| Message ID | 20210528235250.2635167-3-memxor@gmail.com (mailing list archive) |
|---|---|
| State | RFC |
| Delegated to: | BPF |
| Headers | show |
| Series | Improve XDP samples usability and output | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for bpf-next |
| netdev/subject_prefix | success | Link |
| netdev/cc_maintainers | success | CCed 10 of 10 maintainers |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | warning | WARNING: Missing or malformed SPDX-License-Identifier tag in line 1 WARNING: use relative pathname instead of absolute in changelog text |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/header_inline | success | Link |
diff --git a/samples/bpf/cookie_uid_helper_example.c b/samples/bpf/cookie_uid_helper_example.c index cc3bce8d3aac..30fdcd664da2 100644 --- a/samples/bpf/cookie_uid_helper_example.c +++ b/samples/bpf/cookie_uid_helper_example.c @@ -1,3 +1,4 @@ + /* This test is a demo of using get_socket_uid and get_socket_cookie * helper function to do per socket based network traffic monitoring. * It requires iptables version higher then 1.6.1. to load pinned eBPF @@ -167,7 +168,7 @@ static void prog_load(void) static void prog_attach_iptables(char *file) { int ret; - char rules[100]; + char rules[256]; if (bpf_obj_pin(prog_fd, file)) error(1, errno, "bpf_obj_pin"); @@ -175,8 +176,13 @@ static void prog_attach_iptables(char *file) printf("file path too long: %s\n", file); exit(1); } - sprintf(rules, "iptables -A OUTPUT -m bpf --object-pinned %s -j ACCEPT", - file); + ret = snprintf(rules, sizeof(rules), + "iptables -A OUTPUT -m bpf --object-pinned %s -j ACCEPT", + file); + if (ret < 0 || ret >= sizeof(rules)) { + printf("error constructing iptables command\n"); + exit(1); + } ret = system(rules); if (ret < 0) { printf("iptables rule update failed: %d/n", WEXITSTATUS(ret)); diff --git a/samples/bpf/tracex4_user.c b/samples/bpf/tracex4_user.c index cea399424bca..566e6440e8c2 100644 --- a/samples/bpf/tracex4_user.c +++ b/samples/bpf/tracex4_user.c @@ -32,7 +32,7 @@ static void print_old_objects(int fd) __u64 key, next_key; struct pair v; - key = write(1, "\e[1;1H\e[2J", 12); /* clear screen */ + key = write(1, "\e[1;1H\e[2J", 11); /* clear screen */ key = -1; while (bpf_map_get_next_key(fd, &key, &next_key) == 0) {
cookie_uid_helper_example.c: In function ‘main’: cookie_uid_helper_example.c:178:69: warning: ‘ -j ACCEPT’ directive writing 10 bytes into a region of size between 8 and 58 [-Wformat-overflow=] 178 | sprintf(rules, "iptables -A OUTPUT -m bpf --object-pinned %s -j ACCEPT", | ^~~~~~~~~~ /home/kkd/src/linux/samples/bpf/cookie_uid_helper_example.c:178:9: note: ‘sprintf’ output between 53 and 103 bytes into a destination of size 100 178 | sprintf(rules, "iptables -A OUTPUT -m bpf --object-pinned %s -j ACCEPT", | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 179 | file); | ~~~~~ Fix by using snprintf and a sufficiently sized buffer. tracex4_user.c:35:15: warning: ‘write’ reading 12 bytes from a region of size 11 [-Wstringop-overread] 35 | key = write(1, "\e[1;1H\e[2J", 12); /* clear screen */ | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ Use size as 11. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> --- samples/bpf/cookie_uid_helper_example.c | 12 +++++++++--- samples/bpf/tracex4_user.c | 2 +- 2 files changed, 10 insertions(+), 4 deletions(-)