At Tue, 06 May 2014 16:53:00 +0200, Jaroslav Kysela wrote:
Date 6.5.2014 13:57, Julian Scheel wrote:
It can not be generally assumed that the directories in which asound.state resides are writable. Instead using /tmp as location for lock files seems more reliable.
Apart the missing free for the mallocated string and ommiting the TMPDIR environment variable, I think that the right directory for global locks is /var/lock . The default asound.state directory is now /var/lib/alsa - I don't see the benefit.
Agreed. Above all, using a fixed path with /tmp is really fragile, easily leading to a security risk for a service that is run by root like this.
What's the reason for this change? Perhaps using an environmental variable to override the lock path may be more appropriate for a custom directory structure.
... or give an option?
Takashi
Jaroslav
Signed-off-by: Julian Scheel julian@jusst.de
alsactl/lock.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/alsactl/lock.c b/alsactl/lock.c index 587a109..7ca3a09 100644 --- a/alsactl/lock.c +++ b/alsactl/lock.c @@ -36,17 +36,24 @@ static int state_lock_(const char *file, int lock, int timeout) struct flock lck; struct stat st; char lcktxt[12];
char *filename; char *nfile;
if (!do_lock) return 0;
- nfile = malloc(strlen(file) + 6);
- /* only use the actual filename, not the path */
- filename = strrchr(file, '/');
- if (!filename)
filename = file;
- nfile = malloc(strlen(filename) + 10); if (nfile == NULL) { error("No enough memory..."); return -ENOMEM; }
- strcpy(nfile, file);
- strcat(nfile, ".lock");
- sprintf(nfile, "/tmp/%s.lock", filename); lck.l_type = lock ? F_WRLCK : F_UNLCK; lck.l_whence = SEEK_SET; lck.l_start = 0;
-- Jaroslav Kysela perex@perex.cz Linux Kernel Sound Maintainer ALSA Project; Red Hat, Inc. _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org http://mailman.alsa-project.org/mailman/listinfo/alsa-devel