| Message ID | 20250414093402.384872-2-yangfeng59949@163.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | BPF |
| Headers | show |
| Series | libbpf: Fix event name too long error and add tests | expand |
On Mon, Apr 14, 2025 at 05:34:00PM +0800, Feng Yang wrote: > From: Feng Yang <yangfeng@kylinos.cn> > > When the binary path is excessively long, the generated probe_name in libbpf > exceeds the kernel's MAX_EVENT_NAME_LEN limit (64 bytes). > This causes legacy uprobe event attachment to fail with error code -22. > > Before Fix: > ./test_progs -t attach_probe/kprobe-long_name > ...... > libbpf: failed to add legacy kprobe event for 'bpf_kfunc_looooooooooooooooooooooooooooooong_name+0x0': -EINVAL > libbpf: prog 'handle_kprobe': failed to create kprobe 'bpf_kfunc_looooooooooooooooooooooooooooooong_name+0x0' perf event: -EINVAL > test_attach_kprobe_long_event_name:FAIL:attach_kprobe_long_event_name unexpected error: -22 > test_attach_probe:PASS:uprobe_ref_ctr_cleanup 0 nsec > #13/11 attach_probe/kprobe-long_name:FAIL > #13 attach_probe:FAIL > > ./test_progs -t attach_probe/uprobe-long_name > ...... > libbpf: failed to add legacy uprobe event for /root/linux-bpf/bpf-next/tools/testing/selftests/bpf/test_progs:0x13efd9: -EINVAL > libbpf: prog 'handle_uprobe': failed to create uprobe '/root/linux-bpf/bpf-next/tools/testing/selftests/bpf/test_progs:0x13efd9' perf event: -EINVAL > test_attach_uprobe_long_event_name:FAIL:attach_uprobe_long_event_name unexpected error: -22 > #13/10 attach_probe/uprobe-long_name:FAIL > #13 attach_probe:FAIL > After Fix: > ./test_progs -t attach_probe/uprobe-long_name > #13/10 attach_probe/uprobe-long_name:OK > #13 attach_probe:OK > Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED > > ./test_progs -t attach_probe/kprobe-long_name > #13/11 attach_probe/kprobe-long_name:OK > #13 attach_probe:OK > Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED > > Fixes: 46ed5fc33db9 ("libbpf: Refactor and simplify legacy kprobe code") > Fixes: cc10623c6810 ("libbpf: Add legacy uprobe attaching support") > Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com> > Signed-off-by: Feng Yang <yangfeng@kylinos.cn> > --- > tools/lib/bpf/libbpf.c | 19 ++++++++++++------- > 1 file changed, 12 insertions(+), 7 deletions(-) > > diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > index b2591f5cab65..9e047641e001 100644 > --- a/tools/lib/bpf/libbpf.c > +++ b/tools/lib/bpf/libbpf.c > @@ -60,6 +60,8 @@ > #define BPF_FS_MAGIC 0xcafe4a11 > #endif > > +#define MAX_EVENT_NAME_LEN 64 > + > #define BPF_FS_DEFAULT_PATH "/sys/fs/bpf" > > #define BPF_INSN_SZ (sizeof(struct bpf_insn)) > @@ -11142,10 +11144,10 @@ static void gen_kprobe_legacy_event_name(char *buf, size_t buf_sz, > static int index = 0; > int i; > > - snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx_%d", getpid(), kfunc_name, offset, > - __sync_fetch_and_add(&index, 1)); > + snprintf(buf, buf_sz, "libbpf_%u_%d_%s_0x%zx", getpid(), > + __sync_fetch_and_add(&index, 1), kfunc_name, offset); so the fix is to move unique id before kfunc_name to make sure it gets to the event name right? would be great to have it in changelog > > - /* sanitize binary_path in the probe name */ > + /* sanitize kfunc_name in the probe name */ > for (i = 0; buf[i]; i++) { > if (!isalnum(buf[i])) > buf[i] = '_'; > @@ -11270,7 +11272,7 @@ int probe_kern_syscall_wrapper(int token_fd) > > return pfd >= 0 ? 