diff options
author | Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com> | 2017-11-17 19:14:55 -0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-02-03 17:04:29 +0100 |
commit | 03c2854d14bc4f55b145a9dc94ecdb03b9a231b3 (patch) | |
tree | a9eb29dd31ae4f0365010c71a96eb66698b7e1f0 /drivers/scsi | |
parent | dfd0feb42fc522a934e8b77fd8c2353f2c25f5af (diff) |
scsi: aacraid: Prevent crash in case of free interrupt during scsi EH path
[ Upstream commit e4717292ddebcfe231651b5aff9fa19ca158d178 ]
As part of the scsi EH path, aacraid performs a reinitialization of the
adapter, which encompass freeing resources and IRQs, NULLifying lots of
pointers, and then initialize it all over again. We've identified a
problem during the free IRQ portion of this path if CONFIG_DEBUG_SHIRQ
is enabled on kernel config file.
Happens that, in case this flag was set, right after free_irq()
effectively clears the interrupt, it checks if it was requested as
IRQF_SHARED. In positive case, it performs another call to the IRQ
handler on driver. Problem is: since aacraid currently free some
resources *before* freeing the IRQ, once free_irq() path calls the
handler again (due to CONFIG_DEBUG_SHIRQ), aacraid crashes due to NULL
pointer dereference with the following trace:
aac_src_intr_message+0xf8/0x740 [aacraid]
__free_irq+0x33c/0x4a0
free_irq+0x78/0xb0
aac_free_irq+0x13c/0x150 [aacraid]
aac_reset_adapter+0x2e8/0x970 [aacraid]
aac_eh_reset+0x3a8/0x5d0 [aacraid]
scsi_try_host_reset+0x74/0x180
scsi_eh_ready_devs+0xc70/0x1510
scsi_error_handler+0x624/0xa20
This patch prevents the crash by changing the order of the
deinitialization in this path of aacraid: first we clear the IRQ, then
we free other resources. No functional change intended.
Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Reviewed-by: Raghava Aditya Renukunta <RaghavaAditya.Renukunta@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/scsi')
-rw-r--r-- | drivers/scsi/aacraid/commsup.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/scsi/aacraid/commsup.c b/drivers/scsi/aacraid/commsup.c index 8c758c36fc70..766a9176b4ad 100644 --- a/drivers/scsi/aacraid/commsup.c +++ b/drivers/scsi/aacraid/commsup.c @@ -1363,13 +1363,13 @@ static int _aac_reset_adapter(struct aac_dev *aac, int forced) * will ensure that i/o is queisced and the card is flushed in that * case. */ + aac_free_irq(aac); aac_fib_map_free(aac); pci_free_consistent(aac->pdev, aac->comm_size, aac->comm_addr, aac->comm_phys); aac->comm_addr = NULL; aac->comm_phys = 0; kfree(aac->queues); aac->queues = NULL; - aac_free_irq(aac); kfree(aac->fsa_dev); aac->fsa_dev = NULL; quirks = aac_get_driver_ident(index)->quirks; |