linux/tools
Jose E. Marchesi 009367099e bpf: Avoid uninitialized value in BPF_CORE_READ_BITFIELD
[Changes from V1:
 - Use a default branch in the switch statement to initialize `val'.]

GCC warns that `val' may be used uninitialized in the
BPF_CRE_READ_BITFIELD macro, defined in bpf_core_read.h as:

	[...]
	unsigned long long val;						      \
	[...]								      \
	switch (__CORE_RELO(s, field, BYTE_SIZE)) {			      \
	case 1: val = *(const unsigned char *)p; break;			      \
	case 2: val = *(const unsigned short *)p; break;		      \
	case 4: val = *(const unsigned int *)p; break;			      \
	case 8: val = *(const unsigned long long *)p; break;		      \
        }       							      \
	[...]
	val;								      \
	}								      \

This patch adds a default entry in the switch statement that sets
`val' to zero in order to avoid the warning, and random values to be
used in case __builtin_preserve_field_info returns unexpected values
for BPF_FIELD_BYTE_SIZE.

Tested in bpf-next master.
No regressions.

Signed-off-by: Jose E. Marchesi <jose.marchesi@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240508101313.16662-1-jose.marchesi@oracle.com
2024-05-08 15:00:55 -07:00
..
accounting
arch tools/include: Sync arm64 asm/cputype.h with the kernel sources 2024-04-11 10:38:29 -07:00
bootconfig
bpf bpftool, selftests/hid/bpf: Fix 29 clang warnings 2024-05-06 14:39:36 -07:00
build perf: build: introduce the libcapstone 2024-02-20 18:06:25 -08:00
certs
cgroup
counter
crypto crypto: ccp - Update return values for some unit tests 2024-02-24 08:41:20 +08:00
debugging
firewire
firmware
gpio
hv hv/hv_kvp_daemon: Handle IPv4 and Ipv6 combination for keyfile format 2024-04-10 21:25:40 +00:00
iio
include bpf: Add support for kprobe session attach 2024-04-30 09:45:53 -07:00
kvm/kvm_stat
laptop
leds
lib bpf: Avoid uninitialized value in BPF_CORE_READ_BITFIELD 2024-05-08 15:00:55 -07:00
memory-model
mm tools/mm: add thpmaps script to dump THP usage info 2024-02-22 10:24:38 -08:00
net/ynl tools: ynl: don't append doc of missing type directly to the type 2024-04-26 17:35:03 -07:00
objtool objtool: Fix compile failure when using the x32 compiler 2024-03-30 22:12:37 +01:00
pci
pcmcia
perf Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-04-25 12:41:37 -07:00
power Turbostat version 2024.04.10 2024-04-10 13:13:27 -07:00
rcu
scripts treewide: remove meaningless assignments in Makefiles 2024-02-23 14:19:07 -08:00
spi
testing bpf: guard BPF_NO_PRESERVE_ACCESS_INDEX in skb_pkt_end.c 2024-05-08 09:56:59 -07:00
thermal
time
tracing tools/rtla: Add -U/--user-load option to timerlat 2024-03-20 05:39:06 +01:00
usb
verification tools/verification: Use tools/build makefiles on rv 2024-03-20 05:39:06 +01:00
virtio tools: virtio: introduce vhost_net_test 2024-03-05 11:38:14 +01:00
wmi
workqueue workqueue: Implement BH workqueues to eventually replace tasklets 2024-02-04 11:28:06 -10:00
Makefile tools/Makefile: remove cgroup target 2024-03-26 11:07:21 -07:00