Fix a use-after-free bug for the userland stack.
Thanks to Mark Wodrich from Google for finding and reporting the
bug.
#if defined(__FreeBSD__) && !defined(__Userspace__)
#include <sys/cdefs.h>
-__FBSDID("$FreeBSD: head/sys/netinet/sctp_indata.c 363046 2020-07-09 16:18:42Z tuexen $");
+__FBSDID("$FreeBSD: head/sys/netinet/sctp_indata.c 363076 2020-07-10 11:15:10Z tuexen $");
#endif
#include <netinet/sctp_os.h>
@@ -1707,6 +1707,7 @@ sctp_process_a_data_chunk(struct sctp_tcb *stcb, struct sctp_association *asoc,
int *break_flag, int last_chunk, uint8_t chk_type)
{
struct sctp_tmit_chunk *chk = NULL; /* make gcc happy */
+ struct sctp_stream_in *strm;
uint32_t tsn, fsn, gap, mid;
struct mbuf *dmbuf;
int the_len;
@@ -2345,12 +2346,13 @@ finish_express_del:
/* All can be removed */
TAILQ_FOREACH_SAFE(control, &asoc->pending_reply_queue, next, ncontrol) {
TAILQ_REMOVE(&asoc->pending_reply_queue, control, next);
+ strm = &asoc->strmin[control->sinfo_stream];
sctp_queue_data_to_stream(stcb, asoc, control, abort_flag, &need_reasm_check);
if (*abort_flag) {
return (0);
}
if (need_reasm_check) {
- (void)sctp_deliver_reasm_check(stcb, asoc, &asoc->strmin[control->sinfo_stream], SCTP_READ_LOCK_NOT_HELD);
+ (void)sctp_deliver_reasm_check(stcb, asoc, strm, SCTP_READ_LOCK_NOT_HELD);
need_reasm_check = 0;
}
}
@@ -2365,12 +2367,13 @@ finish_express_del:
* control->sinfo_tsn > liste->tsn
*/
TAILQ_REMOVE(&asoc->pending_reply_queue, control, next);
+ strm = &asoc->strmin[control->sinfo_stream];
sctp_queue_data_to_stream(stcb, asoc, control, abort_flag, &need_reasm_check);
if (*abort_flag) {
return (0);
}
if (need_reasm_check) {
- (void)sctp_deliver_reasm_check(stcb, asoc, &asoc->strmin[control->sinfo_stream], SCTP_READ_LOCK_NOT_HELD);
+ (void)sctp_deliver_reasm_check(stcb, asoc, strm, SCTP_READ_LOCK_NOT_HELD);
need_reasm_check = 0;
}
}
