Re: [PATCH bpf v5 0/2] Fix bpf_probe_read_user_str() overcopying

2020-11-12 Thread Andrii Nakryiko
On Thu, Nov 12, 2020 at 11:13 AM Daniel Xu wrote: > > On Wed Nov 11, 2020 at 3:22 PM PST, Andrii Nakryiko wrote: > > On Wed, Nov 11, 2020 at 2:46 PM Daniel Xu wrote: > > > > > > 6ae08ae3dea2 ("bpf: Add probe_read_{user, kernel} and probe_read_{user, > > > kernel}_str helpers") introduced a subtle

Re: [PATCH bpf v5 0/2] Fix bpf_probe_read_user_str() overcopying

2020-11-12 Thread Daniel Xu
On Wed Nov 11, 2020 at 3:22 PM PST, Andrii Nakryiko wrote: > On Wed, Nov 11, 2020 at 2:46 PM Daniel Xu wrote: > > > > 6ae08ae3dea2 ("bpf: Add probe_read_{user, kernel} and probe_read_{user, > > kernel}_str helpers") introduced a subtle bug where > > bpf_probe_read_user_str() would potentially copy

[PATCH bpf v5 0/2] Fix bpf_probe_read_user_str() overcopying

2020-11-11 Thread Daniel Xu
6ae08ae3dea2 ("bpf: Add probe_read_{user, kernel} and probe_read_{user, kernel}_str helpers") introduced a subtle bug where bpf_probe_read_user_str() would potentially copy a few extra bytes after the NUL terminator. This issue is particularly nefarious when strings are used as map keys, as seemin

Re: [PATCH bpf v5 0/2] Fix bpf_probe_read_user_str() overcopying

2020-11-11 Thread Andrii Nakryiko
On Wed, Nov 11, 2020 at 2:46 PM Daniel Xu wrote: > > 6ae08ae3dea2 ("bpf: Add probe_read_{user, kernel} and probe_read_{user, > kernel}_str helpers") introduced a subtle bug where > bpf_probe_read_user_str() would potentially copy a few extra bytes after > the NUL terminator. > > This issue is part