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authorJeremy Allison <jra@samba.org>2009-10-05 10:27:48 -0700
committerJeremy Allison <jra@samba.org>2009-10-05 10:27:48 -0700
commit3fa1d7332c19d0521b8da9f2cd8162260f0ab660 (patch)
tree74f1fd62f1fe1f18ce8671a57bc5db15b56bce1e /source3/locking
parent76feeb1b97b1d8f24650c5198e9c61c4f5b1357a (diff)
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Fix bug 6776 - Running overlapping Byte Lock test will core dump Samba daemon.
Re-write core of POSIX locking logic. Jeremy.
Diffstat (limited to 'source3/locking')
-rw-r--r--source3/locking/brlock.c367
1 files changed, 219 insertions, 148 deletions
diff --git a/source3/locking/brlock.c b/source3/locking/brlock.c
index 05d6c7f95d..18a798182b 100644
--- a/source3/locking/brlock.c
+++ b/source3/locking/brlock.c
@@ -390,10 +390,9 @@ NTSTATUS brl_lock_windows_default(struct byte_range_lock *br_lck,
Cope with POSIX range splits and merges.
****************************************************************************/
-static unsigned int brlock_posix_split_merge(struct lock_struct *lck_arr, /* Output array. */
- const struct lock_struct *ex, /* existing lock. */
- const struct lock_struct *plock, /* proposed lock. */
- bool *lock_was_added)
+static unsigned int brlock_posix_split_merge(struct lock_struct *lck_arr, /* Output array. */
+ struct lock_struct *ex, /* existing lock. */
+ struct lock_struct *plock) /* proposed lock. */
{
bool lock_types_differ = (ex->lock_type != plock->lock_type);
@@ -410,21 +409,23 @@ static unsigned int brlock_posix_split_merge(struct lock_struct *lck_arr, /* Ou
/* Did we overlap ? */
/*********************************************
- +---------+
- | ex |
- +---------+
- +-------+
- | plock |
- +-------+
+ +---------+
+ | ex |
+ +---------+
+ +-------+
+ | plock |
+ +-------+
OR....
- +---------+
- | ex |
- +---------+
+ +---------+
+ | ex |
+ +---------+
**********************************************/
if ( (ex->start > (plock->start + plock->size)) ||
- (plock->start > (ex->start + ex->size))) {
+ (plock->start > (ex->start + ex->size))) {
+
/* No overlap with this lock - copy existing. */
+
memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
return 1;
}
@@ -436,26 +437,109 @@ OR....
+---------------------------+
| plock | -> replace with plock.
+---------------------------+
+OR
+ +---------------+
+ | ex |
+ +---------------+
+ +---------------------------+
+ | plock | -> replace with plock.
+ +---------------------------+
+
**********************************************/
if ( (ex->start >= plock->start) &&
- (ex->start + ex->size <= plock->start + plock->size) ) {
- memcpy(&lck_arr[0], plock, sizeof(struct lock_struct));
- *lock_was_added = True;
- return 1;
+ (ex->start + ex->size <= plock->start + plock->size) ) {
+
+ /* Replace - discard existing lock. */
+
+ return 0;
}
/*********************************************
+Adjacent after.
+ +-------+
+ | ex |
+ +-------+
+ +---------------+
+ | plock |
+ +---------------+
+
+BECOMES....
+ +---------------+-------+
+ | plock | ex | - different lock types.
+ +---------------+-------+
+OR.... (merge)
+ +-----------------------+
+ | plock | - same lock type.
+ +-----------------------+
+**********************************************/
+
+ if (plock->start + plock->size == ex->start) {
+
+ /* If the lock types are the same, we merge, if different, we
+ add the remainder of the old lock. */
+
+ if (lock_types_differ) {
+ /* Add existing. */
+ memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
+ return 1;
+ } else {
+ /* Merge - adjust incoming lock as we may have more
+ * merging to come. */
+ plock->size += ex->size;
+ return 0;
+ }
+ }
+
+/*********************************************
+Adjacent before.
+ +-------+
+ | ex |
+ +-------+
+ +---------------+
+ | plock |
+ +---------------+
+BECOMES....
+ +-------+---------------+
+ | ex | plock | - different lock types
+ +-------+---------------+
+
+OR.... (merge)
+ +-----------------------+
+ | plock | - same lock type.
+ +-----------------------+
+
+**********************************************/
+
+ if (ex->start + ex->size == plock->start) {
+
+ /* If the lock types are the same, we merge, if different, we
+ add the existing lock. */
+
+ if (lock_types_differ) {
+ memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
+ return 1;
+ } else {
+ /* Merge - adjust incoming lock as we may have more
+ * merging to come. */
+ plock->start = ex->start;
+ plock->size += ex->size;
+ return 0;
+ }
+ }
+
+/*********************************************
+Overlap after.
