diff options
| author | Josh Law <objecting@objecting.org> | 2026-03-12 19:11:43 +0000 |
|---|---|---|
| committer | Masami Hiramatsu (Google) <mhiramat@kernel.org> | 2026-03-13 17:48:27 +0900 |
| commit | 1120a36bb1e9b9e22de75ecb4ef0b998f73a97f1 (patch) | |
| tree | e3763927e2c2343b13c0196626f0f28e8a2c63ab | |
| parent | 560f763baa0f2c9a44da4294c06af071405ac46f (diff) | |
lib/bootconfig: fix snprintf truncation check in xbc_node_compose_key_after()
snprintf() returns the number of characters that would have been
written excluding the NUL terminator. Output is truncated when the
return value is >= the buffer size, not just > the buffer size.
When ret == size, the current code takes the non-truncated path,
advancing buf by ret and reducing size to 0. This is wrong because
the output was actually truncated (the last character was replaced by
NUL). Fix by using >= so the truncation path is taken correctly.
Link: https://lore.kernel.org/all/20260312191143.28719-4-objecting@objecting.org/
Fixes: 76db5a27a827 ("bootconfig: Add Extra Boot Config support")
Cc: stable@vger.kernel.org
Signed-off-by: Josh Law <objecting@objecting.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
| -rw-r--r-- | lib/bootconfig.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/lib/bootconfig.c b/lib/bootconfig.c index 9c3d59fb96ed..2da049216fe0 100644 --- a/lib/bootconfig.c +++ b/lib/bootconfig.c @@ -316,7 +316,7 @@ int __init xbc_node_compose_key_after(struct xbc_node *root, depth ? "." : ""); if (ret < 0) return ret; - if (ret > size) { + if (ret >= size) { size = 0; } else { size -= ret; |