From 13df7b9e400211c717284fb841c849ba034ed348 Mon Sep 17 00:00:00 2001
From: Michal Zidek <mzidek@redhat.com>
Date: Wed, 14 Aug 2013 18:22:06 +0200
Subject: [PATCH 3/4] mmap_cache: Off by one error.
Removes off by one error when using macro MC_SIZE_TO_SLOTS
and adds new macro MC_SLOT_WITHIN_BOUNDS.
---
src/responder/nss/nsssrv_mmap_cache.c | 12 ++++++------
src/sss_client/nss_mc_group.c | 8 ++++----
src/sss_client/nss_mc_passwd.c | 8 ++++----
src/util/mmap_cache.h | 3 +++
4 files changed, 17 insertions(+), 14 deletions(-)
diff --git a/src/responder/nss/nsssrv_mmap_cache.c b/src/responder/nss/nsssrv_mmap_cache.c
index cd5a6436e005b4c7f5622eaff2f259de3bbe5d29..a1bab0c8d877a354451ad5c31ec5e86b294837e9 100644
--- a/src/responder/nss/nsssrv_mmap_cache.c
+++ b/src/responder/nss/nsssrv_mmap_cache.c
@@ -368,12 +368,12 @@ static struct sss_mc_rec *sss_mc_find_record(struct sss_mc_ctx *mcc,
hash = sss_mc_hash(mcc, key->str, key->len);
slot = mcc->hash_table[hash];
- if (slot > MC_SIZE_TO_SLOTS(mcc->dt_size)) {
+ if (!MC_SLOT_WITHIN_BOUNDS(slot, mcc->dt_size)) {
return NULL;
}
while (slot != MC_INVALID_VAL) {
- if (slot > MC_SIZE_TO_SLOTS(mcc->dt_size)) {
+ if (!MC_SLOT_WITHIN_BOUNDS(slot, mcc->dt_size)) {
DEBUG(SSSDBG_FATAL_FAILURE,
("Corrupted fastcache. Slot number too big.\n"));
sss_mmap_cache_reset(mcc);
@@ -617,13 +617,13 @@ errno_t sss_mmap_cache_pw_invalidate_uid(struct sss_mc_ctx *mcc, uid_t uid)
hash = sss_mc_hash(mcc, uidstr, strlen(uidstr) + 1);
slot = mcc->hash_table[hash];
- if (slot > MC_SIZE_TO_SLOTS(mcc->dt_size)) {
+ if (!MC_SLOT_WITHIN_BOUNDS(slot, mcc->dt_size)) {
ret = ENOENT;
goto done;
}
while (slot != MC_INVALID_VAL) {
- if (slot > MC_SIZE_TO_SLOTS(mcc->dt_size)) {
+ if (!MC_SLOT_WITHIN_BOUNDS(slot, mcc->dt_size)) {
DEBUG(SSSDBG_FATAL_FAILURE, ("Corrupted fastcache.\n"));
sss_mmap_cache_reset(mcc);
ret = ENOENT;
@@ -755,13 +755,13 @@ errno_t sss_mmap_cache_gr_invalidate_gid(struct sss_mc_ctx *mcc, gid_t gid)
hash = sss_mc_hash(mcc, gidstr, strlen(gidstr) + 1);
slot = mcc->hash_table[hash];
- if (slot > MC_SIZE_TO_SLOTS(mcc->dt_size)) {
+ if (!MC_SLOT_WITHIN_BOUNDS(slot, mcc->dt_size)) {
ret = ENOENT;
goto done;
}
while (slot != MC_INVALID_VAL) {
- if (slot > MC_SIZE_TO_SLOTS(mcc->dt_size)) {
+ if (!MC_SLOT_WITHIN_BOUNDS(slot, mcc->dt_size)) {
DEBUG(SSSDBG_FATAL_FAILURE, ("Corrupted fastcache.\n"));
sss_mmap_cache_reset(mcc);
ret = ENOENT;
diff --git a/src/sss_client/nss_mc_group.c b/src/sss_client/nss_mc_group.c
index 9fe72a60e58e0c94f0c38f243276060b70f28aa9..4e3d9fb0dfffc2194a6d1e2035ed5782af528fce 100644
--- a/src/sss_client/nss_mc_group.c
+++ b/src/sss_client/nss_mc_group.c
@@ -121,7 +121,7 @@ errno_t sss_nss_mc_getgrnam(const char *name, size_t name_len,
/* If slot is not within the bounds of mmaped region and
* it's value is not MC_INVALID_VAL, then the cache is
* probbably corrupted. */
- while (slot < MC_SIZE_TO_SLOTS(gr_mc_ctx.dt_size)) {
+ while (MC_SLOT_WITHIN_BOUNDS(slot, gr_mc_ctx.dt_size)) {