1 : 0; > } else { /* legacy mode */ > - char probe_name[128]; > + char probe_name[MAX_EVENT_NAME_LEN]; > > gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name), syscall_name, 0); > if (add_kprobe_event_legacy(probe_name, false, syscall_name, 0) < 0) > @@ -11328,7 +11330,7 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog, > func_name, offset, > -1 /* pid */, 0 /* ref_ctr_off */); > } else { > - char probe_name[256]; > + char probe_name[MAX_EVENT_NAME_LEN]; > > gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name), > func_name, offset); > @@ -11878,9 +11880,12 @@ static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, stru > static void gen_uprobe_legacy_event_name(char *buf, size_t buf_sz, > const char *binary_path, uint64_t offset) > { > + static int index = 0; > int i; > > - snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx", getpid(), binary_path, (size_t)offset); > + snprintf(buf, buf_sz, "libbpf_%u_%d_%s_0x%zx", getpid(), > + __sync_fetch_and_add(&index, 1), > + basename((void *)binary_path), (size_t)offset); gen_kprobe_legacy_event_name and gen_uprobe_legacy_event_name seem to be identical now, maybe we can have just one ? thanks, jirka > > /* sanitize binary_path in the probe name */ > for (i = 0; buf[i]; i++) { > @@ -12312,7 +12317,7 @@ bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid, > pfd = perf_event_open_probe(true /* uprobe */, retprobe, binary_path, > func_offset, pid, ref_ctr_off); > } else { > - char probe_name[PATH_MAX + 64]; > + char probe_name[MAX_EVENT_NAME_LEN]; > > if (ref_ctr_off) > return libbpf_err_ptr(-EINVAL); > -- > 2.43.0 >
On Mon, 14 Apr 2025 13:43:38 +0200 Jiri Olsa <olsajiri@gmail.com> wrote: > On Mon, Apr 14, 2025 at 05:34:00PM +0800, Feng Yang wrote: > > From: Feng Yang <yangfeng@kylinos.cn> > > > > When the binary path is excessively long, the generated probe_name in libbpf > > exceeds the kernel's MAX_EVENT_NAME_LEN limit (64 bytes). > > This causes legacy uprobe event attachment to fail with error code -22. > > > > Before Fix: > > ./test_progs -t attach_probe/kprobe-long_name > > ...... > > libbpf: failed to add legacy kprobe event for 'bpf_kfunc_looooooooooooooooooooooooooooooong_name+0x0': -EINVAL > > libbpf: prog 'handle_kprobe': failed to create kprobe 'bpf_kfunc_looooooooooooooooooooooooooooooong_name+0x0' perf event: -EINVAL > > test_attach_kprobe_long_event_name:FAIL:attach_kprobe_long_event_name unexpected error: -22 > > test_attach_probe:PASS:uprobe_ref_ctr_cleanup 0 nsec > > #13/11 attach_probe/kprobe-long_name:FAIL > > #13 attach_probe:FAIL > > > > ./test_progs -t attach_probe/uprobe-long_name > > ...... > > libbpf: failed to add legacy uprobe event for /root/linux-bpf/bpf-next/tools/testing/selftests/bpf/test_progs:0x13efd9: -EINVAL > > libbpf: prog 'handle_uprobe': failed to create uprobe '/root/linux-bpf/bpf-next/tools/testing/selftests/bpf/test_progs:0x13efd9' perf event: -EINVAL > > test_attach_uprobe_long_event_name:FAIL:attach_uprobe_long_event_name unexpected error: -22 > > #13/10 attach_probe/uprobe-long_name:FAIL > > #13 attach_probe:FAIL > > After Fix: > > ./test_progs -t attach_probe/uprobe-long_name > > #13/10 attach_probe/uprobe-long_name:OK > > #13 attach_probe:OK > > Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED > > > > ./test_progs -t attach_probe/kprobe-long_name > > #13/11 attach_probe/kprobe-long_name:OK > > #13 attach_probe:OK > > Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED > > > > Fixes: 46ed5fc33db9 ("libbpf: Refactor and simplify legacy kprobe code") > > Fixes: cc10623c6810 ("libbpf: Add legacy uprobe attaching support") > > Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com> > > Signed-off-by: Feng Yang <yangfeng@kylinos.cn> > > --- > > tools/lib/bpf/libbpf.c | 19 ++++++++++++------- > > 1 file changed, 12 insertions(+), 7 deletions(-) > > > > diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > > index b2591f5cab65..9e047641e001 100644 > > --- a/tools/lib/bpf/libbpf.c > > +++ b/tools/lib/bpf/libbpf.c > > @@ -60,6 +60,8 @@ > > #define BPF_FS_MAGIC 0xcafe4a11 > > #endif > > > > +#define MAX_EVENT_NAME_LEN 64 > > + > > #define BPF_FS_DEFAULT_PATH "/sys/fs/bpf" > > > > #define BPF_INSN_SZ (sizeof(struct bpf_insn)) > > @@ -11142,10 +11144,10 @@ static void gen_kprobe_legacy_event_name(char *buf, size_t buf_sz, > > static int index = 0; > > int i; > > > > - snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx_%d", getpid(), kfunc_name, offset, > > - __sync_fetch_and_add(&index, 1)); > > + snprintf(buf, buf_sz, "libbpf_%u_%d_%s_0x%zx", getpid(), > > + __sync_fetch_and_add(&index, 1), kfunc_name, offset); > > so the fix is to move unique id before kfunc_name to make sure it gets > to the event name right? would be great to have it in changelog > Yes, defining MAX_EVENT_NAME_LEN ensures event names are truncated via snprintf to prevent exceeding the maximum length limit. Moving the unique id before kfunc_name avoids truncating the id. Regarding the changelog: Should this information go into the commit message of the patch, or somewhere else? > > > > > - /* sanitize binary_path in the probe name */ > > + /* sanitize kfunc_name in the probe name */ > > for (i = 0; buf[i]; i++) { > > if (!isalnum(buf[i])) > > buf[i] = '_'; > > @@ -11270,7 +11272,7 @@ int probe_kern_syscall_wrapper(int token_fd) > > > > return pfd >= 0 ? 1 : 0; > > } else { /* legacy mode */ > > - char probe_name[128]; > > + char probe_name[MAX_EVENT_NAME_LEN]; > > > > gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name), syscall_name, 0); > > if (add_kprobe_event_legacy(probe_name, false, syscall_name, 0) < 0) > > @@ -11328,7 +11330,7 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog, > > func_name, offset, > > -1 /* pid */, 0 /* ref_ctr_off */); > > } else { > > - char probe_name[256]; > > + char probe_name[MAX_EVENT_NAME_LEN]; > > > > gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name), > > func_name, offset); > > @@ -11878,9 +11880,12 @@ static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, stru > > static void gen_uprobe_legacy_event_name(char *buf, size_t buf_sz, > > const char *binary_path, uint64_t offset) > > { > > + static int index = 0; > > int i; > > > > - snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx", getpid(), binary_path, (size_t)offset); > > + snprintf(buf, buf_sz, "libbpf_%u_%d_%s_0x%zx", getpid(), > > + __sync_fetch_and_add(&index, 1), > > + basename((void *)binary_path), (size_t)offset); > > gen_kprobe_legacy_event_name and gen_uprobe_legacy_event_name seem to > be identical now, maybe we can have just one ? > > thanks, > jirka > The gen_uprobe_legacy_event_name function includes an extra basename compared to gen_kprobe_legacy_event_name, as the prefixes of binary_path are often too similar to distinguish easily. When merging these two into a single function, is it acceptable to pass basename((void *)binary_path) directly during the uprobe invocation, or should we remove the addition of basename? Thank you! > > > > /* sanitize binary_path in the probe name */ > > for (i = 0; buf[i]; i++) { > > @@ -12312,7 +12317,7 @@ bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid, > > pfd = perf_event_open_probe(true /* uprobe */, retprobe, binary_path, > > func_offset, pid, ref_ctr_off); > > } else { > > - char probe_name[PATH_MAX + 64]; > > + char probe_name[MAX_EVENT_NAME_LEN]; > > > > if (ref_ctr_off) > > return libbpf_err_ptr(-EINVAL); > > -- > > 2.43.0 > >
