Subject: + clean-up-scary-strncpydst-src-strlensrc-uses.patch added to -mm tree To: keescook@xxxxxxxxxxxx,blaschka@xxxxxxxxxxxxxxxxxx,gregkh@xxxxxxxxxxxxxxxxxxx,heiko.carstens@xxxxxxxxxx,rafael.j.wysocki@xxxxxxxxx,richard@xxxxxx,schwidefsky@xxxxxxxxxx,ursula.braun@xxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Mon, 03 Jun 2013 15:22:15 -0700 The patch titled Subject: clean up scary strncpy(dst, src, strlen(src)) uses has been added to the -mm tree. Its filename is clean-up-scary-strncpydst-src-strlensrc-uses.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Kees Cook <keescook@xxxxxxxxxxxx> Subject: clean up scary strncpy(dst, src, strlen(src)) uses Fix various weird constructions of strncpy(dst, src, strlen(src)). Length limits should be about the space available in the destination, not repurposed as a method to either always include or always exclude a trailing NULL byte. Either the NULL should always be copied (using strlcpy), or it should not be copied (using something like memcpy). Readable code should not depend on the weird behavior of strncpy when it hits the length limit. Better to avoid the anti-pattern entirely. Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Acked-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> [staging] Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> [acpi] Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx> Cc: Ursula Braun <ursula.braun@xxxxxxxxxx> Cc: Frank Blaschka <blaschka@xxxxxxxxxxxxxxxxxx> Cc: Richard Weinberger <richard@xxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- Documentation/accounting/getdelays.c | 3 ++- drivers/acpi/sysfs.c | 3 +-- drivers/s390/net/qeth_l3_sys.c | 6 ++---- drivers/staging/tidspbridge/rmgr/drv_interface.c | 3 +-- fs/hppfs/hppfs.c | 11 ++++++----- 5 files changed, 12 insertions(+), 14 deletions(-) diff -puN Documentation/accounting/getdelays.c~clean-up-scary-strncpydst-src-strlensrc-uses Documentation/accounting/getdelays.c --- a/Documentation/accounting/getdelays.c~clean-up-scary-strncpydst-src-strlensrc-uses +++ a/Documentation/accounting/getdelays.c @@ -23,6 +23,7 @@ #include <sys/socket.h> #include <sys/wait.h> #include <signal.h> +#include <bsd/string.h> #include <linux/genetlink.h> #include <linux/taskstats.h> @@ -299,7 +300,7 @@ int main(int argc, char *argv[]) break; case 'C': containerset = 1; - strncpy(containerpath, optarg, strlen(optarg) + 1); + strlcpy(containerpath, optarg, sizeof(containerpath)); break; case 'w': logfile = strdup(optarg); diff -puN drivers/acpi/sysfs.c~clean-up-scary-strncpydst-src-strlensrc-uses drivers/acpi/sysfs.c --- a/drivers/acpi/sysfs.c~clean-up-scary-strncpydst-src-strlensrc-uses +++ a/drivers/acpi/sysfs.c @@ -677,10 +677,9 @@ void acpi_irq_stats_init(void) else sprintf(buffer, "bug%02X", i); - name = kzalloc(strlen(buffer) + 1, GFP_KERNEL); + name = kstrdup(buffer, GFP_KERNEL); if (name == NULL) goto fail; - strncpy(name, buffer, strlen(buffer) + 1); sysfs_attr_init(&counter_attrs[i].attr); counter_attrs[i].attr.name = name; diff -puN drivers/s390/net/qeth_l3_sys.c~clean-up-scary-strncpydst-src-strlensrc-uses drivers/s390/net/qeth_l3_sys.c --- a/drivers/s390/net/qeth_l3_sys.c~clean-up-scary-strncpydst-src-strlensrc-uses +++ a/drivers/s390/net/qeth_l3_sys.c @@ -315,10 +315,8 @@ static ssize_t qeth_l3_dev_hsuid_store(s if (qeth_configure_cq(card, QETH_CQ_ENABLED)) return -EPERM; - for (i = 0; i < 8; i++) - card->options.hsuid[i] = ' '; - card->options.hsuid[8] = '\0'; - strncpy(card->options.hsuid, tmp, strlen(tmp)); + snprintf(card->options.hsuid, sizeof(card->options.hsuid), + "%-8s", tmp); ASCEBC(card->options.hsuid, 8); if (card->dev) memcpy(card->dev->perm_addr, card->options.hsuid, 9); diff -puN drivers/staging/tidspbridge/rmgr/drv_interface.c~clean-up-scary-strncpydst-src-strlensrc-uses drivers/staging/tidspbridge/rmgr/drv_interface.c --- a/drivers/staging/tidspbridge/rmgr/drv_interface.c~clean-up-scary-strncpydst-src-strlensrc-uses +++ a/drivers/staging/tidspbridge/rmgr/drv_interface.c @@ -421,12 +421,11 @@ static int omap3_bridge_startup(struct p drv_datap->tc_wordswapon = tc_wordswapon; if (base_img) { - drv_datap->base_img = kmalloc(strlen(base_img) + 1, GFP_KERNEL); + drv_datap->base_img = kstrdup(base_img, GFP_KERNEL); if (!drv_datap->base_img) { err = -ENOMEM; goto err2; } - strncpy(drv_datap->base_img, base_img, strlen(base_img) + 1); } dev_set_drvdata(bridge, drv_datap); diff -puN fs/hppfs/hppfs.c~clean-up-scary-strncpydst-src-strlensrc-uses fs/hppfs/hppfs.c --- a/fs/hppfs/hppfs.c~clean-up-scary-strncpydst-src-strlensrc-uses +++ a/fs/hppfs/hppfs.c @@ -69,7 +69,7 @@ static char *dentry_name(struct dentry * struct dentry *parent; char *root, *name; const char *seg_name; - int len, seg_len; + int len, seg_len, root_len; len = 0; parent = dentry; @@ -81,7 +81,8 @@ static char *dentry_name(struct dentry * } root = "proc"; - len += strlen(root); + root_len = strlen(root); + len += root_len; name = kmalloc(len + extra + 1, GFP_KERNEL); if (name == NULL) return NULL; @@ -91,7 +92,7 @@ static char *dentry_name(struct dentry * while (parent->d_parent != parent) { if (is_pid(parent)) { seg_name = "pid"; - seg_len = strlen("pid"); + seg_len = strlen(seg_name); } else { seg_name = parent->d_name.name; @@ -100,10 +101,10 @@ static char *dentry_name(struct dentry * len -= seg_len + 1; name[len] = '/'; - strncpy(&name[len + 1], seg_name, seg_len); + memcpy(&name[len + 1], seg_name, seg_len); parent = parent->d_parent; } - strncpy(name, root, strlen(root)); + memcpy(name, root, root_len); return name; } _ Patches currently in -mm which might be from keescook@xxxxxxxxxxxx are origin.patch kmsg-honor-dmesg_restrict-sysctl-on-dev-kmsg.patch kmsg-honor-dmesg_restrict-sysctl-on-dev-kmsg-fix.patch drivers-mtd-chips-gen_probec-refactor-call-to-request_module.patch clean-up-scary-strncpydst-src-strlensrc-uses.patch binfmt_elfc-use-get_random_int-to-fix-entropy-depleting.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html