Using the `exit` function for error handling entails
a number of problems:
- not a closed file;
- unreleased memory allocated for the certificate;
- non-deleted mapping to vmlinux file.
This patch fixes the listed issues.
Signed-off-by: Denis Glazkov <[email protected]>
---
Changes in version 2:
- refactored error handling, instead of fixing a single `read_file` function;
- changed the patch subject.
Version 1 was there:
- https://lore.kernel.org/all/[email protected]/
scripts/insert-sys-cert.c | 51 +++++++++++++++++++++++++--------------
1 file changed, 33 insertions(+), 18 deletions(-)
diff --git a/scripts/insert-sys-cert.c b/scripts/insert-sys-cert.c
index 8902836c2342..8046682188f3 100644
--- a/scripts/insert-sys-cert.c
+++ b/scripts/insert-sys-cert.c
@@ -101,7 +101,7 @@ static void get_symbol_from_map(Elf_Ehdr *hdr, FILE *f, char *name,
s->offset = 0;
if (fseek(f, 0, SEEK_SET) != 0) {
perror("File seek failed");
- exit(EXIT_FAILURE);
+ return;
}
while (fgets(l, LINE_SIZE, f)) {
p = strchr(l, '\n');
@@ -251,6 +251,7 @@ static char *read_file(char *file_name, int *size)
if (read(fd, buf, *size) != *size) {
perror("File read failed");
close(fd);
+ free(buf);
return NULL;
}
close(fd);
@@ -277,14 +278,15 @@ int main(int argc, char **argv)
char *cert_file = NULL;
int vmlinux_size;
int cert_size;
- Elf_Ehdr *hdr;
- char *cert;
- FILE *system_map;
+ Elf_Ehdr *hdr = NULL;
+ char *cert = NULL;
+ FILE *system_map = NULL;
unsigned long *lsize;
int *used;
int opt;
Elf_Shdr *symtab = NULL;
struct sym cert_sym, lsize_sym, used_sym;
+ int ret = EXIT_FAILURE;
while ((opt = getopt(argc, argv, "b:c:s:")) != -1) {
switch (opt) {
@@ -304,20 +306,20 @@ int main(int argc, char **argv)
if (!vmlinux_file || !cert_file) {
print_usage(argv[0]);
- exit(EXIT_FAILURE);
+ goto finish;
}
cert = read_file(cert_file, &cert_size);
if (!cert)
- exit(EXIT_FAILURE);
+ goto finish;
hdr = map_file(vmlinux_file, &vmlinux_size);
if (!hdr)
- exit(EXIT_FAILURE);
+ goto finish;
if (vmlinux_size < sizeof(*hdr)) {
err("Invalid ELF file.\n");
- exit(EXIT_FAILURE);
+ goto finish;
}
if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
@@ -325,22 +327,22 @@ int main(int argc, char **argv)
(hdr->e_ident[EI_MAG2] != ELFMAG2) ||
(hdr->e_ident[EI_MAG3] != ELFMAG3)) {
err("Invalid ELF magic.\n");
- exit(EXIT_FAILURE);
+ goto finish;
}
if (hdr->e_ident[EI_CLASS] != CURRENT_ELFCLASS) {
err("ELF class mismatch.\n");
- exit(EXIT_FAILURE);
+ goto finish;
}
if (hdr->e_ident[EI_DATA] != endianness()) {
err("ELF endian mismatch.\n");
- exit(EXIT_FAILURE);
+ goto finish;
}
if (hdr->e_shoff > vmlinux_size) {
err("Could not find section header.\n");
- exit(EXIT_FAILURE);
+ goto finish;
}
symtab = get_symbol_table(hdr);
@@ -349,13 +351,13 @@ int main(int argc, char **argv)
if (!system_map_file) {
err("Please provide a System.map file.\n");
print_usage(argv[0]);
- exit(EXIT_FAILURE);
+ goto finish;
}
system_map = fopen(system_map_file, "r");
if (!system_map) {
perror(system_map_file);
- exit(EXIT_FAILURE);
+ goto finish;
}
get_symbol_from_map(hdr, system_map, CERT_SYM, &cert_sym);
get_symbol_from_map(hdr, system_map, USED_SYM, &used_sym);
@@ -371,7 +373,7 @@ int main(int argc, char **argv)
}
if (!cert_sym.offset || !lsize_sym.offset || !used_sym.offset)
- exit(EXIT_FAILURE);
+ goto finish;
print_sym(hdr, &cert_sym);
print_sym(hdr, &used_sym);
@@ -382,14 +384,16 @@ int main(int argc, char **argv)
if (cert_sym.size < cert_size) {
err("Certificate is larger than the reserved area!\n");
- exit(EXIT_FAILURE);
+ goto finish;
}
+ ret = EXIT_SUCCESS;
+
/* If the existing cert is the same, don't overwrite */
if (cert_size == *used &&
strncmp(cert_sym.content, cert, cert_size) == 0) {
warn("Certificate was already inserted.\n");
- exit(EXIT_SUCCESS);
+ goto finish;
}
if (*used > 0)
@@ -406,5 +410,16 @@ int main(int argc, char **argv)
cert_sym.address);
info("Used %d bytes out of %d bytes reserved.\n", *used,
cert_sym.size);
- exit(EXIT_SUCCESS);
+
+finish:
+ if (cert != NULL)
+ free(cert);
+
+ if (hdr != NULL)
+ munmap(hdr, vmlinux_size);
+
+ if (system_map != NULL)
+ fclose(system_map);
+
+ return ret;
}
--
2.25.1