[U-Boot] [PATCH v1 4/4] env: fix memory leak in fw_env routines
Stefano Babic
sbabic at denx.de
Wed Apr 5 16:08:03 UTC 2017
fw_env_open allocates buffers to store the environment, but these
buffers are never freed. This becomes quite nasty using the fw_ tools as
library, because each access to the environment (even just reading a
variable) generates a memory leak equal to the size of the environment.
Fix this renaming fw_env_close() as fw_env_flush(), because the function
really flushes the environment from RAM to storage, and add a
fw_env_close function to free the allocated resources.
Signed-off-by: Stefano Babic <sbabic at denx.de>
---
tools/env/fw_env.c | 72 ++++++++++++++++++++++++++++++++++++++++++------------
tools/env/fw_env.h | 17 ++++++++++---
2 files changed, 70 insertions(+), 19 deletions(-)
diff --git a/tools/env/fw_env.c b/tools/env/fw_env.c
index fc3f4ce..299e0c9 100644
--- a/tools/env/fw_env.c
+++ b/tools/env/fw_env.c
@@ -278,6 +278,7 @@ int fw_printenv(int argc, char *argv[], int value_only, struct env_opts *opts)
printf ("%s\n", env);
}
+ fw_env_close(opts);
return 0;
}
@@ -300,10 +301,12 @@ int fw_printenv(int argc, char *argv[], int value_only, struct env_opts *opts)
printf("%s=%s\n", name, val);
}
+ fw_env_close(opts);
+
return rc;
}
-int fw_env_close(struct env_opts *opts)
+int fw_env_flush(struct env_opts *opts)
{
int ret;
@@ -472,6 +475,7 @@ int fw_setenv(int argc, char *argv[], struct env_opts *opts)
char *name, **valv;
char *value = NULL;
int valc;
+ int ret;
if (!opts)
opts = &default_opts;
@@ -491,8 +495,10 @@ int fw_setenv(int argc, char *argv[], struct env_opts *opts)
valv = argv + 1;
valc = argc - 1;
- if (env_flags_validate_env_set_params(name, valv, valc) < 0)
+ if (env_flags_validate_env_set_params(name, valv, valc) < 0) {
+ fw_env_close(opts);
return -1;
+ }
len = 0;
for (i = 0; i < valc; ++i) {
@@ -518,7 +524,10 @@ int fw_setenv(int argc, char *argv[], struct env_opts *opts)
free(value);
- return fw_env_close(opts);
+ ret = fw_env_flush(opts);
+ fw_env_close(opts);
+
+ return ret;
}
/*
@@ -639,7 +648,9 @@ int fw_parse_script(char *fname, struct env_opts *opts)
if (strcmp(fname, "-") != 0)
fclose(fp);
- ret |= fw_env_close(opts);
+ ret |= fw_env_flush(opts);
+
+ fw_env_close(opts);
return ret;
}
@@ -1105,11 +1116,11 @@ int fw_env_open(struct env_opts *opts)
{
int crc0, crc0_ok;
unsigned char flag0;
- void *addr0;
+ void *addr0 = NULL;
int crc1, crc1_ok;
unsigned char flag1;
- void *addr1;
+ void *addr1 = NULL;
int ret;
@@ -1120,14 +1131,15 @@ int fw_env_open(struct env_opts *opts)
opts = &default_opts;
if (parse_config(opts)) /* should fill envdevices */
- return -1;
+ return -EINVAL;
addr0 = calloc(1, CUR_ENVSIZE);
if (addr0 == NULL) {
fprintf(stderr,
"Not enough memory for environment (%ld bytes)\n",
CUR_ENVSIZE);
- return -1;
+ ret = -ENOMEM;
+ goto open_cleanup;
}
/* read environment from FLASH to local buffer */
@@ -1146,8 +1158,10 @@ int fw_env_open(struct env_opts *opts)
}
dev_current = 0;
- if (flash_io (O_RDONLY))
- return -1;
+ if (flash_io(O_RDONLY)) {
+ ret = -EIO;
+ goto open_cleanup;
+ }
crc0 = crc32 (0, (uint8_t *) environment.data, ENV_SIZE);
@@ -1155,7 +1169,7 @@ int fw_env_open(struct env_opts *opts)
