Null Pointer Dereference in sd_zbc_release_disk
From: Dongliang Mu
Date: Fri May 27 2022 - 01:52:16 EST
Hi maintainers,
I found a NPD(Null Pointer Dereference) in sd_zbc_release_disk function.
There are two definitions of sd_zbc_release_disk:
#ifdef CONFIG_BLK_DEV_ZONED
void sd_zbc_release_disk(struct scsi_disk *sdkp);
#else /* CONFIG_BLK_DEV_ZONED */
static inline void sd_zbc_release_disk(struct scsi_disk *sdkp) {}
#endif
When CONFIG_BLK_DEV_ZONED=y, the function implementation is as follows:
void sd_zbc_release_disk(struct scsi_disk *sdkp)
{
if (sd_is_zoned(sdkp))
sd_zbc_clear_zone_info(sdkp);
}
static inline int sd_is_zoned(struct scsi_disk *sdkp)
{
return sdkp->zoned == 1 || sdkp->device->type == TYPE_ZBC;
}
In drivers/scsi/sd.c, sd_probe() allocates sdkp with kzalloc(). If
errors occurred before the assignment "sdkp->device", after the
allocation, it will triggers a NPD in sd_is_zoned.
I am not familiar with kernel configuration. Does anyone have a
suggestion to fix this NPD?
I really appreciate any help you can provide.
--
My best regards to you.
No System Is Safe!
Dongliang Mu