perf tools: Add O_CLOEXEC to open() calls in DSO and ELF code

open() calls in dso.c and symbol-elf.c omit O_CLOEXEC, which leaks
file descriptors to child processes spawned during symbol resolution
(e.g., addr2line, objdump).  This can exhaust the fd limit during
long profiling sessions or when processing many DSOs.

Add O_CLOEXEC to all open() calls in both files (12 call sites).

Fixes: cdd059d731eeb466 ("perf tools: Move dso_* related functions into dso object")
Fixes: e5a1845fc0aeca85 ("perf symbols: Split out util/symbol-elf.c")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
index 7dced896c64eafd763142e06d6d9cfd25bfcdea2..fb2e78fe2aa8eb9474b4ac89cf4c39e1644e12ff 100644 (file)
--- a/tools/perf/util/dso.c
+++ b/tools/perf/util/dso.c
@@ -344,7 +344,7 @@ int filename__decompress(const char *name, char *pathname,
         * descriptor to the uncompressed file.
         */
        if (!compressions[comp].is_compressed(name))
-               return open(name, O_RDONLY);
+               return open(name, O_RDONLY | O_CLOEXEC);
 
        fd = mkstemp(tmpbuf);
        if (fd < 0) {
@@ -1911,7 +1911,7 @@ static const u8 *__dso__read_symbol(struct dso *dso, const char *symfs_filename,
        int saved_errno;
 
        nsinfo__mountns_enter(dso__nsinfo(dso), &nsc);
-       fd = open(symfs_filename, O_RDONLY);
+       fd = open(symfs_filename, O_RDONLY | O_CLOEXEC);
        saved_errno = errno;
        nsinfo__mountns_exit(&nsc);
        if (fd < 0) {

diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
index 186e6d92ac3d774244bfadb9c14b33968957aa53..c2bdfd0003df2abe56acd3b5df1d5a91fa308eba 100644 (file)
--- a/tools/perf/util/symbol-elf.c
+++ b/tools/perf/util/symbol-elf.c
@@ -217,7 +217,7 @@ bool filename__has_section(const char *filename, const char *sec)
        GElf_Shdr shdr;
        bool found = false;
 
-       fd = open(filename, O_RDONLY);
+       fd = open(filename, O_RDONLY | O_CLOEXEC);
        if (fd < 0)
                return false;
 
@@ -872,7 +872,7 @@ static int read_build_id(const char *filename, struct build_id *bid)
        if (size < BUILD_ID_SIZE)
                goto out;
 
-       fd = open(filename, O_RDONLY);
+       fd = open(filename, O_RDONLY | O_CLOEXEC);
        if (fd < 0)
                goto out;
 
@@ -935,7 +935,7 @@ int sysfs__read_build_id(const char *filename, struct build_id *bid)
        size_t size = sizeof(bid->data);
        int fd, err = -1;
 
-       fd = open(filename, O_RDONLY);
+       fd = open(filename, O_RDONLY | O_CLOEXEC);
        if (fd < 0)
                goto out;
 
@@ -995,7 +995,7 @@ int filename__read_debuglink(const char *filename, char *debuglink,
        if (err >= 0)
                goto out;
 
-       fd = open(filename, O_RDONLY);
+       fd = open(filename, O_RDONLY | O_CLOEXEC);
        if (fd < 0)
                goto out;
 
@@ -1153,7 +1153,7 @@ int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name,
 
                type = dso__symtab_type(dso);
        } else {
-               fd = open(name, O_RDONLY);
+               fd = open(name, O_RDONLY | O_CLOEXEC);
                if (fd < 0) {
                        *dso__load_errno(dso) = errno;
                        return -1;
@@ -1952,7 +1952,7 @@ static int kcore__open(struct kcore *kcore, const char *filename)
 {
        GElf_Ehdr *ehdr;
 
-       kcore->fd = open(filename, O_RDONLY);
+       kcore->fd = open(filename, O_RDONLY | O_CLOEXEC);
        if (kcore->fd == -1)
                return -1;
 
@@ -1985,7 +1985,7 @@ static int kcore__init(struct kcore *kcore, char *filename, int elfclass,
        if (temp)
                kcore->fd = mkstemp(filename);
        else
-               kcore->fd = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0400);
+               kcore->fd = open(filename, O_WRONLY | O_CREAT | O_EXCL | O_CLOEXEC, 0400);
        if (kcore->fd == -1)
                return -1;
 
@@ -2461,11 +2461,11 @@ static int kcore_copy__compare_files(const char *from_filename,
 {
        int from, to, err = -1;
 
-       from = open(from_filename, O_RDONLY);
+       from = open(from_filename, O_RDONLY | O_CLOEXEC);
        if (from < 0)
                return -1;
 
-       to = open(to_filename, O_RDONLY);
+       to = open(to_filename, O_RDONLY | O_CLOEXEC);
        if (to < 0)
                goto out_close_from;
 
@@ -2883,7 +2883,7 @@ int get_sdt_note_list(struct list_head *head, const char *target)
        Elf *elf;
        int fd, ret;
 
-       fd = open(target, O_RDONLY);
+       fd = open(target, O_RDONLY | O_CLOEXEC);
        if (fd < 0)
                return -EBADF;