From: Thorsten Blum thorsten.blum@linux.dev
[ Upstream commit 8e7d178d06e8937454b6d2f2811fa6a15656a214 ]
In ksmbd_extract_shortname(), strscpy() is incorrectly called with the length of the source string (excluding the NUL terminator) rather than the size of the destination buffer. This results in "__" being copied to 'extension' rather than "___" (two underscores instead of three).
Use the destination buffer size instead to ensure that the string "___" (three underscores) is copied correctly.
Cc: stable@vger.kernel.org Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3") Signed-off-by: Thorsten Blum thorsten.blum@linux.dev Acked-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/smb/server/smb_common.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/smb/server/smb_common.c b/fs/smb/server/smb_common.c index 23537e1b3468..2839c704110c 100644 --- a/fs/smb/server/smb_common.c +++ b/fs/smb/server/smb_common.c @@ -515,7 +515,7 @@ int ksmbd_extract_shortname(struct ksmbd_conn *conn, const char *longname,
p = strrchr(longname, '.'); if (p == longname) { /*name starts with a dot*/ - strscpy(extension, "___", strlen("___")); + strscpy(extension, "___", sizeof(extension)); } else { if (p) { p++;