| Message ID | 20170619050537.6393-1-gvaradar@cisco.com |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | David Miller |
| Headers | show |
On Sun, 2017-06-18 at 22:05 -0700, Govindarajulu Varadarajan wrote: > With -Wformat-truncation=, gcc throws the following warning. Instead of > using snprintf, use kasprintf and allocate string size as needed. > > drivers/net/ethernet/cisco/enic/enic_main.c: In function ‘enic_open’: > drivers/net/ethernet/cisco/enic/enic_main.c:1740:15: warning: ‘%u’ directive output may be truncated writing between 1 and 2 bytes into a region of size between 1 and 12 [-Wformat-truncation=] > "%.11s-rx-%u", netdev->name, i); > ^~ > drivers/net/ethernet/cisco/enic/enic_main.c:1740:5: note: directive argument in the range [0, 16] > "%.11s-rx-%u", netdev->name, i); > ^~~~~~~~~~~~~ > drivers/net/ethernet/cisco/enic/enic_main.c:1738:4: note: ‘snprintf’ output between 6 and 18 bytes into a destination of size 16 > snprintf(enic->msix[intr].devname, > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > sizeof(enic->msix[intr].devname), > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > "%.11s-rx-%u", netdev->name, i); > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > drivers/net/ethernet/cisco/enic/enic_main.c:1751:5: warning: ‘snprintf’ output may be truncated before the last format character [-Wformat-truncation=] > "%.11s-tx-%u", netdev->name, i); Perhaps it'd be better to use a style with a variable length format precision ie: "%.*s-tx-%u", IFNAMSIZ - 4 - <something>, netdev-name, i)
On Sun, 18 Jun 2017, Joe Perches wrote: > Perhaps it'd be better to use a style > with a variable length format precision > > ie: > > "%.*s-tx-%u", IFNAMSIZ - 4 - <something>, netdev-name, i) > This would truncate interface name. Why is this preferred to my patch?
On Sun, 2017-06-18 at 22:55 -0700, Govindarajulu Varadarajan wrote: > On Sun, 18 Jun 2017, Joe Perches wrote: > > > Perhaps it'd be better to use a style > > with a variable length format precision > > > > ie: > > > > "%.*s-tx-%u", IFNAMSIZ - 4 - <something>, netdev-name, i) > > > > This would truncate interface name. Why is this preferred to my patch? no allocation required, simpler.
From: Govindarajulu Varadarajan <gvaradar@cisco.com> Date: Sun, 18 Jun 2017 22:05:37 -0700 > With -Wformat-truncation=, gcc throws the following warning. Instead of > using snprintf, use kasprintf and allocate string size as needed. > > drivers/net/ethernet/cisco/enic/enic_main.c: In function ‘enic_open’: > drivers/net/ethernet/cisco/enic/enic_main.c:1740:15: warning: ‘%u’ directive output may be truncated writing between 1 and 2 bytes into a region of size between 1 and 12 [-Wformat-truncation=] > "%.11s-rx-%u", netdev->name, i); > ^~ > drivers/net/ethernet/cisco/enic/enic_main.c:1740:5: note: directive argument in the range [0, 16] > "%.11s-rx-%u", netdev->name, i); > ^~~~~~~~~~~~~ > drivers/net/ethernet/cisco/enic/enic_main.c:1738:4: note: ‘snprintf’ output between 6 and 18 bytes into a destination of size 16 > snprintf(enic->msix[intr].devname, > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > sizeof(enic->msix[intr].devname), > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > "%.11s-rx-%u", netdev->name, i); > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > drivers/net/ethernet/cisco/enic/enic_main.c:1751:5: warning: ‘snprintf’ output may be truncated before the last format character [-Wformat-truncation=] > "%.11s-tx-%u", netdev->name, i); > ^~~~~~~~~~~~~ > > also increment the version. > > Signed-off-by: Govindarajulu Varadarajan <gvaradar@cisco.com> Using dynamic allocation is overkill for this problem.
