• David Howells's avatar
    rxrpc: Fix -Wframe-larger-than= warnings from on-stack crypto · 1db88c53
    David Howells authored
    rxkad sometimes triggers a warning about oversized stack frames when
    building with clang for a 32-bit architecture:
    
    net/rxrpc/rxkad.c:243:12: error: stack frame size of 1088 bytes in function 'rxkad_secure_packet' [-Werror,-Wframe-larger-than=]
    net/rxrpc/rxkad.c:501:12: error: stack frame size of 1088 bytes in function 'rxkad_verify_packet' [-Werror,-Wframe-larger-than=]
    
    The problem is the combination of SYNC_SKCIPHER_REQUEST_ON_STACK() in
    rxkad_verify_packet()/rxkad_secure_packet() with the relatively large
    scatterlist in rxkad_verify_packet_1()/rxkad_secure_packet_encrypt().
    
    The warning does not show up when using gcc, which does not inline the
    functions as aggressively, but the problem is still the same.
    
    Allocate the cipher buffers from the slab instead, caching the allocated
    packet crypto request memory used for DATA packet crypto in the rxrpc_call
    struct.
    
    Fixes: 17926a79 ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
    Reported-by: default avatarArnd Bergmann <arnd@arndb.de>
    Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
    Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
    cc: Herbert Xu <herbert@gondor.apana.org.au>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    1db88c53
insecure.c 2.17 KB