>> memcpy(&data->gids[memnum], name->str, name->len);
>>- data->name = MC_PTR_DIFF(&data->gids[memnum], data);
> ^^^^^^
>>+ data->strs = data->name = MC_PTR_DIFF(&data->gids[memnum],
data);
>>
>> MC_LOWER_BARRIER(rec);
>>
>>diff --git a/src/sss_client/nss_mc_initgr.c b/src/sss_client/nss_mc_initgr.c
>>index
bfb09d6550c310fbab254dc9b3ab7b306b7d3f06..0ccde2130526786e1949287cde1e4c1bc4596670 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->name + 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
438e28a3d217041278fc1bb60aa553d098516035..6cd1e46218fc2a814b34200f0837ee7fff382378 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 */
> ^^^^^^^^^^^^^^
>This pointer is not needed. The name pointer is enough.
>
>>+ uint32_t strs_len; /* length of strs */
> ^^^^^^^^
>This should be called name_len.
>
>>+ uint32_t data_len; /* all initgroups data len */
>>+ uint32_t reserved;
>> uint32_t members; /* number of members in groups */
> ^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^^
>Again not members, number of gids.
>
>> uint32_t gids[0]; /* array of all groups
>> * string with name is stored after gids */
>>-- 2.4.3
>
>
>If you do not want to squash the renaming into the same patch, feel free
>to attach it as separate patch.
Yes, they need to be in separate patch because they are not related
to the regression.
> I am fine either way. Sorry I should
>have catch this in the first iteration of the initgr memcache patches.
>
I glad the biggest issue in patches was just variable names.
LS
From e6f0d72167fdd6921e173025a0e374996fc156d5 Mon Sep 17 00:00:00
2001
From: Lukas Slebodnik <lslebodn(a)redhat.com>
Date: Thu, 16 Jul 2015 16:54:00 +0200
Subject: [PATCH 1/2] mmap_cache: Rename variables
---
self-NACK
There is a crash in nss responder
Thread 1 (Thread 0x7f43151a8700 (LWP 30847)):
#0 0x00007f431058a174 in __strcmp_sse2 () from /lib64/libc.so.6
No symbol table info available.
#1 0x000000000041768b in sss_mc_find_record (mcc=0x113ee90, key=0x7ffce089a5b0) at
+src/responder/nss/nsssrv_mmap_cache.c:562
rec = 0x7f4306f2b038
hash = 13194
slot = <value optimized out>
name_ptr = <value optimized out>
t_key = <value optimized out>
strs_offset = 24
strs_len = <value optimized out>
max_addr = 0x7f43076cc238 <Address 0x7f43076cc238 out of bounds>
ret = 0
__FUNCTION__ = "sss_mc_find_record"
LS