scsi: ufs: ufshcd-pltfrm: Fix memory leak due to probe defer

scsi: ufs: ufshcd-pltfrm: Fix memory leak due to probe defer

BugLink: https://bugs.launchpad.net/bugs/1951822
[ Upstream commit b6ca770ae7f2c560a29bbd02c4e3d734fafaf804 ]

UFS drivers that probe defer will end up leaking memory allocated for clk
and regulator names via kstrdup() because the structure that is holding
this memory is allocated via devm_* variants which will be freed during
probe defer but the names are never freed.

Use same devm_* variant of kstrdup to free the memory allocated to name
when driver probe defers.

Kmemleak found around 11 leaks on Qualcomm Dragon Board RB5:

unreferenced object 0xffff66f243fb2c00 (size 128):
  comm "kworker/u16:0", pid 7, jiffies 4294893319 (age 94.848s)
  hex dump (first 32 bytes):
    63 6f 72 65 5f 63 6c 6b 00 76 69 72 74 75 61 6c  core_clk.virtual
    2f 77 6f 72 6b 71 75 65 75 65 2f 73 63 73 69 5f  /workqueue/scsi_
  backtrace:
    [<000000006f788cd1>] slab_post_alloc_hook+0x88/0x410
    [<00000000cfd1372b>] __kmalloc_track_caller+0x138/0x230
    [<00000000a92ab17b>] kstrdup+0xb0/0x110
    [<0000000037263ab6>] ufshcd_pltfrm_init+0x1a8/0x500
    [<00000000a20a5caa>] ufs_qcom_probe+0x20/0x58
    [<00000000a5e43067>] platform_probe+0x6c/0x118
    [<00000000ef686e3f>] really_probe+0xc4/0x330
    [<000000005b18792c>] __driver_probe_device+0x88/0x118
    [<00000000a5d295e8>] driver_probe_device+0x44/0x158
    [<000000007e83f58d>] __device_attach_driver+0xb4/0x128
    [<000000004bfa4470>] bus_for_each_drv+0x68/0xd0
    [<00000000b89a83bc>] __device_attach+0xec/0x170
    [<00000000ada2beea>] device_initial_probe+0x14/0x20
    [<0000000079921612>] bus_probe_device+0x9c/0xa8
    [<00000000d268bf7c>] deferred_probe_work_func+0x90/0xd0
    [<000000009ef64bfa>] process_one_work+0x29c/0x788
unreferenced object 0xffff66f243fb2c80 (size 128):
  comm "kworker/u16:0", pid 7, jiffies 4294893319 (age 94.848s)
  hex dump (first 32 bytes):
    62 75 73 5f 61 67 67 72 5f 63 6c 6b 00 00 00 00  bus_aggr_clk....
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................

With this patch no memory leaks are reported.

Link: https://lore.kernel.org/r/20210914092214.6468-1-srinivas.kandagatla@linaro.org
Fixes: aa4976130934 ("ufs: Add regulator enable support")
Fixes: c6e79dacd86f ("ufs: Add clock initialization support")
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>