On 6/2/20 7:27 AM, Richard W.M. Jones wrote:
Use an extensible buffer (a vector<char>) when reading
/proc/self/cmdline.
Tidy up some error messages.
---
plugins/vddk/reexec.c | 57 ++++++++++++++++++++++++++-----------------
1 file changed, 35 insertions(+), 22 deletions(-)
@@ -80,42 +95,40 @@ perform_reexec (const char *env, const char *prepend)
* until we get a short read. This assumes nbdkit did not alter its
* original argv[].
*/
- fd = open ("/proc/self/cmdline", O_RDONLY);
+ fd = open (cmdline_file, O_RDONLY|O_CLOEXEC);
if (fd == -1) {
- nbdkit_debug ("failure to parse original argv: %m");
+ nbdkit_debug ("open: %s: %m", cmdline_file);
return;
}
- do {
- char *p = realloc (buf, buflen * 2);
+ for (;;) {
ssize_t r;
- if (!p) {
- nbdkit_debug ("failure to parse original argv: %m");
+ if (buffer_reserve (&buf, 512) == -1) {
+ nbdkit_debug ("realloc: %m");
return;
}
Pre-existing bug, which you did not fix here. If we failed here, we are
leaking fd. You slightly improved the situation by marking the leaked
fd O_CLOEXEC, but that really doesn't matter if we properly fix the code
to close(fd) before any early return, at which point the lifetime of fd
is only during single-threaded execution and O_CLOEXEC doesn't matter.
Rest of the patch looks fine.
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3226
Virtualization: qemu.org | libvirt.org
_______________________________________________
Libguestfs mailing list
[email protected]
https://www.redhat.com/mailman/listinfo/libguestfs
