Commit e76a0143 authored by Björn Töpel's avatar Björn Töpel Committed by Andrii Nakryiko
Browse files

selftests/bpf: Bump and validate MAX_SYMS 



BPF tests that load /proc/kallsyms, e.g. bpf_cookie, will perform a
buffer overrun if the number of syms on the system is larger than
MAX_SYMS.

Bump the MAX_SYMS to 400000, and add a runtime check that bails out if
the maximum is reached.

Signed-off-by: default avatarBjörn Töpel <bjorn@rivosinc.com>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Acked-by: default avatarStanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20230706142228.1128452-1-bjorn@kernel.org
parent b625030c

tools/testing/selftests/bpf/trace_helpers.c

+4 −1
Original line number Diff line number Diff line
@@ -18,7 +18,7 @@ 
#define TRACEFS_PIPE	"/sys/kernel/tracing/trace_pipe"

#define DEBUGFS_PIPE	"/sys/kernel/debug/tracing/trace_pipe"



#define MAX_SYMS 300000

#define MAX_SYMS 400000

static struct ksym syms[MAX_SYMS];

static int sym_cnt;
@@ -46,6 +46,9 @@ int load_kallsyms_refresh(void) 
			break;

		if (!addr)

			continue;

		if (i >= MAX_SYMS)

			return -EFBIG;



		syms[i].addr = (long) addr;

		syms[i].name = strdup(func);

		i++;