[v2] 53c700: add 'slot' check to NULL
Commit Message
Add a 'slot' check for a null value to avoid
dereferencing the null pointer
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Co-developed-by: Vladimir Telezhnikov <vtelezhnikov@astralinux.ru>
Signed-off-by: Vladimir Telezhnikov <vtelezhnikov@astralinux.ru>
Signed-off-by: Alexandra Diupina <adiupina@astralinux.ru>
---
v2: Move the 'slot' variable check to an existing if-else expression
as James E.J. Bottomley <James.Bottomley@HansenPartnership.com> suggested
drivers/scsi/53c700.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
Comments
On Fri, 28 Jul 2023 15:35:21 +0300, Alexandra Diupina wrote:
> Add a 'slot' check for a null value to avoid
> dereferencing the null pointer
>
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>
>
Applied to 6.5/scsi-fixes, thanks!
[1/1] 53c700: add 'slot' check to NULL
https://git.kernel.org/mkp/scsi/c/8366d1f1249a
@@ -1598,7 +1598,7 @@ NCR_700_intr(int irq, void *dev_id)
printk("scsi%d (%d:%d) PHASE MISMATCH IN SEND MESSAGE %d remain, return %p[%04x], phase %s\n", host->host_no, pun, lun, count, (void *)temp, temp - hostdata->pScript, sbcl_to_string(NCR_700_readb(host, SBCL_REG)));
#endif
resume_offset = hostdata->pScript + Ent_SendMessagePhaseMismatch;
- } else if(dsp >= to32bit(&slot->pSG[0].ins) &&
+ } else if (slot && dsp >= to32bit(&slot->pSG[0].ins) &&
dsp <= to32bit(&slot->pSG[NCR_700_SG_SEGMENTS].ins)) {
int data_transfer = NCR_700_readl(host, DBC_REG) & 0xffffff;
int SGcount = (dsp - to32bit(&slot->pSG[0].ins))/sizeof(struct NCR_700_SG_List);