| Message ID | 1375879333-17487-1-git-send-email-colin.king@canonical.com |
|---|---|
| State | Accepted |
| Headers | show |
On Wed, Aug 7, 2013 at 8:42 PM, Colin King <colin.king@canonical.com> wrote: > From: Colin Ian King <colin.king@canonical.com> > > Coverity Scan reports that the stat/open may give a small window > of opportunity for a stat/open race condition. So just forget the > stat as open will do. > > Signed-off-by: Colin Ian King <colin.king@canonical.com> > --- > src/lib/src/fwts_cpu.c | 13 +++---------- > 1 file changed, 3 insertions(+), 10 deletions(-) > > diff --git a/src/lib/src/fwts_cpu.c b/src/lib/src/fwts_cpu.c > index 44711fd..fc52fa5 100644 > --- a/src/lib/src/fwts_cpu.c > +++ b/src/lib/src/fwts_cpu.c > @@ -51,30 +51,23 @@ static pid_t *fwts_cpu_pids; > */ > int fwts_cpu_readmsr(const int cpu, const uint32_t reg, uint64_t *val) > { > - struct stat statbuf; > char buffer[PATH_MAX]; > - uint64_t value; > + uint64_t value = 0; > int fd; > int ret; > > - value = 0; > - > snprintf(buffer, sizeof(buffer), "/dev/cpu/%d/msr", cpu); > - > - if (stat(buffer, &statbuf)) { > + if ((fd = open(buffer, O_RDONLY)) < 0) { > /* Hrm, msr not there, so force modprobe msr and see what happens */ > pid_t pid; > if ((fd = fwts_pipe_open("modprobe msr", &pid)) < 0) > return FWTS_ERROR; > fwts_pipe_close(fd, pid); > > - if (stat(buffer, &statbuf)) > + if ((fd = open(buffer, O_RDONLY)) < 0) > return FWTS_ERROR; /* Really failed */ > } > > - if ((fd = open(buffer, O_RDONLY)) < 0) > - return FWTS_ERROR; > - > ret = pread(fd, &value, 8, reg); > close(fd); > > -- > 1.8.3.2 > Acked-by: Keng-Yu Lin <kengyu@canonical.com>
On 08/07/2013 08:42 PM, Colin King wrote: > From: Colin Ian King <colin.king@canonical.com> > > Coverity Scan reports that the stat/open may give a small window > of opportunity for a stat/open race condition. So just forget the > stat as open will do. > > Signed-off-by: Colin Ian King <colin.king@canonical.com> > --- > src/lib/src/fwts_cpu.c | 13 +++---------- > 1 file changed, 3 insertions(+), 10 deletions(-) > > diff --git a/src/lib/src/fwts_cpu.c b/src/lib/src/fwts_cpu.c > index 44711fd..fc52fa5 100644 > --- a/src/lib/src/fwts_cpu.c > +++ b/src/lib/src/fwts_cpu.c > @@ -51,30 +51,23 @@ static pid_t *fwts_cpu_pids; > */ > int fwts_cpu_readmsr(const int cpu, const uint32_t reg, uint64_t *val) > { > - struct stat statbuf; > char buffer[PATH_MAX]; > - uint64_t value; > + uint64_t value = 0; > int fd; > int ret; > > - value = 0; > - > snprintf(buffer, sizeof(buffer), "/dev/cpu/%d/msr", cpu); > - > - if (stat(buffer, &statbuf)) { > + if ((fd = open(buffer, O_RDONLY)) < 0) { > /* Hrm, msr not there, so force modprobe msr and see what happens */ > pid_t pid; > if ((fd = fwts_pipe_open("modprobe msr", &pid)) < 0) > return FWTS_ERROR; > fwts_pipe_close(fd, pid); > > - if (stat(buffer, &statbuf)) > + if ((fd = open(buffer, O_RDONLY)) < 0) > return FWTS_ERROR; /* Really failed */ > } > > - if ((fd = open(buffer, O_RDONLY)) < 0) > - return FWTS_ERROR; > - > ret = pread(fd, &value, 8, reg); > close(fd); > > Acked-by: Alex Hung <alex.hung@canonical.com>
diff --git a/src/lib/src/fwts_cpu.c b/src/lib/src/fwts_cpu.c index 44711fd..fc52fa5 100644 --- a/src/lib/src/fwts_cpu.c +++ b/src/lib/src/fwts_cpu.c @@ -51,30 +51,23 @@ static pid_t *fwts_cpu_pids; */ int fwts_cpu_readmsr(const int cpu, const uint32_t reg, uint64_t *val) { - struct stat statbuf; char buffer[PATH_MAX]; - uint64_t value; + uint64_t value = 0; int fd; int ret; - value = 0; - snprintf(buffer, sizeof(buffer), "/dev/cpu/%d/msr", cpu); - - if (stat(buffer, &statbuf)) { + if ((fd = open(buffer, O_RDONLY)) < 0) { /* Hrm, msr not there, so force modprobe msr and see what happens */ pid_t pid; if ((fd = fwts_pipe_open("modprobe msr", &pid)) < 0) return FWTS_ERROR; fwts_pipe_close(fd, pid); - if (stat(buffer, &statbuf)) + if ((fd = open(buffer, O_RDONLY)) < 0) return FWTS_ERROR; /* Really failed */ } - if ((fd = open(buffer, O_RDONLY)) < 0) - return FWTS_ERROR; - ret = pread(fd, &value, 8, reg); close(fd);