On Tue, Apr 15, 2025 at 10:01:15AM +0800, Feng Yang wrote: > On Mon, 14 Apr 2025 13:43:38 +0200 Jiri Olsa <olsajiri@gmail.com> wrote: > > On Mon, Apr 14, 2025 at 05:34:00PM +0800, Feng Yang wrote: > > > From: Feng Yang <yangfeng@kylinos.cn> > > > > > > When the binary path is excessively long, the generated probe_name in libbpf > > > exceeds the kernel's MAX_EVENT_NAME_LEN limit (64 bytes). > > > This causes legacy uprobe event attachment to fail with error code -22. > > > > > > Before Fix: > > > ./test_progs -t attach_probe/kprobe-long_name > > > ...... > > > libbpf: failed to add legacy kprobe event for 'bpf_kfunc_looooooooooooooooooooooooooooooong_name+0x0': -EINVAL > > > libbpf: prog 'handle_kprobe': failed to create kprobe 'bpf_kfunc_looooooooooooooooooooooooooooooong_name+0x0' perf event: -EINVAL > > > test_attach_kprobe_long_event_name:FAIL:attach_kprobe_long_event_name unexpected error: -22 > > > test_attach_probe:PASS:uprobe_ref_ctr_cleanup 0 nsec > > > #13/11 attach_probe/kprobe-long_name:FAIL > > > #13 attach_probe:FAIL > > > > > > ./test_progs -t attach_probe/uprobe-long_name > > > ...... > > > libbpf: failed to add legacy uprobe event for /root/linux-bpf/bpf-next/tools/testing/selftests/bpf/test_progs:0x13efd9: -EINVAL > > > libbpf: prog 'handle_uprobe': failed to create uprobe '/root/linux-bpf/bpf-next/tools/testing/selftests/bpf/test_progs:0x13efd9' perf event: -EINVAL > > > test_attach_uprobe_long_event_name:FAIL:attach_uprobe_long_event_name unexpected error: -22 > > > #13/10 attach_probe/uprobe-long_name:FAIL > > > #13 attach_probe:FAIL > > > After Fix: > > > ./test_progs -t attach_probe/uprobe-long_name > > > #13/10 attach_probe/uprobe-long_name:OK > > > #13 attach_probe:OK > > > Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED > > > > > > ./test_progs -t attach_probe/kprobe-long_name > > > #13/11 attach_probe/kprobe-long_name:OK > > > #13 attach_probe:OK > > > Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED > > > > > > Fixes: 46ed5fc33db9 ("libbpf: Refactor and simplify legacy kprobe code") > > > Fixes: cc10623c6810 ("libbpf: Add legacy uprobe attaching support") > > > Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com> > > > Signed-off-by: Feng Yang <yangfeng@kylinos.cn> > > > --- > > > tools/lib/bpf/libbpf.c | 19 ++++++++++++------- > > > 1 file changed, 12 insertions(+), 7 deletions(-) > > > > > > diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > > > index b2591f5cab65..9e047641e001 100644 > > > --- a/tools/lib/bpf/libbpf.c > > > +++ b/tools/lib/bpf/libbpf.c > > > @@ -60,6 +60,8 @@ > > > #define BPF_FS_MAGIC 0xcafe4a11 > > > #endif > > > > > > +#define MAX_EVENT_NAME_LEN 64 > > > + > > > #define BPF_FS_DEFAULT_PATH "/sys/fs/bpf" > > > > > > #define BPF_INSN_SZ (sizeof(struct bpf_insn)) > > > @@ -11142,10 +11144,10 @@ static void gen_kprobe_legacy_event_name(char *buf, size_t buf_sz, > > > static int index = 0; > > > int i; > > > > > > - snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx_%d", getpid(), kfunc_name, offset, > > > - __sync_fetch_and_add(&index, 1)); > > > + snprintf(buf, buf_sz, "libbpf_%u_%d_%s_0x%zx", getpid(), > > > + __sync_fetch_and_add(&index, 1), kfunc_name, offset); > > > > so the fix is to move unique id before kfunc_name to make sure it gets > > to the event name right? would be great to have it in changelog > > > > Yes, defining MAX_EVENT_NAME_LEN ensures event names are truncated via snprintf > to prevent exceeding the maximum length limit. > Moving the unique id before kfunc_name avoids truncating the id. > Regarding the changelog: Should this information go into the commit message of the patch, or somewhere else? having this in changelog would help > > > > > > > > > - /* sanitize binary_path in the probe name */ > > > + /* sanitize kfunc_name in the probe name */ > > > for (i = 0; buf[i]; i++) { > > > if (!isalnum(buf[i])) > > > buf[i] = '_'; > > > @@ -11270,7 +11272,7 @@ int probe_kern_syscall_wrapper(int token_fd) > > > > > > return pfd >= 0 ? 