+-----------------------+
| ex |
+-----------------------+
+---------------+
| plock |
+---------------+
-OR....
- +-------+
- | ex |
- +-------+
+OR
+ +----------------+
+ | ex |
+ +----------------+
+---------------+
| plock |
+---------------+
@@ -466,60 +550,57 @@ BECOMES....
+---------------+-------+
OR.... (merge)
+-----------------------+
- | ex | - same lock type.
+ | plock | - same lock type.
+-----------------------+
**********************************************/
if ( (ex->start >= plock->start) &&
- (ex->start <= plock->start + plock->size) &&
- (ex->start + ex->size > plock->start + plock->size) ) {
-
- *lock_was_added = True;
+ (ex->start <= plock->start + plock->size) &&
+ (ex->start + ex->size > plock->start + plock->size) ) {
/* If the lock types are the same, we merge, if different, we
- add the new lock before the old. */
+ add the remainder of the old lock. */
if (lock_types_differ) {
- /* Add new. */
- memcpy(&lck_arr[0], plock, sizeof(struct lock_struct));
- memcpy(&lck_arr[1], ex, sizeof(struct lock_struct));
+ /* Add remaining existing. */
+ memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
/* Adjust existing start and size. */
- lck_arr[1].start = plock->start + plock->size;
- lck_arr[1].size = (ex->start + ex->size) - (plock->start + plock->size);
- return 2;
- } else {
- /* Merge. */
- memcpy(&lck_arr[0], plock, sizeof(struct lock_struct));
- /* Set new start and size. */
- lck_arr[0].start = plock->start;
- lck_arr[0].size = (ex->start + ex->size) - plock->start;
+ lck_arr[0].start = plock->start + plock->size;
+ lck_arr[0].size = (ex->start + ex->size) - (plock->start + plock->size);
return 1;
+ } else {
+ /* Merge - adjust incoming lock as we may have more
+ * merging to come. */
+ plock->size += (ex->start + ex->size) - (plock->start + plock->size);
+ return 0;
}
}
/*********************************************
- +-----------------------+
- | ex |
- +-----------------------+
- +---------------+
- | plock |
- +---------------+
-OR....
- +-------+
- | ex |
- +-------+
- +---------------+
- | plock |
- +---------------+
+Overlap before.
+ +-----------------------+
+ | ex |
+ +-----------------------+
+ +---------------+
+ | plock |
+ +---------------+
+OR
+ +-------------+
+ | ex |
+ +-------------+
+ +---------------+
+ | plock |
+ +---------------+
+
BECOMES....
- +-------+---------------+
- | ex | plock | - different lock types
- +-------+---------------+
+ +-------+---------------+
+ | ex | plock | - different lock types
+ +-------+---------------+
OR.... (merge)
- +-----------------------+
- | ex | - same lock type.
- +-----------------------+
+ +-----------------------+
+ | plock | - same lock type.
+ +-----------------------+
**********************************************/
@@ -527,27 +608,25 @@ OR.... (merge)
(ex->start + ex->size >= plock->start) &&
(ex->start + ex->size <= plock->start + plock->size) ) {
- *lock_was_added = True;
-
/* If the lock types are the same, we merge, if different, we
- add the new lock after the old. */
+ add the truncated old lock. */
if (lock_types_differ) {
memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
- memcpy(&lck_arr[1], plock, sizeof(struct lock_struct));
/* Adjust existing size. */
lck_arr[0].size = plock->start - ex->start;
- return 2;
- } else {
- /* Merge. */
- memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
- /* Adjust existing size. */
- lck_arr[0].size = (plock->start + plock->size) - ex->start;
return 1;
+ } else {
+ /* Merge - adjust incoming lock as we may have more
+ * merging to come. MUST ADJUST plock SIZE FIRST ! */
+ plock->size += (plock->start - ex->start);
+ plock->start = ex->start;
+ return 0;
}
}
/*********************************************
+Complete overlap.
+---------------------------+
| ex |
+---------------------------+
@@ -560,32 +639,31 @@ BECOMES.....
+-------+---------+---------+
OR
+---------------------------+
- | ex | - same lock type.
+ | plock | - same lock type.
