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author | Lukasz Dorau <lukasz.dorau@intel.com> | 2013-04-03 10:27:17 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-04-16 21:48:28 -0700 |
commit | 978ddcd80a05229e14d8f078ee99bbf2d0f71867 (patch) | |
tree | d4d1d20f88071eba20f3e805aa15f44e9f11140d | |
parent | 16deae329e6b9a0a500d70c0cc4023c799b644d9 (diff) | |
download | lwn-978ddcd80a05229e14d8f078ee99bbf2d0f71867.tar.gz lwn-978ddcd80a05229e14d8f078ee99bbf2d0f71867.zip |
SCSI: libsas: fix handling vacant phy in sas_set_ex_phy()
commit d4a2618fa77b5e58ec15342972bd3505a1c3f551 upstream.
If a result of the SMP discover function is PHY VACANT,
the content of discover response structure (dr) is not valid.
It sometimes happens that dr->attached_sas_addr can contain
even SAS address of other phy. In such case an invalid phy
is created, what causes NULL pointer dereference during
destruction of expander's phys.
So if a result of SMP function is PHY VACANT, the content of discover
response structure (dr) must not be copied to phy structure.
This patch fixes the following bug:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
IP: [<ffffffff811c9002>] sysfs_find_dirent+0x12/0x90
Call Trace:
[<ffffffff811c95f5>] sysfs_get_dirent+0x35/0x80
[<ffffffff811cb55e>] sysfs_unmerge_group+0x1e/0xb0
[<ffffffff813329f4>] dpm_sysfs_remove+0x24/0x90
[<ffffffff8132b0f4>] device_del+0x44/0x1d0
[<ffffffffa016fc59>] sas_rphy_delete+0x9/0x20 [scsi_transport_sas]
[<ffffffffa01a16f6>] sas_destruct_devices+0xe6/0x110 [libsas]
[<ffffffff8107ac7c>] process_one_work+0x16c/0x350
[<ffffffff8107d84a>] worker_thread+0x17a/0x410
[<ffffffff81081b76>] kthread+0x96/0xa0
[<ffffffff81464944>] kernel_thread_helper+0x4/0x10
Signed-off-by: Lukasz Dorau <lukasz.dorau@intel.com>
Signed-off-by: Pawel Baldysiak <pawel.baldysiak@intel.com>
Reviewed-by: Maciej Patelczyk <maciej.patelczyk@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/scsi/libsas/sas_expander.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/scsi/libsas/sas_expander.c b/drivers/scsi/libsas/sas_expander.c index aec2e0da5016..1924d8b61b09 100644 --- a/drivers/scsi/libsas/sas_expander.c +++ b/drivers/scsi/libsas/sas_expander.c @@ -235,6 +235,17 @@ static void sas_set_ex_phy(struct domain_device *dev, int phy_id, void *rsp) linkrate = phy->linkrate; memcpy(sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE); + /* Handle vacant phy - rest of dr data is not valid so skip it */ + if (phy->phy_state == PHY_VACANT) { + memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE); + phy->attached_dev_type = NO_DEVICE; + if (!test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)) { + phy->phy_id = phy_id; + goto skip; + } else + goto out; + } + phy->attached_dev_type = to_dev_type(dr); if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)) goto out; @@ -272,6 +283,7 @@ static void sas_set_ex_phy(struct domain_device *dev, int phy_id, void *rsp) phy->phy->maximum_linkrate = dr->pmax_linkrate; phy->phy->negotiated_linkrate = phy->linkrate; + skip: if (new_phy) if (sas_phy_add(phy->phy)) { sas_phy_free(phy->phy); |