diff --git a/drivers/net/ethernet/cisco/enic/enic.h b/drivers/net/ethernet/cisco/enic/enic.h index 2b23f46b34d3..b8de2813119f 100644 --- a/drivers/net/ethernet/cisco/enic/enic.h +++ b/drivers/net/ethernet/cisco/enic/enic.h @@ -33,7 +33,7 @@ #define DRV_NAME "enic" #define DRV_DESCRIPTION "Cisco VIC Ethernet NIC Driver" -#define DRV_VERSION "2.3.0.31" +#define DRV_VERSION "2.3.0.42" #define DRV_COPYRIGHT "Copyright 2008-2013 Cisco Systems, Inc" #define ENIC_BARS_MAX 6 @@ -47,7 +47,7 @@ struct enic_msix_entry { int requested; - char devname[IFNAMSIZ]; + char *devname; irqreturn_t (*isr)(int, void *); void *devid; cpumask_var_t affinity_mask; diff --git a/drivers/net/ethernet/cisco/enic/enic_main.c b/drivers/net/ethernet/cisco/enic/enic_main.c index 6a9c8878aca0..11b79f26af75 100644 --- a/drivers/net/ethernet/cisco/enic/enic_main.c +++ b/drivers/net/ethernet/cisco/enic/enic_main.c @@ -1701,9 +1701,11 @@ static void enic_free_intr(struct enic *enic) break; case VNIC_DEV_INTR_MODE_MSIX: for (i = 0; i < ARRAY_SIZE(enic->msix); i++) - if (enic->msix[i].requested) + if (enic->msix[i].requested) { free_irq(enic->msix_entry[i].vector, enic->msix[i].devid); + kfree(enic->msix[i].devname); + } break; default: break; @@ -1735,9 +1737,12 @@ static int enic_request_intr(struct enic *enic) for (i = 0; i < enic->rq_count; i++) { intr = enic_msix_rq_intr(enic, i); - snprintf(enic->msix[intr].devname, - sizeof(enic->msix[intr].devname), - "%.11s-rx-%u", netdev->name, i); + enic->msix[intr].devname = kasprintf(GFP_KERNEL, + "%s-rx-%u", + netdev->name, i); + if (!enic->msix[intr].devname) + netdev_warn(netdev, "name alloc failed for intr %d", + intr); enic->msix[intr].isr = enic_isr_msix; enic->msix[intr].devid = &enic->napi[i]; } @@ -1746,24 +1751,31 @@ static int enic_request_intr(struct enic *enic) int wq = enic_cq_wq(enic, i); intr = enic_msix_wq_intr(enic, i); - snprintf(enic->msix[intr].devname, - sizeof(enic->msix[intr].devname), - "%.11s-tx-%u", netdev->name, i); + enic->msix[intr].devname = kasprintf(GFP_KERNEL, + "%s-tx-%u", + netdev->name, i); + if (!enic->msix[intr].devname) + netdev_warn(netdev, "name alloc failed for intr %d", + intr); enic->msix[intr].isr = enic_isr_msix; enic->msix[intr].devid = &enic->napi[wq]; } intr = enic_msix_err_intr(enic); - snprintf(enic->msix[intr].devname, - sizeof(enic->msix[intr].devname), - "%.11s-err", netdev->name); + enic->msix[intr].devname = kasprintf(GFP_KERNEL, "%s-err", + netdev->name); + if (!enic->msix[intr].devname) + netdev_warn(netdev, "name alloc failed for intr %d", + intr); enic->msix[intr].isr = enic_isr_msix_err; enic->msix[intr].devid = enic; intr = enic_msix_notify_intr(enic); - snprintf(enic->msix[intr].devname, - sizeof(enic->msix[intr].devname), - "%.11s-notify", netdev->name); + enic->msix[intr].devname = kasprintf(GFP_KERNEL, "%s-notify", + netdev->name); + if (!enic->msix[intr].devname) + netdev_warn(netdev, "name alloc failed for intr %d", + intr); enic->msix[intr].isr = enic_isr_msix_notify; enic->msix[intr].devid = enic;
With -Wformat-truncation=, gcc throws the following warning. Instead of using snprintf, use kasprintf and allocate string size as needed. drivers/net/ethernet/cisco/enic/enic_main.c: In function ‘enic_open’: drivers/net/ethernet/cisco/enic/enic_main.c:1740:15: warning: ‘%u’ directive output may be truncated writing between 1 and 2 bytes into a region of size between 1 and 12 [-Wformat-truncation=] "%.11s-rx-%u", netdev->name, i); ^~ drivers/net/ethernet/cisco/enic/enic_main.c:1740:5: note: directive argument in the range [0, 16] "%.11s-rx-%u", netdev->name, i); ^~~~~~~~~~~~~ drivers/net/ethernet/cisco/enic/enic_main.c:1738:4: note: ‘snprintf’ output between 6 and 18 bytes into a destination of size 16 snprintf(enic->msix[intr].devname, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ sizeof(enic->msix[intr].devname), ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ "%.11s-rx-%u", netdev->name, i); ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/net/ethernet/cisco/enic/enic_main.c:1751:5: warning: ‘snprintf’ output may be truncated before the last format character [-Wformat-truncation=] "%.11s-tx-%u", netdev->name, i); ^~~~~~~~~~~~~ also increment the version. Signed-off-by: Govindarajulu Varadarajan <gvaradar@cisco.com> --- drivers/net/ethernet/cisco/enic/enic.h | 4 +-- drivers/net/ethernet/cisco/enic/enic_main.c | 38 +++++++++++++++++++---------- 2 files changed, 27 insertions(+), 15 deletions(-)