4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Meelis Roos <mr...@linux.ee> [ Upstream commit 00c20cdc79259c6c5bf978b21af96c2d3edb646d ] When aacraid init fails with "AAC0: adapter self-test failed.", shutdown leads to UBSAN warning and then oops: [154316.118423] ================================================================================ [154316.118508] UBSAN: Undefined behaviour in drivers/scsi/scsi_lib.c:2328:27 [154316.118566] member access within null pointer of type 'struct Scsi_Host' [154316.118631] CPU: 2 PID: 14530 Comm: reboot Tainted: G W 4.15.0-dirty #89 [154316.118701] Hardware name: Hewlett Packard HP NetServer/HP System Board, BIOS 4.06.46 PW 06/25/2003 [154316.118774] Call Trace: [154316.118848] dump_stack+0x48/0x65 [154316.118916] ubsan_epilogue+0xe/0x40 [154316.118976] __ubsan_handle_type_mismatch+0xfb/0x180 [154316.119043] scsi_block_requests+0x20/0x30 [154316.119135] aac_shutdown+0x18/0x40 [aacraid] [154316.119196] pci_device_shutdown+0x33/0x50 [154316.119269] device_shutdown+0x18a/0x390 [...] [154316.123435] BUG: unable to handle kernel NULL pointer dereference at 000000f4 [154316.123515] IP: scsi_block_requests+0xa/0x30 This is because aac_shutdown() does struct Scsi_Host *shost = pci_get_drvdata(dev); scsi_block_requests(shost); and that assumes shost has been assigned with pci_set_drvdata(). However, pci_set_drvdata(pdev, shost) is done in aac_probe_one() far after bailing out with error from calling the init function ((*aac_drivers[index].init)(aac)), and when the init function fails, no error is returned from aac_probe_one() so PCI layer assumes there is driver attached, and tries to shut it down later. Fix it by returning error from aac_probe_one() when card-specific init function fails. This fixes reboot on my HP NetRAID-4M with dead battery. Signed-off-by: Meelis Roos <mr...@linux.ee> Reviewed-by: Dave Carroll <david.carr...@microsemi.com> Signed-off-by: Martin K. Petersen <martin.peter...@oracle.com> Signed-off-by: Sasha Levin <alexander.le...@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- drivers/scsi/aacraid/linit.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/scsi/aacraid/linit.c +++ b/drivers/scsi/aacraid/linit.c @@ -1203,8 +1203,10 @@ static int aac_probe_one(struct pci_dev * Map in the registers from the adapter. */ aac->base_size = AAC_MIN_FOOTPRINT_SIZE; - if ((*aac_drivers[index].init)(aac)) + if ((*aac_drivers[index].init)(aac)) { + error = -ENODEV; goto out_unmap; + } if (aac->sync_mode) { if (aac_sync_mode)