mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-21 08:19:28 +00:00
btrfs: convert extent_state.refs from atomic_t to refcount_t
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
parent
0700cea7c8
commit
b7ac31b7b2
2 changed files with 9 additions and 8 deletions
|
@ -68,7 +68,7 @@ void btrfs_leak_debug_check(void)
|
|||
pr_err("BTRFS: state leak: start %llu end %llu state %u in tree %d refs %d\n",
|
||||
state->start, state->end, state->state,
|
||||
extent_state_in_tree(state),
|
||||
atomic_read(&state->refs));
|
||||
refcount_read(&state->refs));
|
||||
list_del(&state->leak_list);
|
||||
kmem_cache_free(extent_state_cache, state);
|
||||
}
|
||||
|
@ -238,7 +238,7 @@ static struct extent_state *alloc_extent_state(gfp_t mask)
|
|||
state->failrec = NULL;
|
||||
RB_CLEAR_NODE(&state->rb_node);
|
||||
btrfs_leak_debug_add(&state->leak_list, &states);
|
||||
atomic_set(&state->refs, 1);
|
||||
refcount_set(&state->refs, 1);
|
||||
init_waitqueue_head(&state->wq);
|
||||
trace_alloc_extent_state(state, mask, _RET_IP_);
|
||||
return state;
|
||||
|
@ -248,7 +248,7 @@ void free_extent_state(struct extent_state *state)
|
|||
{
|
||||
if (!state)
|
||||
return;
|
||||
if (atomic_dec_and_test(&state->refs)) {
|
||||
if (refcount_dec_and_test(&state->refs)) {
|
||||
WARN_ON(extent_state_in_tree(state));
|
||||
btrfs_leak_debug_del(&state->leak_list);
|
||||
trace_free_extent_state(state, _RET_IP_);
|
||||
|
@ -641,7 +641,7 @@ static int __clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
|
|||
if (cached && extent_state_in_tree(cached) &&
|
||||
cached->start <= start && cached->end > start) {
|
||||
if (clear)
|
||||
atomic_dec(&cached->refs);
|
||||
refcount_dec(&cached->refs);
|
||||
state = cached;
|
||||
goto hit_next;
|
||||
}
|
||||
|
@ -793,7 +793,7 @@ static void wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
|
|||
|
||||
if (state->state & bits) {
|
||||
start = state->start;
|
||||
atomic_inc(&state->refs);
|
||||
refcount_inc(&state->refs);
|
||||
wait_on_state(tree, state);
|
||||
free_extent_state(state);
|
||||
goto again;
|
||||
|
@ -834,7 +834,7 @@ static void cache_state_if_flags(struct extent_state *state,
|
|||
if (cached_ptr && !(*cached_ptr)) {
|
||||
if (!flags || (state->state & flags)) {
|
||||
*cached_ptr = state;
|
||||
atomic_inc(&state->refs);
|
||||
refcount_inc(&state->refs);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
@ -1538,7 +1538,7 @@ static noinline u64 find_delalloc_range(struct extent_io_tree *tree,
|
|||
if (!found) {
|
||||
*start = state->start;
|
||||
*cached_state = state;
|
||||
atomic_inc(&state->refs);
|
||||
refcount_inc(&state->refs);
|
||||
}
|
||||
found++;
|
||||
*end = state->end;
|
||||
|
|
|
@ -2,6 +2,7 @@
|
|||
#define __EXTENTIO__
|
||||
|
||||
#include <linux/rbtree.h>
|
||||
#include <linux/refcount.h>
|
||||
#include "ulist.h"
|
||||
|
||||
/* bits for the extent state */
|
||||
|
@ -143,7 +144,7 @@ struct extent_state {
|
|||
|
||||
/* ADD NEW ELEMENTS AFTER THIS */
|
||||
wait_queue_head_t wq;
|
||||
atomic_t refs;
|
||||
refcount_t refs;
|
||||
unsigned state;
|
||||
|
||||
struct io_failure_record *failrec;
|
||||
|
|
Loading…
Reference in a new issue