ret = sss_nss_mc_get_record(&gr_mc_ctx, slot, &rec);
if (ret) {
goto done;
@@ -155,7 +155,7 @@ errno_t sss_nss_mc_getgrnam(const char *name, size_t name_len,
slot = rec->next;
}
- if (slot >= MC_SIZE_TO_SLOTS(gr_mc_ctx.dt_size)) {
+ if (!MC_SLOT_WITHIN_BOUNDS(slot, gr_mc_ctx.dt_size)) {
ret = ENOENT;
goto done;
}
@@ -196,7 +196,7 @@ errno_t sss_nss_mc_getgrgid(gid_t gid,
/* If slot is not within the bounds of mmaped region and
* it's value is not MC_INVALID_VAL, then the cache is
* probbably corrupted. */
- while (slot < MC_SIZE_TO_SLOTS(gr_mc_ctx.dt_size)) {
+ while (MC_SLOT_WITHIN_BOUNDS(slot, gr_mc_ctx.dt_size)) {
ret = sss_nss_mc_get_record(&gr_mc_ctx, slot, &rec);
if (ret) {
goto done;
@@ -217,7 +217,7 @@ errno_t sss_nss_mc_getgrgid(gid_t gid,
slot = rec->next;
}
- if (slot >= MC_SIZE_TO_SLOTS(gr_mc_ctx.dt_size)) {
+ if (!MC_SLOT_WITHIN_BOUNDS(slot, gr_mc_ctx.dt_size)) {
ret = ENOENT;
goto done;
}
diff --git a/src/sss_client/nss_mc_passwd.c b/src/sss_client/nss_mc_passwd.c
index 7aca4a04b6b19b50b883960229083b688639ee4f..a0a8d87f7475d8fea1bc32409a2d5c6af8f7896f 100644
--- a/src/sss_client/nss_mc_passwd.c
+++ b/src/sss_client/nss_mc_passwd.c
@@ -122,7 +122,7 @@ errno_t sss_nss_mc_getpwnam(const char *name, size_t name_len,
/* If slot is not within the bounds of mmaped region and
* it's value is not MC_INVALID_VAL, then the cache is
* probbably corrupted. */
- while (slot < MC_SIZE_TO_SLOTS(pw_mc_ctx.dt_size)) {
+ while (MC_SLOT_WITHIN_BOUNDS(slot, pw_mc_ctx.dt_size)) {
ret = sss_nss_mc_get_record(&pw_mc_ctx, slot, &rec);
if (ret) {
goto done;
@@ -157,7 +157,7 @@ errno_t sss_nss_mc_getpwnam(const char *name, size_t name_len,
slot = rec->next;
}
- if (slot >= MC_SIZE_TO_SLOTS(pw_mc_ctx.dt_size)) {
+ if (!MC_SLOT_WITHIN_BOUNDS(slot, pw_mc_ctx.dt_size)) {
ret = ENOENT;
goto done;
}
@@ -198,7 +198,7 @@ errno_t sss_nss_mc_getpwuid(uid_t uid,
/* If slot is not within the bounds of mmaped region and
* it's value is not MC_INVALID_VAL, then the cache is
* probbably corrupted. */
- while (slot < MC_SIZE_TO_SLOTS(pw_mc_ctx.dt_size)) {
+ while (MC_SLOT_WITHIN_BOUNDS(slot, pw_mc_ctx.dt_size)) {
ret = sss_nss_mc_get_record(&pw_mc_ctx, slot, &rec);
if (ret) {
goto done;
@@ -219,7 +219,7 @@ errno_t sss_nss_mc_getpwuid(uid_t uid,
slot = rec->next;
}
- if (slot >= MC_SIZE_TO_SLOTS(pw_mc_ctx.dt_size)) {
+ if (!MC_SLOT_WITHIN_BOUNDS(slot, pw_mc_ctx.dt_size)) {
ret = ENOENT;
goto done;
}
diff --git a/src/util/mmap_cache.h b/src/util/mmap_cache.h
index 6c223df6c79b5ac10786903eecd1cb8c8a3999a5..abf8cac49dda1c53cf7aa2a428eefa49c42c4d8e 100644
--- a/src/util/mmap_cache.h
+++ b/src/util/mmap_cache.h
@@ -67,6 +67,9 @@ typedef uint32_t rel_ptr_t;
#define MC_SLOT_TO_PTR(base, slot, type) \
(type *)((base) + ((slot) * MC_SLOT_SIZE))
+#define MC_SLOT_WITHIN_BOUNDS(slot, dt_size) \
+ ((slot) < ((dt_size) / MC_SLOT_SIZE))
+
#define MC_VALID_BARRIER(val) (((val) & 0xff000000) == 0xf0000000)
#define MC_CHECK_RECORD_LENGTH(mc_ctx, rec) \
--
1.8.3.1