In the Linux kernel, the following vulnerability has been resolved:
lib: alloc_tag_module_unload must wait for pending kfree_rcu calls
Ben Greear reports following splat:
------------[ cut here ]------------
net/netfilter/nf_nat_core.c:1114 module nf_nat func:nf_nat_register_fn has 256 allocated at module unload
WARNING: CPU: 1 PID: 10421 at lib/alloc_tag.c:168 alloc_tag_module_unload+0x22b/0x3f0
Modules linked in: nf_nat(-) btrfs ufs qnx4 hfsplus hfs minix vfat msdos fat
...
Hardware name: Default string Default string/SKYBAY, BIOS 5.12 08/04/2020
RIP: 0010:alloc_tag_module_unload+0x22b/0x3f0
codetag_unload_module+0x19b/0x2a0
? codetag_load_module+0x80/0x80
nf_nat module exit calls kfree_rcu on those addresses, but the free
operation is likely still pending by the time alloc_tag checks for leaks.
Wait for outstanding kfree_rcu operations to complete before checking
resolves this warning.
Reproducer:
unshare -n iptables-nft -t nat -A PREROUTING -p tcp
grep nf_nat /proc/allocinfo # will list 4 allocations
rmmod nft_chain_nat
rmmod nf_nat # will WARN.
[akpm@linux-foundation.org: add comment]
Metrics
Affected Vendors & Products
References
History
Thu, 13 Feb 2025 00:45:00 +0000
Type | Values Removed | Values Added |
---|---|---|
Weaknesses | CWE-667 |
Fri, 22 Nov 2024 14:00:00 +0000
Type | Values Removed | Values Added |
---|---|---|
References |
| |
Metrics |
threat_severity
|
cvssV3_1
|
Sat, 09 Nov 2024 10:30:00 +0000
Type | Values Removed | Values Added |
---|---|---|
Description | In the Linux kernel, the following vulnerability has been resolved: lib: alloc_tag_module_unload must wait for pending kfree_rcu calls Ben Greear reports following splat: ------------[ cut here ]------------ net/netfilter/nf_nat_core.c:1114 module nf_nat func:nf_nat_register_fn has 256 allocated at module unload WARNING: CPU: 1 PID: 10421 at lib/alloc_tag.c:168 alloc_tag_module_unload+0x22b/0x3f0 Modules linked in: nf_nat(-) btrfs ufs qnx4 hfsplus hfs minix vfat msdos fat ... Hardware name: Default string Default string/SKYBAY, BIOS 5.12 08/04/2020 RIP: 0010:alloc_tag_module_unload+0x22b/0x3f0 codetag_unload_module+0x19b/0x2a0 ? codetag_load_module+0x80/0x80 nf_nat module exit calls kfree_rcu on those addresses, but the free operation is likely still pending by the time alloc_tag checks for leaks. Wait for outstanding kfree_rcu operations to complete before checking resolves this warning. Reproducer: unshare -n iptables-nft -t nat -A PREROUTING -p tcp grep nf_nat /proc/allocinfo # will list 4 allocations rmmod nft_chain_nat rmmod nf_nat # will WARN. [akpm@linux-foundation.org: add comment] | |
Title | lib: alloc_tag_module_unload must wait for pending kfree_rcu calls | |
References |
|

Status: PUBLISHED
Assigner: Linux
Published: 2024-11-09T10:14:24.249Z
Updated: 2024-12-19T09:35:32.997Z
Reserved: 2024-10-21T19:36:19.971Z
Link: CVE-2024-50212

No data.

Status : Awaiting Analysis
Published: 2024-11-09T11:15:04.940
Modified: 2024-11-12T13:56:24.513
Link: CVE-2024-50212
