lkml.org 
[lkml]   [2019]   [Aug]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 5.2 121/162] scsi: ufs: Fix NULL pointer dereference in ufshcd_config_vreg_hpm()
    Date
    From: Adrian Hunter <adrian.hunter@intel.com>

    commit 7c7cfdcf7f1777c7376fc9a239980de04b6b5ea1 upstream.

    Fix the following BUG:

    [ 187.065689] BUG: kernel NULL pointer dereference, address: 000000000000001c
    [ 187.065790] RIP: 0010:ufshcd_vreg_set_hpm+0x3c/0x110 [ufshcd_core]
    [ 187.065938] Call Trace:
    [ 187.065959] ufshcd_resume+0x72/0x290 [ufshcd_core]
    [ 187.065980] ufshcd_system_resume+0x54/0x140 [ufshcd_core]
    [ 187.065993] ? pci_pm_restore+0xb0/0xb0
    [ 187.066005] ufshcd_pci_resume+0x15/0x20 [ufshcd_pci]
    [ 187.066017] pci_pm_thaw+0x4c/0x90
    [ 187.066030] dpm_run_callback+0x5b/0x150
    [ 187.066043] device_resume+0x11b/0x220

    Voltage regulators are optional, so functions must check they exist
    before dereferencing.

    Note this issue is hidden if CONFIG_REGULATORS is not set, because the
    offending code is optimised away.

    Notes for stable:

    The issue first appears in commit 57d104c153d3 ("ufs: add UFS power
    management support") but is inadvertently fixed in commit 60f0187031c0
    ("scsi: ufs: disable vccq if it's not needed by UFS device") which in
    turn was reverted by commit 730679817d83 ("Revert "scsi: ufs: disable vccq
    if it's not needed by UFS device""). So fix applies v3.18 to v4.5 and
    v5.1+

    Fixes: 57d104c153d3 ("ufs: add UFS power management support")
    Fixes: 730679817d83 ("Revert "scsi: ufs: disable vccq if it's not needed by UFS device"")
    Cc: stable@vger.kernel.org
    Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
    Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    drivers/scsi/ufs/ufshcd.c | 3 +++
    1 file changed, 3 insertions(+)

    --- a/drivers/scsi/ufs/ufshcd.c
    +++ b/drivers/scsi/ufs/ufshcd.c
    @@ -7032,6 +7032,9 @@ static inline int ufshcd_config_vreg_lpm
    static inline int ufshcd_config_vreg_hpm(struct ufs_hba *hba,
    struct ufs_vreg *vreg)
    {
    + if (!vreg)
    + return 0;
    +
    return ufshcd_config_vreg_load(hba->dev, vreg, vreg->max_uA);
    }


    \
     
     \ /
      Last update: 2019-08-27 10:05    [W:4.243 / U:0.164 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site