| Message ID | 20170104150525.4246-1-pbonzini@redhat.com |
|---|---|
| State | New |
| Headers | show |
On 01/04/2017 09:05 AM, Paolo Bonzini wrote: > Just check the errno value after fopen and follow it with fstat. > This shuts up Coverity's complaint about TOC/TOU violation. > > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> > --- > hw/i386/pci-assign-load-rom.c | 16 ++++++++-------- > 1 file changed, 8 insertions(+), 8 deletions(-) Reviewed-by: Eric Blake <eblake@redhat.com> > > diff --git a/hw/i386/pci-assign-load-rom.c b/hw/i386/pci-assign-load-rom.c > index 0d8e4b2..fd59076 100644 > --- a/hw/i386/pci-assign-load-rom.c > +++ b/hw/i386/pci-assign-load-rom.c > @@ -39,19 +39,19 @@ void *pci_assign_dev_load_option_rom(PCIDevice *dev, struct Object *owner, > "/sys/bus/pci/devices/%04x:%02x:%02x.%01x/rom", > domain, bus, slot, function); > > - if (stat(rom_file, &st)) { > - if (errno != ENOENT) { > - error_report("pci-assign: Invalid ROM."); > - } > - return NULL; > - } > - > /* Write "1" to the ROM file to enable it */ > fp = fopen(rom_file, "r+"); > if (fp == NULL) { > - error_report("pci-assign: Cannot open %s: %s", rom_file, strerror(errno)); > + if (errno != ENOENT) { > + error_report("pci-assign: Cannot open %s: %s", rom_file, strerror(errno)); > + } > return NULL; > } > + if (fstat(fileno(fp), &st) == -1) { > + error_report("pci-assign: Cannot stat %s: %s", rom_file, strerror(errno)); > + goto close_rom; fstat() failure after fopen() success is quite unlikely, but I suppose it is still possible in some weird situations.
04.01.2017 18:05, Paolo Bonzini wrote: > Just check the errno value after fopen and follow it with fstat. > This shuts up Coverity's complaint about TOC/TOU violation. Applied to -trivial, thanks! /mjt
diff --git a/hw/i386/pci-assign-load-rom.c b/hw/i386/pci-assign-load-rom.c index 0d8e4b2..fd59076 100644 --- a/hw/i386/pci-assign-load-rom.c +++ b/hw/i386/pci-assign-load-rom.c @@ -39,19 +39,19 @@ void *pci_assign_dev_load_option_rom(PCIDevice *dev, struct Object *owner, "/sys/bus/pci/devices/%04x:%02x:%02x.%01x/rom", domain, bus, slot, function); - if (stat(rom_file, &st)) { - if (errno != ENOENT) { - error_report("pci-assign: Invalid ROM."); - } - return NULL; - } - /* Write "1" to the ROM file to enable it */ fp = fopen(rom_file, "r+"); if (fp == NULL) { - error_report("pci-assign: Cannot open %s: %s", rom_file, strerror(errno)); + if (errno != ENOENT) { + error_report("pci-assign: Cannot open %s: %s", rom_file, strerror(errno)); + } return NULL; } + if (fstat(fileno(fp), &st) == -1) { + error_report("pci-assign: Cannot stat %s: %s", rom_file, strerror(errno)); + goto close_rom; + } + val = 1; if (fwrite(&val, 1, 1, fp) != 1) { goto close_rom;
Just check the errno value after fopen and follow it with fstat. This shuts up Coverity's complaint about TOC/TOU violation. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> --- hw/i386/pci-assign-load-rom.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-)