blkdev_pr_read_keys() takes num_keys from userspace and uses it to
calculate the allocation size for keys_info via struct_size(). While
there is a check for SIZE_MAX (integer overflow), there is no upper
bound validation on the allocation size itself.
A malicious or buggy userspace can pass a large num_keys value that
doesn't trigger overflow but still results in an excessive allocation
attempt, causing a warning in the page allocator when the order exceeds
MAX_PAGE_ORDER.
Fix this by introducing PR_KEYS_MAX to limit the number of keys to
a sane value. This makes the SIZE_MAX check redundant, so remove it.
Also switch to kvzalloc/kvfree to handle larger allocations gracefully.
Fixes:
|
||
|---|---|---|
| .. | ||
| asm-generic | ||
| cxl | ||
| drm | ||
| fwctl | ||
| linux | ||
| misc | ||
| mtd | ||
| rdma | ||
| regulator | ||
| scsi | ||
| sound | ||
| video | ||
| xen | ||
| Kbuild | ||