CVE-2021-47218 (GCVE-0-2021-47218)
Vulnerability from cvelistv5
Published
2024-04-10 19:01
Modified
2025-05-04 07:06
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: selinux: fix NULL-pointer dereference when hashtab allocation fails When the hash table slot array allocation fails in hashtab_init(), h->size is left initialized with a non-zero value, but the h->htable pointer is NULL. This may then cause a NULL pointer dereference, since the policydb code relies on the assumption that even after a failed hashtab_init(), hashtab_map() and hashtab_destroy() can be safely called on it. Yet, these detect an empty hashtab only by looking at the size. Fix this by making sure that hashtab_init() always leaves behind a valid empty hashtab when the allocation fails.
References
Impacted products
Vendor Product Version
Linux Linux Version: 03414a49ad5f3c56988c36d2070e402ffa17feaf
Version: 03414a49ad5f3c56988c36d2070e402ffa17feaf
Version: 03414a49ad5f3c56988c36d2070e402ffa17feaf
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