This is a note to let you know that I've just added the patch titled
scsi: qla2xxx: Fix an integer overflow in sysfs code
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
scsi-qla2xxx-fix-an-integer-overflow-in-sysfs-code.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From e6f77540c067b48dee10f1e33678415bfcc89017 Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Date: Wed, 30 Aug 2017 16:30:35 +0300
Subject: scsi: qla2xxx: Fix an integer overflow in sysfs code
From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
commit e6f77540c067b48dee10f1e33678415bfcc89017 upstream.
The value of "size" comes from the user. When we add "start + size" it
could lead to an integer overflow bug.
It means we vmalloc() a lot more memory than we had intended. I believe
that on 64 bit systems vmalloc() can succeed even if we ask it to
allocate huge 4GB buffers. So we would get memory corruption and likely
a crash when we call ha->isp_ops->write_optrom() and ->read_optrom().
Only root can trigger this bug.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=194061
Fixes: b7cc176c9eb3 ("[SCSI] qla2xxx: Allow region-based flash-part accesses.")
Reported-by: shqking <shqking@xxxxxxxxx>
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/scsi/qla2xxx/qla_attr.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/scsi/qla2xxx/qla_attr.c
+++ b/drivers/scsi/qla2xxx/qla_attr.c
@@ -404,6 +404,8 @@ qla2x00_sysfs_write_optrom_ctl(struct fi
return -EINVAL;
if (start > ha->optrom_size)
return -EINVAL;
+ if (size > ha->optrom_size - start)
+ size = ha->optrom_size - start;
mutex_lock(&ha->optrom_mutex);
switch (val) {
@@ -429,8 +431,7 @@ qla2x00_sysfs_write_optrom_ctl(struct fi
}
ha->optrom_region_start = start;
- ha->optrom_region_size = start + size > ha->optrom_size ?
- ha->optrom_size - start : size;
+ ha->optrom_region_size = start + size;
ha->optrom_state = QLA_SREADING;
ha->optrom_buffer = vmalloc(ha->optrom_region_size);
@@ -503,8 +504,7 @@ qla2x00_sysfs_write_optrom_ctl(struct fi
}
ha->optrom_region_start = start;
- ha->optrom_region_size = start + size > ha->optrom_size ?
- ha->optrom_size - start : size;
+ ha->optrom_region_size = start + size;
ha->optrom_state = QLA_SWRITING;
ha->optrom_buffer = vmalloc(ha->optrom_region_size);
Patches currently in stable-queue which might be from dan.carpenter@xxxxxxxxxx are
queue-4.4/scsi-sg-off-by-one-in-sg_ioctl.patch
queue-4.4/scsi-qla2xxx-fix-an-integer-overflow-in-sysfs-code.patch