[PATCH 5.4 030/110] cifs: Fix memory allocation in __smb2_handle_cancelled_cmd()

Greg Kroah-Hartman
2020-01-30T18:52:45Z

From: Paulo Alcantara (SUSE) <pc@cjr.nz>

commit 0a5a98863c9debc02387b3d23c46d187756f5e2b upstream.

__smb2_handle_cancelled_cmd() is called under a spin lock held in
cifs_mid_q_entry_release(), so make its memory allocation GFP_ATOMIC.

This issue was observed when running xfstests generic/028:

[ 1722.589204] CIFS VFS: \\192.168.30.26 Cancelling wait for mid 72064 cmd: 5
[ 1722.590687] CIFS VFS: \\192.168.30.26 Cancelling wait for mid 72065 cmd: 17
[ 1722.593529] CIFS VFS: \\192.168.30.26 Cancelling wait for mid 72066 cmd: 6
[ 1723.039014] BUG: sleeping function called from invalid context at mm/slab.h:565
[ 1723.040710] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 30877, name: cifsd
[ 1723.045098] CPU: 3 PID: 30877 Comm: cifsd Not tainted 5.5.0-rc4+ #313
[ 1723.046256] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
[ 1723.048221] Call Trace:
[ 1723.048689] dump_stack+0x97/0xe0
[ 1723.049268] ___might_sleep.cold+0xd1/0xe1
[ 1723.050069] kmem_cache_alloc_trace+0x204/0x2b0
[ 1723.051051] __smb2_handle_cancelled_cmd+0x40/0x140 [cifs]
[ 1723.052137] smb2_handle_cancelled_mid+0xf6/0x120 [cifs]
[ 1723.053247] cifs_mid_q_entry_release+0x44d/0x630 [cifs]
[ 1723.054351] ? cifs_reconnect+0x26a/0x1620 [cifs]
[ 1723.055325] cifs_demultiplex_thread+0xad4/0x14a0 [cifs]
[ 1723.056458] ? cifs_handle_standard+0x2c0/0x2c0 [cifs]
[ 1723.057365] ? kvm_sched_clock_read+0x14/0x30
[ 1723.058197] ? sched_clock+0x5/0x10
[ 1723.058838] ? sched_clock_cpu+0x18/0x110
[ 1723.059629] ? lockdep_hardirqs_on+0x17d/0x250
[ 1723.060456] kthread+0x1ab/0x200
[ 1723.061149] ? cifs_handle_standard+0x2c0/0x2c0 [cifs]
[ 1723.062078] ? kthread_create_on_node+0xd0/0xd0
[ 1723.062897] ret_from_fork+0x3a/0x50

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Fixes: 9150c3adbf24 ("CIFS: Close open handle after interrupted close")
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/cifs/smb2misc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -750,7 +750,7 @@ __smb2_handle_cancelled_close(struct cif
{
struct close_cancelled_open *cancelled;

- cancelled = kzalloc(sizeof(*cancelled), GFP_KERNEL);
+ cancelled = kzalloc(sizeof(*cancelled), GFP_ATOMIC);
if (!cancelled)
return -ENOMEM;