linux-stable.git/tools/lib, branch v5.15.151

libsubcmd: Fix memory leak in uniq()

2024-02-23T07:54:51+00:00

[ Upstream commit ad30469a841b50dbb541df4d6971d891f703c297 ]

uniq() will write one command name over another causing the overwritten
string to be leaked. Fix by doing a pass that removes duplicates and a
second that removes the holes.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Chenyuan Mi 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/r/20231208000515.1693746-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

libbpf: Fix NULL pointer dereference in bpf_object__collect_prog_relos

2024-02-23T07:54:45+00:00

[ Upstream commit fc3a5534e2a8855427403113cbeb54af5837bbe0 ]

An issue occurred while reading an ELF file in libbpf.c during fuzzing:

	Program received signal SIGSEGV, Segmentation fault.
	0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206
	4206 in libbpf.c
	(gdb) bt
	#0 0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206
	#1 0x000000000094f9d6 in bpf_object.collect_relos () at libbpf.c:6706
	#2 0x000000000092bef3 in bpf_object_open () at libbpf.c:7437
	#3 0x000000000092c046 in bpf_object.open_mem () at libbpf.c:7497
	#4 0x0000000000924afa in LLVMFuzzerTestOneInput () at fuzz/bpf-object-fuzzer.c:16
	#5 0x000000000060be11 in testblitz_engine::fuzzer::Fuzzer::run_one ()
	#6 0x000000000087ad92 in tracing::span::Span::in_scope ()
	#7 0x00000000006078aa in testblitz_engine::fuzzer::util::walkdir ()
	#8 0x00000000005f3217 in testblitz_engine::entrypoint::main::{{closure}} ()
	#9 0x00000000005f2601 in main ()
	(gdb)

scn_data was null at this code(tools/lib/bpf/src/libbpf.c):

	if (rel->r_offset % BPF_INSN_SZ || rel->r_offset >= scn_data->d_size) {

The scn_data is derived from the code above:

	scn = elf_sec_by_idx(obj, sec_idx);
	scn_data = elf_sec_data(obj, scn);

	relo_sec_name = elf_sec_str(obj, shdr->sh_name);
	sec_name = elf_sec_name(obj, scn);
	if (!relo_sec_name || !sec_name)// don't check whether scn_data is NULL
		return -EINVAL;

In certain special scenarios, such as reading a malformed ELF file,
it is possible that scn_data may be a null pointer

Signed-off-by: Mingyi Zhang 
Signed-off-by: Xin Liu 
Signed-off-by: Changye Wu 
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Daniel Borkmann 
Acked-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20231221033947.154564-1-liuxin350@huawei.com
Signed-off-by: Sasha Levin

libapi: Add missing linux/types.h header to get the __u64 type on io.h

2024-01-25T22:52:50+00:00

[ Upstream commit af76b2dec0984a079d8497bfa37d29a9b55932e1 ]

There are functions using __u64, so we need to have the linux/types.h
header otherwise we'll break when its not included before api/io.h.

Fixes: e95770af4c4a280f ("tools api: Add a lightweight buffered reading api")
Reviewed-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: https://lore.kernel.org/lkml/ZWjDPL+IzPPsuC3X@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

libbpf: fix offsetof() and container_of() to work with CO-RE

2023-07-23T11:46:49+00:00

[ Upstream commit bdeeed3498c7871c17465bb4f11d1bc67f9098af ]

It seems like __builtin_offset() doesn't preserve CO-RE field
relocations properly. So if offsetof() macro is defined through
__builtin_offset(), CO-RE-enabled BPF code using container_of() will be
subtly and silently broken.

To avoid this problem, redefine offsetof() and container_of() in the
form that works with CO-RE relocations more reliably.

Fixes: 5fbc220862fc ("tools/libpf: Add offsetof/container_of macro in bpf_helpers.h")
Reported-by: Lennart Poettering 
Signed-off-by: Andrii Nakryiko 
Acked-by: Yonghong Song 
Link: https://lore.kernel.org/r/20230509065502.2306180-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

libbpf: btf_dump_type_data_check_overflow needs to consider BTF_MEMBER_BITFIELD_SIZE

2023-07-23T11:46:49+00:00

[ Upstream commit c39028b333f3a3a765c5c0b9726b8e38aedf0ba1 ]

The btf_dump/struct_data selftest is failing with:

  [...]
  test_btf_dump_struct_data:FAIL:unexpected return value dumping fs_context unexpected unexpected return value dumping fs_context: actual -7 != expected 264
  [...]

