len0rd/dtc
1
0
Fork 0
mirror of https://github.com/dgibson/dtc.git synced 2026-07-10 13:29:48 -04:00
Code Issues Projects Releases Packages Wiki Activity Actions 2

libfdt: fix UBSAN null pointer in fdt_property()

Browse source 
fdt_property() unconditionally calls memcpy(ptr, val, len) even when
len is zero and val is NULL.  This is a legitimate calling convention
for adding empty FDT properties such as "interrupt-controller", which
carry no payload.

However, compilers that treat memcpy as nonnull on its pointer arguments
will fire UBSAN before observing that len is zero.

Guard the memcpy() with a check on len so it is skipped entirely when
there is no payload to copy, bringing the code in line with the
nonnull contract.

Signed-off-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
This commit is contained in:
Oleksii Kurochko 2026-05-19 17:45:43 +02:00
parent 2164019f84
commit 6c5e89aa55
1 changed files with 2 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

3
libfdt/fdt_sw.c
View file

@ -330,7 +330,8 @@ int fdt_property(void *fdt, const char *name, const void *val, int len)
ret = fdt_property_placeholder(fdt, name, len, &ptr);
if (ret)
return ret;
memcpy(ptr, val, len);
if (len)
memcpy(ptr, val, len);
return 0;
}