diff options
authorJesper Juhl <>2010-12-24 21:28:56 +0100
committerMichal Marek <>2010-12-29 15:06:54 +0100
commit96aebafa63418f447ddc823e40da341cc40553dd (patch)
parent731ece41fb1047816303295a0cdfed90a528137e (diff)
gen_init_cpio: Avoid race between call to stat() and call to open()
In usr/gen_init_cpio.c::cpio_mkfile() a call to stat() is made based on pathname, subsequently the file is open()'ed and then the value of the initial stat() call is used to allocate a buffer. This is not safe since the file may change between the call to stat() and the call to open(). Safer to just open() the file and then do fstat() using the filedescriptor returned by open. Signed-off-by: Jesper Juhl <> Acked-by: Jeff Garzik <> Signed-off-by: Michal Marek <>
1 files changed, 6 insertions, 6 deletions
diff --git a/usr/gen_init_cpio.c b/usr/gen_init_cpio.c
index 59df70d9d1dc..f463cafdccb2 100644
--- a/usr/gen_init_cpio.c
+++ b/usr/gen_init_cpio.c
@@ -309,18 +309,18 @@ static int cpio_mkfile(const char *name, const char *location,
mode |= S_IFREG;
- retval = stat (location, &buf);
- if (retval) {
- fprintf (stderr, "File %s could not be located\n", location);
- goto error;
- }
file = open (location, O_RDONLY);
if (file < 0) {
fprintf (stderr, "File %s could not be opened for reading\n", location);
goto error;
+ retval = fstat (file, &buf);
+ if (retval) {
+ fprintf (stderr, "File %s could not be stat()'ed\n", location);
+ goto error;
+ }
filebuf = malloc(buf.st_size);
if (!filebuf) {
fprintf (stderr, "out of memory\n");