The reason is in btf_dump_type_data_check_overflow(). It does not use
BTF_MEMBER_BITFIELD_SIZE from the struct's member (btf_member). Instead,
it is using the enum size which is 4. It had been working till the recent
commit 4e04143c869c ("fs_context: drop the unused lsm_flags member")
removed an integer member which also removed the 4 bytes padding at the
end of the fs_context. Missing this 4 bytes padding exposed this bug. In
particular, when btf_dump_type_data_check_overflow() reaches the member
'phase', -E2BIG is returned.

The fix is to pass bit_sz to btf_dump_type_data_check_overflow(). In
btf_dump_type_data_check_overflow(), it does a different size check when
bit_sz is not zero.

The current fs_context:

[3600] ENUM 'fs_context_purpose' encoding=UNSIGNED size=4 vlen=3
	'FS_CONTEXT_FOR_MOUNT' val=0
	'FS_CONTEXT_FOR_SUBMOUNT' val=1
	'FS_CONTEXT_FOR_RECONFIGURE' val=2
[3601] ENUM 'fs_context_phase' encoding=UNSIGNED size=4 vlen=7
	'FS_CONTEXT_CREATE_PARAMS' val=0
	'FS_CONTEXT_CREATING' val=1
	'FS_CONTEXT_AWAITING_MOUNT' val=2
	'FS_CONTEXT_AWAITING_RECONF' val=3
	'FS_CONTEXT_RECONF_PARAMS' val=4
	'FS_CONTEXT_RECONFIGURING' val=5
	'FS_CONTEXT_FAILED' val=6
[3602] STRUCT 'fs_context' size=264 vlen=21
	'ops' type_id=3603 bits_offset=0
	'uapi_mutex' type_id=235 bits_offset=64
	'fs_type' type_id=872 bits_offset=1216
	'fs_private' type_id=21 bits_offset=1280
	'sget_key' type_id=21 bits_offset=1344
	'root' type_id=781 bits_offset=1408
	'user_ns' type_id=251 bits_offset=1472
	'net_ns' type_id=984 bits_offset=1536
	'cred' type_id=1785 bits_offset=1600
	'log' type_id=3621 bits_offset=1664
	'source' type_id=42 bits_offset=1792
	'security' type_id=21 bits_offset=1856
	's_fs_info' type_id=21 bits_offset=1920
	'sb_flags' type_id=20 bits_offset=1984
	'sb_flags_mask' type_id=20 bits_offset=2016
	's_iflags' type_id=20 bits_offset=2048
	'purpose' type_id=3600 bits_offset=2080 bitfield_size=8
	'phase' type_id=3601 bits_offset=2088 bitfield_size=8
	'need_free' type_id=67 bits_offset=2096 bitfield_size=1
	'global' type_id=67 bits_offset=2097 bitfield_size=1
	'oldapi' type_id=67 bits_offset=2098 bitfield_size=1

Fixes: 920d16af9b42 ("libbpf: BTF dumper support for typed data")
Signed-off-by: Martin KaFai Lau 
Signed-off-by: Daniel Borkmann 
Acked-by: Yonghong Song 
Link: https://lore.kernel.org/bpf/20230428013638.1581263-1-martin.lau@linux.dev
Signed-off-by: Sasha Levin

libbpf: Fix single-line struct definition output in btf_dump

2023-04-20T10:13:54+00:00

[ Upstream commit 872aec4b5f635d94111d48ec3c57fbe078d64e7d ]

btf_dump APIs emit unnecessary tabs when emitting struct/union
definition that fits on the single line. Before this patch we'd get:

struct blah {};

This patch fixes this and makes sure that we get more natural:

struct blah {};

Fixes: 44a726c3f23c ("bpftool: Print newline before '}' for struct with padding only fields")
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20221212211505.558851-2-andrii@kernel.org
Signed-off-by: Sasha Levin

bpftool: Print newline before '}' for struct with padding only fields

2023-04-13T14:48:27+00:00

[ Upstream commit 44a726c3f23cf762ef4ce3c1709aefbcbe97f62c ]

btf_dump_emit_struct_def attempts to print empty structures at a
single line, e.g. `struct empty {}`. However, it has to account for a
case when there are no regular but some padding fields in the struct.
In such case `vlen` would be zero, but size would be non-zero.

