diff options
| author | Paulo Alcantara <pc@cjr.nz> | 2020-11-28 16:54:02 -0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-12-11 13:36:45 +0100 |
| commit | 87a3af64297a144ee9ab160cd55cfb90ef56305a (patch) | |
| tree | 2fea56a968edf41ee19adc6c7fd84f2cdafc6050 /fs/cifs/connect.c | |
| parent | 7b4a4b9403c52343d00901babc3987588bc0b085 (diff) | |
cifs: fix potential use-after-free in cifs_echo_request()
commit 212253367dc7b49ed3fc194ce71b0992eacaecf2 upstream.
This patch fixes a potential use-after-free bug in
cifs_echo_request().
For instance,
thread 1
--------
cifs_demultiplex_thread()
clean_demultiplex_info()
kfree(server)
thread 2 (workqueue)
--------
apic_timer_interrupt()
smp_apic_timer_interrupt()
irq_exit()
__do_softirq()
run_timer_softirq()
call_timer_fn()
cifs_echo_request() <- use-after-free in server ptr
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/cifs/connect.c')
| -rw-r--r-- | fs/cifs/connect.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index f4ef8d6ea8ed..71c9ed70aa68 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -783,6 +783,8 @@ static void clean_demultiplex_info(struct TCP_Server_Info *server) list_del_init(&server->tcp_ses_list); spin_unlock(&cifs_tcp_ses_lock); + cancel_delayed_work_sync(&server->echo); + spin_lock(&GlobalMid_Lock); server->tcpStatus = CifsExiting; spin_unlock(&GlobalMid_Lock); |