+---------------------------+
**********************************************/
if ( (ex->start < plock->start) && (ex->start + ex->size > plock->start + plock->size) ) {
- *lock_was_added = True;
if (lock_types_differ) {
/* We have to split ex into two locks here. */
memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
- memcpy(&lck_arr[1], plock, sizeof(struct lock_struct));
- memcpy(&lck_arr[2], ex, sizeof(struct lock_struct));
+ memcpy(&lck_arr[1], ex, sizeof(struct lock_struct));
/* Adjust first existing size. */
lck_arr[0].size = plock->start - ex->start;
/* Adjust second existing start and size. */
- lck_arr[2].start = plock->start + plock->size;
- lck_arr[2].size = (ex->start + ex->size) - (plock->start + plock->size);
- return 3;
+ lck_arr[1].start = plock->start + plock->size;
+ lck_arr[1].size = (ex->start + ex->size) - (plock->start + plock->size);
+ return 2;
} else {
- /* Just eat plock. */
- memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
- return 1;
+ /* Just eat the existing locks, merge them into plock. */
+ plock->start = ex->start;
+ plock->size = ex->size;
+ return 0;
}
}
@@ -609,7 +687,6 @@ static NTSTATUS brl_lock_posix(struct messaging_context *msg_ctx,
unsigned int i, count, posix_count;
struct lock_struct *locks = br_lck->lock_data;
struct lock_struct *tp;
- bool lock_was_added = False;
bool signal_pending_read = False;
bool break_oplocks = false;
NTSTATUS status;
@@ -633,8 +710,9 @@ static NTSTATUS brl_lock_posix(struct messaging_context *msg_ctx,
if (!tp) {
return NT_STATUS_NO_MEMORY;
}
-
+
count = posix_count = 0;
+
for (i=0; i < br_lck->num_locks; i++) {
struct lock_struct *curr_lock = &locks[i];
@@ -671,7 +749,7 @@ static NTSTATUS brl_lock_posix(struct messaging_context *msg_ctx,
}
/* Work out overlaps. */
- tmp_count += brlock_posix_split_merge(&tp[count], curr_lock, plock, &lock_was_added);
+ tmp_count += brlock_posix_split_merge(&tp[count], curr_lock, plock);
posix_count += tmp_count;
count += tmp_count;
}
@@ -692,10 +770,21 @@ static NTSTATUS brl_lock_posix(struct messaging_context *msg_ctx,
LEVEL2_CONTEND_POSIX_BRL);
}
- if (!lock_was_added) {
- memcpy(&tp[count], plock, sizeof(struct lock_struct));
- count++;
+ /* Try and add the lock in order, sorted by lock start. */
+ for (i=0; i < count; i++) {
+ struct lock_struct *curr_lock = &tp[i];
+
+ if (curr_lock->start <= plock->start) {
+ continue;
+ }
+ }
+
+ if (i < count) {
+ memmove(&tp[i+1], &tp[i],
+ (count - i)*sizeof(struct lock_struct));
}
+ memcpy(&tp[i], plock, sizeof(struct lock_struct));
+ count++;
/* We can get the POSIX lock, now see if it needs to
be mapped into a lower level POSIX one, and if so can
@@ -729,12 +818,16 @@ static NTSTATUS brl_lock_posix(struct messaging_context *msg_ctx,
}
}
- /* Realloc so we don't leak entries per lock call. */
- tp = (struct lock_struct *)SMB_REALLOC(tp, count * sizeof(*locks));
- if (!tp) {
- status = NT_STATUS_NO_MEMORY;
- goto fail;
+ /* If we didn't use all the allocated size,
+ * Realloc so we don't leak entries per lock call. */
+ if (count < br_lck->num_locks + 2) {
+ tp = (struct lock_struct *)SMB_REALLOC(tp, count * sizeof(*locks));
+ if (!tp) {
+ status = NT_STATUS_NO_MEMORY;
+ goto fail;
+ }
}
+
br_lck->num_locks = count;
SAFE_FREE(br_lck->lock_data);
br_lck->lock_data = tp;
@@ -955,9 +1048,9 @@ bool brl_unlock_windows_default(struct messaging_context *msg_ctx,
static bool brl_unlock_posix(struct messaging_context *msg_ctx,
struct byte_range_lock *br_lck,
- const struct lock_struct *plock)
+ struct lock_struct *plock)
{
- unsigned int i, j, count, posix_count;
+ unsigned int i, j, count;
struct lock_struct *tp;
struct lock_struct *locks = br_lck->lock_data;
bool overlap_found = False;
@@ -984,11 +1077,9 @@ static bool brl_unlock_posix(struct messaging_context *msg_ctx,