ret = env_aes_cbc_crypt(environment.data, 0,
opts->aes_key);
if (ret)
- return ret;
+ goto open_cleanup;
}
crc0_ok = (crc0 == *environment.crc);
@@ -1174,7 +1188,8 @@ int fw_env_open(struct env_opts *opts)
fprintf(stderr,
"Not enough memory for environment (%ld bytes)\n",
CUR_ENVSIZE);
- return -1;
+ ret = -ENOMEM;
+ goto open_cleanup;
}
redundant = addr1;
@@ -1183,8 +1198,10 @@ int fw_env_open(struct env_opts *opts)
* other pointers in environment still point inside addr0
*/
environment.image = addr1;
- if (flash_io (O_RDONLY))
- return -1;
+ if (flash_io(O_RDONLY)) {
+ ret = -EIO;
+ goto open_cleanup;
+ }
/* Check flag scheme compatibility */
if (DEVTYPE(dev_current) == MTD_NORFLASH &&
@@ -1204,7 +1221,8 @@ int fw_env_open(struct env_opts *opts)
environment.flag_scheme = FLAG_INCREMENTAL;
} else {
fprintf (stderr, "Incompatible flash types!\n");
- return -1;
+ ret = -EINVAL;
+ goto open_cleanup;
}
crc1 = crc32 (0, (uint8_t *) redundant->data, ENV_SIZE);
@@ -1213,7 +1231,7 @@ int fw_env_open(struct env_opts *opts)
ret = env_aes_cbc_crypt(redundant->data, 0,
opts->aes_key);
if (ret)
- return ret;
+ goto open_cleanup;
}
crc1_ok = (crc1 == redundant->crc);
@@ -1285,6 +1303,28 @@ int fw_env_open(struct env_opts *opts)
#endif
}
return 0;
+
+open_cleanup:
+ if (addr0)
+ free(addr0);
+
+ if (addr1)
+ free(addr0);
+
+ return ret;
+}
+
+/*
+ * Simply free allocated buffer with environment
+ */
+int fw_env_close(struct env_opts *opts)
+{
+ if (environment.image)
+ free(environment.image);
+
+ environment.image = NULL;
+
+ return 0;
}
static int check_device_config(int dev)
diff --git a/tools/env/fw_env.h b/tools/env/fw_env.h
index cf346b3..04bb646 100644
--- a/tools/env/fw_env.h
+++ b/tools/env/fw_env.h
@@ -53,7 +53,7 @@ int fw_printenv(int argc, char *argv[], int value_only, struct env_opts *opts);
* @opts: how to retrieve environment from flash, defaults are used if NULL
*
* Description:
- * Uses fw_env_open, fw_env_write, fw_env_close
+ * Uses fw_env_open, fw_env_write, fw_env_flush
*
* Return:
* 0 on success, -1 on failure (modifies errno)
@@ -70,7 +70,7 @@ int fw_setenv(int argc, char *argv[], struct env_opts *opts);
* @opts: encryption key, configuration file, defaults are used if NULL
*
* Description:
- * Uses fw_env_open, fw_env_write, fw_env_close
+ * Uses fw_env_open, fw_env_write, fw_env_flush
*
* Return:
* 0 success, -1 on failure (modifies errno)
@@ -138,7 +138,17 @@ char *fw_getenv(char *name);
int fw_env_write(char *name, char *value);
/**
- * fw_env_close - write the environment from RAM cache back to flash
+ * fw_env_flush - write the environment from RAM cache back to flash
+ *
+ * @opts: encryption key, configuration file, defaults are used if NULL
+ *
+ * Return:
+ * 0 on success, -1 on failure (modifies errno)
+ */
+int fw_env_flush(struct env_opts *opts);
+
+/**
+ * fw_env_close - free allocated structure and close env
*
* @opts: encryption key, configuration file, defaults are used if NULL
*
@@ -147,6 +157,7 @@ int fw_env_write(char *name, char *value);
*/
int fw_env_close(struct env_opts *opts);
+
/**
* fw_env_version - return the current version of the library
*
--
2.7.4
More information about the U-Boot
mailing list