acrn-kernel/tools/lib
Andrii Nakryiko 0cfbadb153 libbpf: Fix realloc API handling in zero-sized edge cases
[ Upstream commit 8a0260dbf6 ]

realloc() and reallocarray() can either return NULL or a special
non-NULL pointer, if their size argument is zero. This requires a bit
more care to handle NULL-as-valid-result situation differently from
NULL-as-error case. This has caused real issues before ([0]), and just
recently bit again in production when performing bpf_program__attach_usdt().

This patch fixes 4 places that do or potentially could suffer from this
mishandling of NULL, including the reported USDT-related one.

There are many other places where realloc()/reallocarray() is used and
NULL is always treated as an error value, but all those have guarantees
that their size is always non-zero, so those spot don't need any extra
handling.

  [0] d08ab82f59 ("libbpf: Fix double-free when linker processes empty sections")

Fixes: 999783c8bb ("libbpf: Wire up spec management and other arch-independent USDT logic")
Fixes: b63b3c490e ("libbpf: Add bpf_program__set_insns function")
Fixes: 697f104db8 ("libbpf: Support custom SEC() handlers")
Fixes: b126882672 ("libbpf: Change the order of data and text relocations.")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230711024150.1566433-1-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13 09:42:30 +02:00
..
api
bpf libbpf: Fix realloc API handling in zero-sized edge cases 2023-09-13 09:42:30 +02:00
perf
subcmd tools lib subcmd: Add dependency test to install_headers 2023-09-13 09:42:27 +02:00
symbol
thermal
traceevent
argv_split.c
bitmap.c
ctype.c
find_bit.c
hweight.c
list_sort.c
rbtree.c
slab.c
str_error_r.c
string.c
vsprintf.c
zalloc.c