1 : 0; > > > } else { /* legacy mode */ > > > - char probe_name[128]; > > > + char probe_name[MAX_EVENT_NAME_LEN]; > > > > > > gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name), syscall_name, 0); > > > if (add_kprobe_event_legacy(probe_name, false, syscall_name, 0) < 0) > > > @@ -11328,7 +11330,7 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog, > > > func_name, offset, > > > -1 /* pid */, 0 /* ref_ctr_off */); > > > } else { > > > - char probe_name[256]; > > > + char probe_name[MAX_EVENT_NAME_LEN]; > > > > > > gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name), > > > func_name, offset); > > > @@ -11878,9 +11880,12 @@ static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, stru > > > static void gen_uprobe_legacy_event_name(char *buf, size_t buf_sz, > > > const char *binary_path, uint64_t offset) > > > { > > > + static int index = 0; > > > int i; > > > > > > - snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx", getpid(), binary_path, (size_t)offset); > > > + snprintf(buf, buf_sz, "libbpf_%u_%d_%s_0x%zx", getpid(), > > > + __sync_fetch_and_add(&index, 1), > > > + basename((void *)binary_path), (size_t)offset); > > > > gen_kprobe_legacy_event_name and gen_uprobe_legacy_event_name seem to > > be identical now, maybe we can have just one ? > > > > thanks, > > jirka > > > > The gen_uprobe_legacy_event_name function includes an extra basename compared to gen_kprobe_legacy_event_name, > as the prefixes of binary_path are often too similar to distinguish easily. > When merging these two into a single function, is it acceptable to pass basename((void *)binary_path) > directly during the uprobe invocation, or should we remove the addition of basename? Thank you! I think basename is fine, perhaps just pass it as argument like below (on top of your change, untested) jirka --- diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 9e047641e001..93e804b25da1 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -11138,14 +11138,13 @@ static const char *tracefs_available_filter_functions_addrs(void) : TRACEFS"/available_filter_functions_addrs"; } -static void gen_kprobe_legacy_event_name(char *buf, size_t buf_sz, - const char *kfunc_name, size_t offset) +static void gen_legacy_event_name(char *buf, size_t buf_sz, const char *name, size_t offset) { static int index = 0; int i; snprintf(buf, buf_sz, "libbpf_%u_%d_%s_0x%zx", getpid(), - __sync_fetch_and_add(&index, 1), kfunc_name, offset); + __sync_fetch_and_add(&index, 1), name, offset); /* sanitize kfunc_name in the probe name */ for (i = 0; buf[i]; i++) { @@ -11274,7 +11273,7 @@ int probe_kern_syscall_wrapper(int token_fd) } else { /* legacy mode */ char probe_name[MAX_EVENT_NAME_LEN]; - gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name), syscall_name, 0); + gen_legacy_event_name(probe_name, sizeof(probe_name), syscall_name, 0); if (add_kprobe_event_legacy(probe_name, false, syscall_name, 0) < 0) return 0; @@ -11332,8 +11331,7 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog, } else { char