return False;
}
- count = posix_count = 0;
+ count = 0;
for (i = 0; i < br_lck->num_locks; i++) {
struct lock_struct *lock = &locks[i];
- struct lock_struct tmp_lock[3];
- bool lock_was_added = False;
unsigned int tmp_count;
/* Only remove our own locks - ignore fnum. */
@@ -999,68 +1090,50 @@ static bool brl_unlock_posix(struct messaging_context *msg_ctx,
continue;
}
- /* Work out overlaps. */
- tmp_count = brlock_posix_split_merge(&tmp_lock[0], &locks[i], plock, &lock_was_added);
-
- if (tmp_count == 1) {
- /* Ether the locks didn't overlap, or the unlock completely
- overlapped this lock. If it didn't overlap, then there's
- no change in the locks. */
- if (tmp_lock[0].lock_type != UNLOCK_LOCK) {
- SMB_ASSERT(tmp_lock[0].lock_type == locks[i].lock_type);
- /* No change in this lock. */
- memcpy(&tp[count], &tmp_lock[0], sizeof(struct lock_struct));
- count++;
- posix_count++;
- } else {
- SMB_ASSERT(tmp_lock[0].lock_type == UNLOCK_LOCK);
- overlap_found = True;
- }
- continue;
- } else if (tmp_count == 2) {
- /* The unlock overlapped an existing lock. Copy the truncated
- lock into the lock array. */
- if (tmp_lock[0].lock_type != UNLOCK_LOCK) {
- SMB_ASSERT(tmp_lock[0].lock_type == locks[i].lock_type);
- SMB_ASSERT(tmp_lock[1].lock_type == UNLOCK_LOCK);
- memcpy(&tp[count], &tmp_lock[0], sizeof(struct lock_struct));
- if (tmp_lock[0].size != locks[i].size) {
- overlap_found = True;
- }
- } else {
- SMB_ASSERT(tmp_lock[0].lock_type == UNLOCK_LOCK);
- SMB_ASSERT(tmp_lock[1].lock_type == locks[i].lock_type);
- memcpy(&tp[count], &tmp_lock[1], sizeof(struct lock_struct));
- if (tmp_lock[1].start != locks[i].start) {
- overlap_found = True;
- }
+ if (lock->lock_flav == WINDOWS_LOCK) {
+ /* Do any Windows flavour locks conflict ? */
+ if (brl_conflict(lock, plock)) {
+ SAFE_FREE(tp);
+ return false;
}
+ /* Just copy the Windows lock into the new array. */
+ memcpy(&tp[count], lock, sizeof(struct lock_struct));
count++;
- posix_count++;
continue;
- } else {
- /* tmp_count == 3 - (we split a lock range in two). */
- SMB_ASSERT(tmp_lock[0].lock_type == locks[i].lock_type);
- SMB_ASSERT(tmp_lock[1].lock_type == UNLOCK_LOCK);
- SMB_ASSERT(tmp_lock[2].lock_type == locks[i].lock_type);
+ }
+
+ /* Work out overlaps. */
+ tmp_count = brlock_posix_split_merge(&tp[count], lock, plock);
+
+ if (tmp_count == 0) {
+ /* plock overlapped the existing lock completely,
+ or replaced it. Don't copy the existing lock. */
+ overlap_found = true;
+ } else if (tmp_count == 1) {
+ /* Either no overlap, (simple copy of existing lock) or
+ * an overlap of an existing lock. */
+ /* If the lock changed size, we had an overlap. */
+ if (tp[count].size != lock->size) {
+ overlap_found = true;
+ }
+ count += tmp_count;
+ } else if (tmp_count == 2) {
+ /* We split a lock range in two. */
+ overlap_found = true;
+ count += tmp_count;
- memcpy(&tp[count], &tmp_lock[0], sizeof(struct lock_struct));
- count++;
- posix_count++;
- memcpy(&tp[count], &tmp_lock[2], sizeof(struct lock_struct));
- count++;
- posix_count++;
- overlap_found = True;
/* Optimisation... */
/* We know we're finished here as we can't overlap any
more POSIX locks. Copy the rest of the lock array. */
+
if (i < br_lck->num_locks - 1) {
- memcpy(&tp[count], &locks[i+1],
+ memcpy(&tp[count], &locks[i+1],
sizeof(*locks)*((br_lck->num_locks-1) - i));
count += ((br_lck->num_locks-1) - i);
}
break;
}
+
}
if (!overlap_found) {
@@ -1093,10 +1166,8 @@ static bool brl_unlock_posix(struct messaging_context *msg_ctx,
tp = NULL;
}
- if (posix_count == 0) {
- contend_level2_oplocks_end(br_lck->fsp,
- LEVEL2_CONTEND_POSIX_BRL);
- }
+ contend_level2_oplocks_end(br_lck->fsp,
+ LEVEL2_CONTEND_POSIX_BRL);
br_lck->num_locks = count;
SAFE_FREE(br_lck->lock_data);