[PATCH 0/9] enabled -Wformat-truncation for clang
From: Arnd Bergmann arnd@arndb.de
With randconfig build testing, I found only eight files that produce warnings with clang when -Wformat-truncation is enabled. This means we can just turn it on by default rather than only enabling it for "make W=1".
Unfortunately, gcc produces a lot more warnings when the option is enabled, so it's not yet possible to turn it on both both compilers.
I hope that the patches can get picked up by platform maintainers directly, so the final patch can go in later on.
Arnd
Arnd Bergmann (9): fbdev: shmobile: fix snprintf truncation enetc: avoid truncating error message qed: avoid truncating work queue length mlx5: avoid truncating error message surface3_power: avoid format string truncation warning Input: IMS: fix printf string overflow scsi: mylex: fix sysfs buffer lengths ALSA: aoa: avoid false-positive format truncation warning kbuild: enable -Wformat-truncation on clang
drivers/input/misc/ims-pcu.c | 4 ++-- drivers/net/ethernet/freescale/enetc/enetc.c | 2 +- .../ethernet/mellanox/mlx5/core/esw/bridge.c | 2 +- drivers/net/ethernet/qlogic/qed/qed_main.c | 9 ++++--- drivers/platform/surface/surface3_power.c | 2 +- drivers/scsi/myrb.c | 20 ++++++++-------- drivers/scsi/myrs.c | 24 +++++++++---------- drivers/video/fbdev/sh_mobile_lcdcfb.c | 2 +- scripts/Makefile.extrawarn | 2 ++ sound/aoa/soundbus/i2sbus/core.c | 2 +- 10 files changed, 35 insertions(+), 34 deletions(-)
From: Arnd Bergmann arnd@arndb.de
clang warns about what it interprets as a truncated snprintf:
sound/aoa/soundbus/i2sbus/core.c:171:6: error: 'snprintf' will always be truncated; specified size is 6, but format string expands to at least 7 [-Werror,-Wformat-truncation-non-kprintf]
The actual problem here is that it does not understand the special %pOFn format string and assumes that it is a pointer followed by the string "OFn", which would indeed not fit.
Slightly increasing the size of the buffer to its natural alignment avoids the warning, as it is now long enough for the correct and the incorrect interprations.
Fixes: b917d58dcfaa ("ALSA: aoa: Convert to using %pOFn instead of device_node.name") Signed-off-by: Arnd Bergmann arnd@arndb.de --- sound/aoa/soundbus/i2sbus/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/sound/aoa/soundbus/i2sbus/core.c b/sound/aoa/soundbus/i2sbus/core.c index b8ff5cccd0c8..5431d2c49421 100644 --- a/sound/aoa/soundbus/i2sbus/core.c +++ b/sound/aoa/soundbus/i2sbus/core.c @@ -158,7 +158,7 @@ static int i2sbus_add_dev(struct macio_dev *macio, struct device_node *child, *sound = NULL; struct resource *r; int i, layout = 0, rlen, ok = force; - char node_name[6]; + char node_name[8]; static const char *rnames[] = { "i2sbus: %pOFn (control)", "i2sbus: %pOFn (tx)", "i2sbus: %pOFn (rx)" };
On Tue, 26 Mar 2024 23:38:07 +0100, Arnd Bergmann wrote:
From: Arnd Bergmann arnd@arndb.de
clang warns about what it interprets as a truncated snprintf:
sound/aoa/soundbus/i2sbus/core.c:171:6: error: 'snprintf' will always be truncated; specified size is 6, but format string expands to at least 7 [-Werror,-Wformat-truncation-non-kprintf]
The actual problem here is that it does not understand the special %pOFn format string and assumes that it is a pointer followed by the string "OFn", which would indeed not fit.
Slightly increasing the size of the buffer to its natural alignment avoids the warning, as it is now long enough for the correct and the incorrect interprations.
Fixes: b917d58dcfaa ("ALSA: aoa: Convert to using %pOFn instead of device_node.name") Signed-off-by: Arnd Bergmann arnd@arndb.de
Applied this one now to sound.git tree. Thanks.
Takashi
Hello:
This series was applied to netdev/net-next.git (main) by Jakub Kicinski kuba@kernel.org:
On Tue, 26 Mar 2024 23:37:59 +0100 you wrote:
From: Arnd Bergmann arnd@arndb.de
With randconfig build testing, I found only eight files that produce warnings with clang when -Wformat-truncation is enabled. This means we can just turn it on by default rather than only enabling it for "make W=1".
[...]
Here is the summary with links: - [2/9] enetc: avoid truncating error message https://git.kernel.org/netdev/net-next/c/9046d581ed58 - [3/9] qed: avoid truncating work queue length https://git.kernel.org/netdev/net-next/c/954fd908f177 - [4/9] mlx5: avoid truncating error message https://git.kernel.org/netdev/net-next/c/b324a960354b
You are awesome, thank you!
On Tue, 26 Mar 2024 23:37:59 +0100, Arnd Bergmann wrote:
With randconfig build testing, I found only eight files that produce warnings with clang when -Wformat-truncation is enabled. This means we can just turn it on by default rather than only enabling it for "make W=1".
Unfortunately, gcc produces a lot more warnings when the option is enabled, so it's not yet possible to turn it on both both compilers.
[...]
Applied to 6.9/scsi-fixes, thanks!
[7/9] scsi: mylex: fix sysfs buffer lengths https://git.kernel.org/mkp/scsi/c/1197c5b2099f
participants (5)
-
Arnd Bergmann -
Jakub Kicinski -
Martin K. Petersen -
patchwork-bot+netdevbpf＠kernel.org -
Takashi Iwai