CVE-2026-98058

01/Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Mark syscall helpers as sleepable bpf_sys_bpf() executes the bpf(2) syscall body, which can take mutexes, allocate with GFP_KERNEL, and wait for an RCU grace period. bpf_sys_close() reaches close_fd() and filp_close(), which can sleep as well. Both helpers are limited to BPF_PROG_TYPE_SYSCALL, whose main program is sleepable. That does not make every callback sleepable: a syscall program can register a bpf_timer callback, and the verifier checks that callback in a non-sleepable context while retaining the syscall helper set. Without .might_sleep on the prototypes, such a callback can invoke bpf_sys_bpf() from hrtimer softirq context and trigger a scheduling-while-atomic failure. bpf_sys_close() is exposed through the same missing context check. Set .might_sleep on both prototypes so the existing helper-context check rejects them from timer callbacks and other atomic regions. Calls from the sleepable main body remain valid.

02/Affected products

linux: linux kernel

03/References5

• git.kernel.org/stable/c/3408e98f06ce06ea6a58ca6c39da9c23f0029c06 Patch
• git.kernel.org/stable/c/65f636322ac402add6046c68e9ece77b9ffd71c9 Patch
• git.kernel.org/stable/c/9496d857205e60241034b798d7745ff8830ba599 Patch
• git.kernel.org/stable/c/d05524794240b52fdc3b6c1220dd05505715824d Patch
• git.kernel.org/stable/c/d8cfe9f71d302970ae393616960f2b3021d2b3b0 Patch