CVE-2021-47218 (GCVE-0-2021-47218)
Vulnerability from cvelistv5 – Published: 2024-04-10 19:01 – Updated: 2025-05-04 07:06
VLAI?
Title
selinux: fix NULL-pointer dereference when hashtab allocation fails
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.
Severity ?
No CVSS data available.
Assigner
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Linux | Linux |
Affected:
03414a49ad5f3c56988c36d2070e402ffa17feaf , < b17dd53cac769dd13031b0ca34f90cc65e523fab
(git)
Affected: 03414a49ad5f3c56988c36d2070e402ffa17feaf , < 83c8ab8503adf56bf68dafc7a382f4946c87da79 (git) Affected: 03414a49ad5f3c56988c36d2070e402ffa17feaf , < dc27f3c5d10c58069672215787a96b4fae01818b (git) |
||
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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