From cb43285ff7039fe3c4b0bc476e6d6569c31104f3 Mon Sep 17 00:00:00 2001 From: Quinn Tran Date: Thu, 4 Feb 2016 11:45:16 -0500 Subject: qla2xxx: Fix stale pointer access. [ Upstream Commit 84e32a06f4f8756ce9ec3c8dc7e97896575f0771 ] Commit 84e32a0 ("qla2xxx: Use pci_enable_msix_range() instead of pci_enable_msix()") introduced a regression when target mode is enabled. In qla24xx_enable_msix(), ha->max_rsp_queues was incorrectly set to a value higher than the number of response queues allocated causing an invalid dereference. Specifically here in qla2x00_init_rings(): *rsp->in_ptr = 0; Add additional check to make sure the pointer is valid. following call stack will be seen ---- 8< ---- RIP: 0010:[] [] qla2x00_init_rings+0xdc/0x320 [qla2xxx] RSP: 0018:ffff880429447dd8 EFLAGS: 00010082 .... Call Trace: [] qla2x00_abort_isp+0x170/0x6b0 [qla2xxx] [] qla2x00_do_dpc+0x357/0x7f0 [qla2xxx] [] ? qla2x00_relogin+0x260/0x260 [qla2xxx] [] kthread+0xc9/0xe0 [] ? flush_kthread_worker+0x90/0x90 [] ret_from_fork+0x3f/0x70 [] ? flush_kthread_worker+0x90/0x90 ---- 8< ---- Cc: Signed-off-by: Quinn Tran Signed-off-by: Himanshu Madhani Signed-off-by: Nicholas Bellinger --- drivers/scsi/qla2xxx/qla_isr.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/scsi/qla2xxx/qla_isr.c') diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c index d4d65eb0e9b4..4af95479a9db 100644 --- a/drivers/scsi/qla2xxx/qla_isr.c +++ b/drivers/scsi/qla2xxx/qla_isr.c @@ -3063,9 +3063,9 @@ qla24xx_enable_msix(struct qla_hw_data *ha, struct rsp_que *rsp) "MSI-X: Failed to enable support " "-- %d/%d\n Retry with %d vectors.\n", ha->msix_count, ret, ret); + ha->msix_count = ret; + ha->max_rsp_queues = ha->msix_count - 1; } - ha->msix_count = ret; - ha->max_rsp_queues = ha->msix_count - 1; ha->msix_entries = kzalloc(sizeof(struct qla_msix_entry) * ha->msix_count, GFP_KERNEL); if (!ha->msix_entries) { -- cgit v1.2.3