| Message ID | 20221102084034.3342995-1-pulehui@huaweicloud.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 34de8e6e0e1f66e431abf4123934a2581cb5f133 |
| Delegated to: | BPF |
| Headers | show |
| Series | [bpf] bpftool: Fix NULL pointer dereference when pin {PROG, MAP, LINK} without FILE | expand |
2022-11-02 16:40 UTC+0800 ~ Pu Lehui <pulehui@huaweicloud.com> > From: Pu Lehui <pulehui@huawei.com> > > When using bpftool to pin {PROG, MAP, LINK} without FILE, > segmentation fault will occur. The reson is that the lack > of FILE will cause strlen to trigger NULL pointer dereference. > The corresponding stacktrace is shown below: > > do_pin > do_pin_any > do_pin_fd > mount_bpffs_for_pin > strlen(name) <- NULL pointer dereference > > Fix it by adding validation to the common process. > > Fixes: 75a1e792c335 ("tools: bpftool: Allow all prog/map handles for pinning objects") > Signed-off-by: Pu Lehui <pulehui@huawei.com> > --- > tools/bpf/bpftool/common.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c > index e4d33bc8bbbf..653c130a0aaa 100644 > --- a/tools/bpf/bpftool/common.c > +++ b/tools/bpf/bpftool/common.c > @@ -302,6 +302,9 @@ int do_pin_any(int argc, char **argv, int (*get_fd)(int *, char ***)) > int err; > int fd; > > + if (!REQ_ARGS(3)) > + return -EINVAL; > + > fd = get_fd(&argc, &argv); > if (fd < 0) > return fd; Good catch, and thanks for the fix! Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Hello: This patch was applied to bpf/bpf.git (master) by Daniel Borkmann <daniel@iogearbox.net>: On Wed, 2 Nov 2022 16:40:34 +0800 you wrote: > From: Pu Lehui <pulehui@huawei.com> > > When using bpftool to pin {PROG, MAP, LINK} without FILE, > segmentation fault will occur. The reson is that the lack > of FILE will cause strlen to trigger NULL pointer dereference. > The corresponding stacktrace is shown below: > > [...] Here is the summary with links: - [bpf] bpftool: Fix NULL pointer dereference when pin {PROG, MAP, LINK} without FILE https://git.kernel.org/bpf/bpf/c/34de8e6e0e1f You are awesome, thank you!
diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c index e4d33bc8bbbf..653c130a0aaa 100644 --- a/tools/bpf/bpftool/common.c +++ b/tools/bpf/bpftool/common.c @@ -302,6 +302,9 @@ int do_pin_any(int argc, char **argv, int (*get_fd)(int *, char ***)) int err; int fd; + if (!REQ_ARGS(3)) + return -EINVAL; + fd = get_fd(&argc, &argv); if (fd < 0) return fd;