From: Eric Biggers <ebiggers@xxxxxxxxxx>
Fix two -Wstringop-truncation warnings in is_ext4() by simplifying how
how mnt_type is handled and by using the correct bound for mnt_fsname.
Fix a -Wstringop-truncation warning in main() by replacing the fragile
pattern 'strncpy(dst, src, strnlen(src, N))', which doesn't
null-terminate the destination string, with a standard string copy. (It
happened to work anyway because dst happens to be zero-initialized.)
These warnings showed up when building with -Wall with gcc 8 or later.
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
---
misc/e4defrag.c | 30 +++++++++---------------------
1 file changed, 9 insertions(+), 21 deletions(-)
diff --git a/misc/e4defrag.c b/misc/e4defrag.c
index 9ec265f2e..33bd05d2c 100644
--- a/misc/e4defrag.c
+++ b/misc/e4defrag.c
@@ -258,12 +258,12 @@ static int get_mount_point(const char *devname, char *mount_point,
*
* @file: the file's name.
*/
-static int is_ext4(const char *file, char *devname)
+static int is_ext4(const char *file, char devname[PATH_MAX + 1])
{
int maxlen = 0;
int len, ret;
+ int type_is_ext4 = 0;
FILE *fp = NULL;
- char *mnt_type = NULL;
/* Refer to /etc/mtab */
const char *mtab = MOUNTED;
char file_path[PATH_MAX + 1];
@@ -307,26 +307,16 @@ static int is_ext4(const char *file, char *devname)
maxlen = len;
- mnt_type = realloc(mnt_type, strlen(mnt->mnt_type) + 1);
- if (mnt_type == NULL) {
- endmntent(fp);
- return -1;
- }
- memset(mnt_type, 0, strlen(mnt->mnt_type) + 1);
- strncpy(mnt_type, mnt->mnt_type, strlen(mnt->mnt_type));
+ type_is_ext4 = !strcmp(mnt->mnt_type, FS_EXT4);
strncpy(lost_found_dir, mnt->mnt_dir, PATH_MAX);
- strncpy(devname, mnt->mnt_fsname, strlen(mnt->mnt_fsname) + 1);
+ strncpy(devname, mnt->mnt_fsname, PATH_MAX);
}
endmntent(fp);
- if (mnt_type && strcmp(mnt_type, FS_EXT4) == 0) {
- FREE(mnt_type);
+ if (type_is_ext4)
return 0;
- } else {
- FREE(mnt_type);
- PRINT_ERR_MSG(NGMSG_EXT4);
- return -1;
- }
+ PRINT_ERR_MSG(NGMSG_EXT4);
+ return -1;
}
/*
@@ -1865,11 +1855,9 @@ int main(int argc, char *argv[])
/* fall through */
case DEVNAME:
if (arg_type == DEVNAME) {
- strncpy(lost_found_dir, dir_name,
- strnlen(dir_name, PATH_MAX));
+ strcpy(lost_found_dir, dir_name);
strncat(lost_found_dir, "/lost+found/",
- PATH_MAX - strnlen(lost_found_dir,
- PATH_MAX));
+ PATH_MAX - strlen(lost_found_dir));
}
nftw64(dir_name, calc_entry_counts, FTW_OPEN_FD, flags);
--
2.39.0
