vidtv_channel_si_init() creates a temporary list (program, service, event)
and ownership of the memory itself is transferred to the PAT/SDT/EIT
tables through vidtv_psi_pat_program_assign(),
vidtv_psi_sdt_service_assign(), vidtv_psi_eit_event_assign().
The problem here is that the local pointer where the memory ownership
transfer was completed is not initialized to NULL. This causes the
vidtv_psi_pmt_create_sec_for_each_pat_entry() function to fail, and
in the flow that jumps to free_eit, the memory that was freed by
vidtv_psi_*_table_destroy() can be accessed again by
vidtv_psi_*_event_destroy() due to the uninitialized local pointer, so it
is freed once again.
Therefore, to prevent use-after-free and double-free vuln, local pointers
must be initialized to NULL when transferring memory ownership.
Cc: <stable(a)vger.kernel.org>
Reported-by: syzbot+1d9c0edea5907af239e0(a)syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=1d9c0edea5907af239e0
Fixes: 3be8037960bc ("media: vidtv: add error checks")
Signed-off-by: Jeongjun Park <aha310510(a)gmail.com>
---
v2: Improved patch description wording and CC stable mailing list
- Link to v1: https://lore.kernel.org/all/20250822065849.1145572-1-aha310510@gmail.com/
---
drivers/media/test-drivers/vidtv/vidtv_channel.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/media/test-drivers/vidtv/vidtv_channel.c b/drivers/media/test-drivers/vidtv/vidtv_channel.c
index f3023e91b3eb..3541155c6fc6 100644
--- a/drivers/media/test-drivers/vidtv/vidtv_channel.c
+++ b/drivers/media/test-drivers/vidtv/vidtv_channel.c
@@ -461,12 +461,15 @@ int vidtv_channel_si_init(struct vidtv_mux *m)
/* assemble all programs and assign to PAT */
vidtv_psi_pat_program_assign(m->si.pat, programs);
+ programs = NULL;
/* assemble all services and assign to SDT */
vidtv_psi_sdt_service_assign(m->si.sdt, services);
+ services = NULL;
/* assemble all events and assign to EIT */
vidtv_psi_eit_event_assign(m->si.eit, events);
+ events = NULL;
m->si.pmt_secs = vidtv_psi_pmt_create_sec_for_each_pat_entry(m->si.pat,
m->pcr_pid);
--
In the old days, RDS used FMR (Fast Memory Registration) to register
IB MRs to be used by RDMA. A newer and better verbs based
registration/de-registration method called FRWR (Fast Registration
Work Request) was added to RDS by commit 1659185fb4d0 ("RDS: IB:
Support Fastreg MR (FRMR) memory registration mode") in 2016.
Detection and enablement of FRWR was done in commit 2cb2912d6563
("RDS: IB: add Fastreg MR (FRMR) detection support"). But said commit
added an extern bool prefer_frmr, which was not used by said commit -
nor used by later commits. Hence, remove it.
Fixes: 2cb2912d6563 ("RDS: IB: add Fastreg MR (FRMR) detection support")
Cc: stable(a)vger.kernel.org
Signed-off-by: Håkon Bugge <haakon.bugge(a)oracle.com>
---
v1 -> v2:
* Added commit message
* Added Cc: stable(a)vger.kernel.org
---
net/rds/ib_mr.h | 1 -
1 file changed, 1 deletion(-)
diff --git a/net/rds/ib_mr.h b/net/rds/ib_mr.h
index ea5e9aee4959e..5884de8c6f45b 100644
--- a/net/rds/ib_mr.h
+++ b/net/rds/ib_mr.h
@@ -108,7 +108,6 @@ struct rds_ib_mr_pool {
};
extern struct workqueue_struct *rds_ib_mr_wq;
-extern bool prefer_frmr;
struct rds_ib_mr_pool *rds_ib_create_mr_pool(struct rds_ib_device *rds_dev,
int npages);
--
2.43.5