Messages in this thread Patch in this message | | | Date | Mon, 16 Nov 2009 17:55:33 +0100 | From | Roel Kluin <> | Subject | [PATCH] Documentation: Fix NUL termination of strncpy |
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Ensure the copied strings are NUL terminated.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com> --- Documentation/accounting/getdelays.c | 2 +- Documentation/hwmon/hpfall.c | 2 +- Documentation/networking/radiotap-headers.txt | 2 +- .../networking/timestamping/timestamping.c | 4 ++-- 4 files changed, 5 insertions(+), 5 deletions(-)
Rationale (please correct me if I'm wrong):
For a larger source string, strncpy only NUL terminates when the size argument is _less_ than sizeof(destination string). strlcpy does this when it equals sizeof (dest), but does not overwrite NULs in the higher chars.
Because cpumask is global I used strncpy, for the extra NULs. devname is local so I think strlcpy can be used. For {device,hwtstamp}.ifr_name I thought the strlcpy could be used since ifr_name is zeroed upon creation of device and hwtstamp.
Oh, and the parenthesis in radiotap-headers.txt should not be there.
Roel
diff --git a/Documentation/accounting/getdelays.c b/Documentation/accounting/getdelays.c index 6e25c26..4d71b0e 100644 --- a/Documentation/accounting/getdelays.c +++ b/Documentation/accounting/getdelays.c @@ -303,7 +303,7 @@ int main(int argc, char *argv[]) err(1, "Invalid rcv buf size\n"); break; case 'm': - strncpy(cpumask, optarg, sizeof(cpumask)); + strncpy(cpumask, optarg, sizeof(cpumask) - 1); maskset = 1; printf("cpumask %s maskset %d\n", cpumask, maskset); break; diff --git a/Documentation/hwmon/hpfall.c b/Documentation/hwmon/hpfall.c index 681ec22..00477ea 100644 --- a/Documentation/hwmon/hpfall.c +++ b/Documentation/hwmon/hpfall.c @@ -27,7 +27,7 @@ int set_unload_heads_path(char *device) if (strlen(device) <= 5 || strncmp(device, "/dev/", 5) != 0) return -EINVAL; - strncpy(devname, device + 5, sizeof(devname)); + strlcpy(devname, device + 5, sizeof(devname)); snprintf(unload_heads_path, sizeof(unload_heads_path), "/sys/block/%s/device/unload_heads", devname); diff --git a/Documentation/networking/radiotap-headers.txt b/Documentation/networking/radiotap-headers.txt index 953331c..447e004 100644 --- a/Documentation/networking/radiotap-headers.txt +++ b/Documentation/networking/radiotap-headers.txt @@ -126,7 +126,7 @@ int MyFunction(u8 * buf, int buflen) case IEEE80211_RADIOTAP_ANTENNA: /* radiotap uses 0 for 1st ant */ - antenna = *iterator.this_arg); + antenna = *iterator.this_arg; break; case IEEE80211_RADIOTAP_DBM_TX_POWER: diff --git a/Documentation/networking/timestamping/timestamping.c b/Documentation/networking/timestamping/timestamping.c index a7936fe..c1acd2c 100644 --- a/Documentation/networking/timestamping/timestamping.c +++ b/Documentation/networking/timestamping/timestamping.c @@ -374,12 +374,12 @@ int main(int argc, char **argv) bail("socket"); memset(&device, 0, sizeof(device)); - strncpy(device.ifr_name, interface, sizeof(device.ifr_name)); + strlcpy(device.ifr_name, interface, sizeof(device.ifr_name)); if (ioctl(sock, SIOCGIFADDR, &device) < 0) bail("getting interface IP address"); memset(&hwtstamp, 0, sizeof(hwtstamp)); - strncpy(hwtstamp.ifr_name, interface, sizeof(hwtstamp.ifr_name)); + strlcpy(hwtstamp.ifr_name, interface, sizeof(hwtstamp.ifr_name)); hwtstamp.ifr_data = (void *)&hwconfig; memset(&hwconfig, 0, sizeof(hwconfig)); hwconfig.tx_type =
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