From: Viacheslav Dubeyko <Slava.Dubeyko@xxxxxxx>
smatch warnings:
fs/ceph/super.c:1042 ceph_umount_begin() warn: variable dereferenced before check 'fsc' (see line 1041)
vim +/fsc +1042 fs/ceph/super.c
void ceph_umount_begin(struct super_block *sb)
{
struct ceph_fs_client *fsc = ceph_sb_to_fs_client(sb);
doutc(fsc->client, "starting forced umount\n");
^^^^^^^^^^^
Dereferenced
if (!fsc)
^^^^
Checked too late.
return;
fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
__ceph_umount_begin(fsc);
}
The VFS guarantees that the superblock is still
alive when it calls into ceph via ->umount_begin().
Finally, we don't need to check the fsc and
it should be valid. This patch simply removes
the fsc check.
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Closes: https://urldefense.proofpoint.com/v2/url?u=https-3A__lore.kernel.org_r_202503280852.YDB3pxUY-2Dlkp-40intel.com_&d=DwIBAg&c=BSDicqBQBDjDI9RkVyTcHQ&r=q5bIm4AXMzc8NJu1_RGmnQ2fMWKq4Y4RAkElvUgSs00&m=Ud7uNdqBY_Z7LJ_oI4fwdhvxOYt_5Q58tpkMQgDWhV3199_TCnINFU28Esc0BaAH&s=QOKWZ9HKLyd6XCxW-AUoKiFFg9roId6LOM01202zAk0&e=
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@xxxxxxx>
---
fs/ceph/super.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index f3951253e393..68a6d434093f 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -1033,8 +1033,7 @@ void ceph_umount_begin(struct super_block *sb)
struct ceph_fs_client *fsc = ceph_sb_to_fs_client(sb);
doutc(fsc->client, "starting forced umount\n");
- if (!fsc)
- return;
+
fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
__ceph_umount_begin(fsc);
}
--
2.49.0
