scsi: target: core: Fix error path in target_setup_session()

BugLink: https://bugs.launchpad.net/bugs/2033931
commit 91271699228bfc66f1bc8abc0327169dc156d854 upstream.

In the error exits in target_setup_session(), if a branch is taken to
free_sess: transport_free_session() may call to target_free_cmd_counter()
and then fall through to call target_free_cmd_counter() a second time.
This can, and does, sometimes cause seg faults since the data field in
cmd_cnt->refcnt has been freed in the first call.

Fix this problem by simply returning after the call to
transport_free_session(). The second call is redundant for those cases.

Fixes: 4edba7e4a8f3 ("scsi: target: Move cmd counter allocation")
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Link: https://lore.kernel.org/r/20230613144259.12890-1-rpearsonhpe@gmail.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 86adff2a86eddb5baa9e436f58074be4d2478c30..687adc9e086ca942ba85dd591ab3b7bf76cc9192 100644 (file)
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -504,6 +504,8 @@ target_setup_session(struct se_portal_group *tpg,
 
 free_sess:
        transport_free_session(sess);
+       return ERR_PTR(rc);
+
 free_cnt:
        target_free_cmd_counter(cmd_cnt);
        return ERR_PTR(rc);