E.g. here is struct bpf_timer from vmlinux.h before this patch:

 struct bpf_timer {
 	long: 64;
	long: 64;};

And after this patch:

 struct bpf_dynptr {
 	long: 64;
	long: 64;
 };

Signed-off-by: Eduard Zingerman 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20221001104425.415768-1-eddyz87@gmail.com
Signed-off-by: Sasha Levin

libbpf: Fix btf_dump's packed struct determination

2023-04-05T09:25:02+00:00

[ Upstream commit 4fb877aaa179dcdb1676d55216482febaada457e ]

Fix bug in btf_dump's logic of determining if a given struct type is
packed or not. The notion of "natural alignment" is not needed and is
even harmful in this case, so drop it altogether. The biggest difference
in btf_is_struct_packed() compared to its original implementation is
that we don't really use btf__align_of() to determine overall alignment
of a struct type (because it could be 1 for both packed and non-packed
struct, depending on specifci field definitions), and just use field's
actual alignment to calculate whether any field is requiring packing or
struct's size overall necessitates packing.

Add two simple test cases that demonstrate the difference this change
would make.

Fixes: ea2ce1ba99aa ("libbpf: Fix BTF-to-C converter's padding logic")
Reported-by: Eduard Zingerman 
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Daniel Borkmann 
Acked-by: Eduard Zingerman 
Link: https://lore.kernel.org/bpf/20221215183605.4149488-1-andrii@kernel.org
Signed-off-by: Sasha Levin

libbpf: Fix BTF-to-C converter's padding logic

2023-04-05T09:25:01+00:00

[ Upstream commit ea2ce1ba99aa6a60c8d8a706e3abadf3de372163 ]

Turns out that btf_dump API doesn't handle a bunch of tricky corner
cases, as reported by Per, and further discovered using his testing
Python script ([0]).

This patch revamps btf_dump's padding logic significantly, making it
more correct and also avoiding unnecessary explicit padding, where
compiler would pad naturally. This overall topic turned out to be very
tricky and subtle, there are lots of subtle corner cases. The comments
in the code tries to give some clues, but comments themselves are
supposed to be paired with good understanding of C alignment and padding
rules. Plus some experimentation to figure out subtle things like
whether `long :0;` means that struct is now forced to be long-aligned
(no, it's not, turns out).

Anyways, Per's script, while not completely correct in some known
situations, doesn't show any obvious cases where this logic breaks, so
this is a nice improvement over the previous state of this logic.

Some selftests had to be adjusted to accommodate better use of natural
alignment rules, eliminating some unnecessary padding, or changing it to
`type: 0;` alignment markers.

Note also that for when we are in between bitfields, we emit explicit
bit size, while otherwise we use `: 0`, this feels much more natural in
practice.

Next patch will add few more test cases, found through randomized Per's
script.

[0] https://lore.kernel.org/bpf/85f83c333f5355c8ac026f835b18d15060725fcb.camel@ericsson.com/

Reported-by: Per Sundström XP
Signed-off-by: Andrii Nakryiko
Signed-off-by: Daniel Borkmann
Link: https://lore.kernel.org/bpf/20221212211505.558851-6-andrii@kernel.org
Signed-off-by: Sasha Levin

libbpf: Fix alen calculation in libbpf_nla_dump_errormsg()

2023-03-10T08:39:16+00:00

[ Upstream commit 17bcd27a08a21397698edf143084d7c87ce17946 ]

The code assumes that everything that comes after nlmsgerr are nlattrs.
When calculating their size, it does not account for the initial
nlmsghdr. This may lead to accessing uninitialized memory.

Fixes: bbf48c18ee0c ("libbpf: add error reporting in XDP")
Signed-off-by: Ilya Leoshkevich 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20230210001210.395194-8-iii@linux.ibm.com
Signed-off-by: Sasha Levin