probe_name[MAX_EVENT_NAME_LEN]; - gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name), - func_name, offset); + gen_legacy_event_name(probe_name, sizeof(probe_name), func_name, offset); legacy_probe = strdup(probe_name); if (!legacy_probe) @@ -11877,23 +11875,6 @@ static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, stru return ret; } -static void gen_uprobe_legacy_event_name(char *buf, size_t buf_sz, - const char *binary_path, uint64_t offset) -{ - static int index = 0; - int i; - - snprintf(buf, buf_sz, "libbpf_%u_%d_%s_0x%zx", getpid(), - __sync_fetch_and_add(&index, 1), - basename((void *)binary_path), (size_t)offset); - - /* sanitize binary_path in the probe name */ - for (i = 0; buf[i]; i++) { - if (!isalnum(buf[i])) - buf[i] = '_'; - } -} - static inline int add_uprobe_event_legacy(const char *probe_name, bool retprobe, const char *binary_path, size_t offset) { @@ -12322,8 +12303,8 @@ bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid, if (ref_ctr_off) return libbpf_err_ptr(-EINVAL); - gen_uprobe_legacy_event_name(probe_name, sizeof(probe_name), - binary_path, func_offset); + gen_legacy_event_name(probe_name, sizeof(probe_name), + basename((char *) binary_path), func_offset); legacy_probe = strdup(probe_name); if (!legacy_probe)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index b2591f5cab65..9e047641e001 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -60,6 +60,8 @@ #define BPF_FS_MAGIC 0xcafe4a11 #endif +#define MAX_EVENT_NAME_LEN 64 + #define BPF_FS_DEFAULT_PATH "/sys/fs/bpf" #define BPF_INSN_SZ (sizeof(struct bpf_insn)) @@ -11142,10 +11144,10 @@ static void gen_kprobe_legacy_event_name(char *buf, size_t buf_sz, static int index = 0; int i; - snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx_%d", getpid(), kfunc_name, offset, - __sync_fetch_and_add(&index, 1)); + snprintf(buf, buf_sz, "libbpf_%u_%d_%s_0x%zx", getpid(), + __sync_fetch_and_add(&index, 1), kfunc_name, offset); - /* sanitize binary_path in the probe name */ + /* sanitize kfunc_name in the probe name */ for (i = 0; buf[i]; i++) { if (!isalnum(buf[i])) buf[i] = '_'; @@ -11270,7 +11272,7 @@ int probe_kern_syscall_wrapper(int token_fd) return pfd >= 0 ? 1 : 0; } else { /* legacy mode */ - char probe_name[128]; + char probe_name[MAX_EVENT_NAME_LEN]; gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name), syscall_name, 0); if (add_kprobe_event_legacy(probe_name, false, syscall_name, 0) < 0) @@ -11328,7 +11330,7 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog, func_name, offset, -1 /* pid */, 0 /* ref_ctr_off */); } else { - char probe_name[256]; + char probe_name[MAX_EVENT_NAME_LEN]; gen_kprobe_legacy_event_name(probe_name, sizeof(probe_name), func_name, offset); @@ -11878,9 +11880,12 @@ static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, stru static void gen_uprobe_legacy_event_name(char *buf, size_t buf_sz, const char *binary_path, uint64_t offset) { + static int index = 0; int i; - snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx", getpid(), binary_path, (size_t)offset); + snprintf(buf, buf_sz, "libbpf_%u_%d_%s_0x%zx", getpid(), + __sync_fetch_and_add(&index, 1), + basename((void *)binary_path), (size_t)offset); /* sanitize binary_path in the probe name */ for (i = 0; buf[i]; i++) { @@ -12312,7 +12317,7 @@ bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid, pfd = perf_event_open_probe(true /* uprobe */, retprobe, binary_path, func_offset, pid, ref_ctr_off); } else { - char probe_name[PATH_MAX + 64]; + char probe_name[MAX_EVENT_NAME_LEN]; if (ref_ctr_off) return libbpf_err_ptr(-EINVAL);