Description
In the Linux kernel, the following vulnerability has been resolved: sched_ext: Fix scx_enable() crash on helper kthread creation failure A crash was observed when the sched_ext selftests runner was terminated with Ctrl+\ while test 15 was running: NIP [c00000000028fa58] scx_enable.constprop.0+0x358/0x12b0 LR [c00000000028fa2c] scx_enable.constprop.0+0x32c/0x12b0 Call Trace: scx_enable.constprop.0+0x32c/0x12b0 (unreliable) bpf_struct_ops_link_create+0x18c/0x22c __sys_bpf+0x23f8/0x3044 sys_bpf+0x2c/0x6c system_call_exception+0x124/0x320 system_call_vectored_common+0x15c/0x2ec kthread_run_worker() returns an ERR_PTR() on failure rather than NULL, but the current code in scx_alloc_and_add_sched() only checks for a NULL helper. Incase of failure on SIGQUIT, the error is not handled in scx_alloc_and_add_sched() and scx_enable() ends up dereferencing an error pointer. Error handling is fixed in scx_alloc_and_add_sched() to propagate PTR_ERR() into ret, so that scx_enable() jumps to the existing error path, avoiding random dereference on failure.
Product status
bff3b5aec1b727b620adc7c47085592802390125 (git) before 625e173e2a59b6cf6cbfb51c0a6bea47f3861eab
bff3b5aec1b727b620adc7c47085592802390125 (git) before 7b6216baae751369195fa3c83d434d23bcda406a
6.16
Any version before 6.16
6.17.10 (semver)
6.18 (original_commit_for_fix)
References
git.kernel.org/...c/625e173e2a59b6cf6cbfb51c0a6bea47f3861eab
git.kernel.org/...c/7b6216baae751369195fa3c83d434d23bcda406a
