4.4-stable review patch. If anyone has any objections, please let me know.
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From: Bart Van Assche bart.vanassche@wdc.com
[ Upstream commit c02189e12ce3bf3808cb880569d3b10249f50bd9 ]
A left shift must shift less than the bit width of the left argument. Avoid triggering undefined behavior if ha->mbx_count == 32.
This patch avoids that UBSAN reports the following complaint:
UBSAN: Undefined behaviour in drivers/scsi/qla2xxx/qla_isr.c:275:14 shift exponent 32 is too large for 32-bit type 'int' Call Trace: dump_stack+0x4e/0x6c ubsan_epilogue+0xd/0x3b __ubsan_handle_shift_out_of_bounds+0x112/0x14c qla2x00_mbx_completion+0x1c5/0x25d [qla2xxx] qla2300_intr_handler+0x1ea/0x3bb [qla2xxx] qla2x00_mailbox_command+0x77b/0x139a [qla2xxx] qla2x00_mbx_reg_test+0x83/0x114 [qla2xxx] qla2x00_chip_diag+0x354/0x45f [qla2xxx] qla2x00_initialize_adapter+0x2c2/0xa4e [qla2xxx] qla2x00_probe_one+0x1681/0x392e [qla2xxx] pci_device_probe+0x10b/0x1f1 driver_probe_device+0x21f/0x3a4 __driver_attach+0xa9/0xe1 bus_for_each_dev+0x6e/0xb5 driver_attach+0x22/0x3c bus_add_driver+0x1d1/0x2ae driver_register+0x78/0x130 __pci_register_driver+0x75/0xa8 qla2x00_module_init+0x21b/0x267 [qla2xxx] do_one_initcall+0x5a/0x1e2 do_init_module+0x9d/0x285 load_module+0x20db/0x38e3 SYSC_finit_module+0xa8/0xbc SyS_finit_module+0x9/0xb do_syscall_64+0x77/0x271 entry_SYSCALL64_slow_path+0x25/0x25
Reported-by: Meelis Roos mroos@linux.ee Signed-off-by: Bart Van Assche bart.vanassche@wdc.com Cc: Himanshu Madhani himanshu.madhani@cavium.com Reviewed-by: Laurence Oberman loberman@redhat.com Acked-by: Himanshu Madhani himanshu.madhani@cavium.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 --- drivers/scsi/qla2xxx/qla_isr.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- a/drivers/scsi/qla2xxx/qla_isr.c +++ b/drivers/scsi/qla2xxx/qla_isr.c @@ -268,7 +268,8 @@ qla2x00_mbx_completion(scsi_qla_host_t * struct device_reg_2xxx __iomem *reg = &ha->iobase->isp;
/* Read all mbox registers? */ - mboxes = (1 << ha->mbx_count) - 1; + WARN_ON_ONCE(ha->mbx_count > 32); + mboxes = (1ULL << ha->mbx_count) - 1; if (!ha->mcp) ql_dbg(ql_dbg_async, vha, 0x5001, "MBX pointer ERROR.\n"); else @@ -2495,7 +2496,8 @@ qla24xx_mbx_completion(scsi_qla_host_t * struct device_reg_24xx __iomem *reg = &ha->iobase->isp24;
/* Read all mbox registers? */ - mboxes = (1 << ha->mbx_count) - 1; + WARN_ON_ONCE(ha->mbx_count > 32); + mboxes = (1ULL << ha->mbx_count) - 1; if (!ha->mcp) ql_dbg(ql_dbg_async, vha, 0x504e, "MBX pointer ERROR.\n"); else