Message ID | 20221216221855.4122288-1-kuifeng@meta.com (mailing list archive) |
---|---|
Headers | show |
Series | bpf: fix the crash caused by task iterators over vma | expand |
Hello: This series was applied to bpf/bpf.git (master) by Alexei Starovoitov <ast@kernel.org>: On Fri, 16 Dec 2022 14:18:53 -0800 you wrote: > This issue is related to task iterators over vma. A system crash can > occur when a task iterator travels through vma of tasks as the death > of a task will clear the pointer to its mm, even though the > task_struct is still held. As a result, an unexpected crash happens > due to a null pointer. To address this problem, a reference to mm is > kept on the iterator to make sure that the pointer is always > valid. This patch set provides a solution for this crash by properly > referencing mm on task iterators over vma. > > [...] Here is the summary with links: - [bpf-next,v2,1/2] bpf: keep a reference to the mm, in case the task is dead. https://git.kernel.org/bpf/bpf/c/7ff94f276f8e - [bpf-next,v2,2/2] selftests/bpf: add a test for iter/task_vma for short-lived processes https://git.kernel.org/bpf/bpf/c/b7793c8db7d9 You are awesome, thank you!
Hi everyone, This patchset seems to be forgot during the holiday season. Hope this message gets some notice. On Fri, 2022-12-16 at 14:18 -0800, Kui-Feng Lee wrote: > This issue is related to task iterators over vma. A system crash can > occur when a task iterator travels through vma of tasks as the death > of a task will clear the pointer to its mm, even though the > task_struct is still held. As a result, an unexpected crash happens > due to a null pointer. To address this problem, a reference to mm is > kept on the iterator to make sure that the pointer is always > valid. This patch set provides a solution for this crash by properly > referencing mm on task iterators over vma. > > The major changes from v1 are: > > - Fix commit logs of the test case. > > - Use reverse Christmas tree coding style. > > - Remove unnecessary error handling for time(). > > v1: > https://lore.kernel.org/bpf/20221216015912.991616-1-kuifeng@meta.com/ > > Kui-Feng Lee (2): > bpf: keep a reference to the mm, in case the task is dead. > selftests/bpf: add a test for iter/task_vma for short-lived > processes > > kernel/bpf/task_iter.c | 39 +++++++--- > .../selftests/bpf/prog_tests/bpf_iter.c | 73 > +++++++++++++++++++ > 2 files changed, 100 insertions(+), 12 deletions(-) >
On Wed, Jan 4, 2023 at 1:17 PM Kui-Feng Lee <kuifeng@meta.com> wrote: > > Hi everyone, > > This patchset seems to be forgot during the holiday season. > Hope this message gets some notice. It was applied to bpf tree commit 7ff94f276f8e ("bpf: keep a reference to the mm, in case the task is dead.")