code.ossystems Code Review - openembedded-core.git/blob

   1 From c1af5643e0df56b92481f7a7bc4110a58e4e5abb Mon Sep 17 00:00:00 2001
   2 From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   3 Date: Fri, 21 Jul 2017 08:22:04 -0400
   4 Subject: [PATCH 3/8] Fix: Sleeping function called from invalid context
   5 Organization: O.S. Systems Software LTDA.
   6
   7 It affects system call instrumentation for accept, accept4 and connect,
   8 only on the x86-64 architecture.
   9
  10 We need to use the LTTng accessing functions to touch user-space memory,
  11 which take care of disabling the page fault handler, so we don't preempt
  12 while in preempt-off context (tracepoints disable preemption).
  13
  14 Fixes #1111
  15
  16 Upstream-Status: Backport [2.9.4]
  17
  18 Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  19 ---
  20  .../x86-64-syscalls-3.10.0-rc7_pointers_override.h | 47 ++++++++++++++--------
  21  1 file changed, 31 insertions(+), 16 deletions(-)
  22
  23 diff --git a/instrumentation/syscalls/headers/x86-64-syscalls-3.10.0-rc7_pointers_override.h b/instrumentation/syscalls/headers/x86-64-syscalls-3.10.0-rc7_pointers_override.h
  24 index 5e91004..6bf5291 100644
  25 --- a/instrumentation/syscalls/headers/x86-64-syscalls-3.10.0-rc7_pointers_override.h
  26 +++ b/instrumentation/syscalls/headers/x86-64-syscalls-3.10.0-rc7_pointers_override.h
  27 @@ -2,7 +2,7 @@
  28
  29  #define OVERRIDE_64_connect
  30  SC_LTTNG_TRACEPOINT_EVENT_CODE(connect,
  31 -       TP_PROTO(sc_exit(long ret,) int fd, struct sockaddr * uservaddr, int addrlen),
  32 +       TP_PROTO(sc_exit(long ret,) int fd, struct sockaddr __user * uservaddr, int addrlen),
  33         TP_ARGS(sc_exit(ret,) fd, uservaddr, addrlen),
  34         TP_locvar(
  35                 __typeof__(uservaddr->sa_family) sa_family;
  36 @@ -16,21 +16,28 @@ SC_LTTNG_TRACEPOINT_EVENT_CODE(connect,
  37                         memset(tp_locvar, 0, sizeof(*tp_locvar));
  38                         if (addrlen < sizeof(tp_locvar->sa_family))
  39                                 goto skip_code;
  40 -                       (void) get_user(tp_locvar->sa_family, &uservaddr->sa_family);
  41 +                       (void) lib_ring_buffer_copy_from_user_check_nofault(&tp_locvar->sa_family,
  42 +                                       &uservaddr->sa_family, sizeof(tp_locvar->sa_family));
  43                         switch (tp_locvar->sa_family) {
  44                         case AF_INET:
  45                                 if (addrlen < sizeof(struct sockaddr_in))
  46                                         goto skip_code;
  47 -                               (void) get_user(tp_locvar->dport, &((struct sockaddr_in *) uservaddr)->sin_port);
  48 -                               (void) get_user(tp_locvar->v4addr, &((struct sockaddr_in *) uservaddr)->sin_addr.s_addr);
  49 +                               (void) lib_ring_buffer_copy_from_user_check_nofault(&tp_locvar->dport,
  50 +                                               &((struct sockaddr_in __user *) uservaddr)->sin_port,
  51 +                                               sizeof(tp_locvar->dport));
  52 +                               (void) lib_ring_buffer_copy_from_user_check_nofault(&tp_locvar->v4addr,
  53 +                                               &((struct sockaddr_in __user *) uservaddr)->sin_addr.s_addr,
  54 +                                               sizeof(tp_locvar->v4addr));
  55                                 tp_locvar->v4addr_len = 4;
  56                                 break;
  57                         case AF_INET6:
  58                                 if (addrlen < sizeof(struct sockaddr_in6))
  59                                         goto skip_code;
  60 -                               (void) get_user(tp_locvar->dport, &((struct sockaddr_in6 *) uservaddr)->sin6_port);
  61 -                               if (copy_from_user(tp_locvar->v6addr,
  62 -                                               &((struct sockaddr_in6 *) uservaddr)->sin6_addr.in6_u.u6_addr8,
  63 +                               (void) lib_ring_buffer_copy_from_user_check_nofault(&tp_locvar->dport,
  64 +                                               &((struct sockaddr_in6 __user *) uservaddr)->sin6_port,
  65 +                                               sizeof(tp_locvar->dport));
  66 +                               if (lib_ring_buffer_copy_from_user_check_nofault(tp_locvar->v6addr,
  67 +                                               &((struct sockaddr_in6 __user *) uservaddr)->sin6_addr.in6_u.u6_addr8,
  68                                                 sizeof(tp_locvar->v6addr)))
  69                                         memset(tp_locvar->v6addr, 0, sizeof(tp_locvar->v6addr));
  70                                 tp_locvar->v6addr_len = 8;
  71 @@ -63,26 +70,34 @@ SC_LTTNG_TRACEPOINT_EVENT_CODE(connect,
  72  #define LTTNG_SYSCALL_ACCEPT_code_pre                                                                                  \
  73         sc_inout(                                                                                                       \
  74                 memset(tp_locvar, 0, sizeof(*tp_locvar));                                                               \
  75 -               (void) get_user(tp_locvar->uaddr_len, upeer_addrlen);                                                   \
  76 +               (void) lib_ring_buffer_copy_from_user_check_nofault(&tp_locvar->uaddr_len,                              \
  77 +                               upeer_addrlen, sizeof(tp_locvar->uaddr_len));                                           \
  78         )                                                                                                               \
  79         sc_out(                                                                                                         \
  80                 if (tp_locvar->uaddr_len < sizeof(tp_locvar->sa_family))                                                \
  81                         goto skip_code;                                                                                 \
  82 -               (void) get_user(tp_locvar->sa_family, &upeer_sockaddr->sa_family);                                      \
  83 +               (void) lib_ring_buffer_copy_from_user_check_nofault(&tp_locvar->sa_family,                              \
  84 +                               &upeer_sockaddr->sa_family, sizeof(tp_locvar->sa_family));                              \
  85                 switch (tp_locvar->sa_family) {                                                                         \
  86                 case AF_INET:                                                                                           \
  87                         if (tp_locvar->uaddr_len < sizeof(struct sockaddr_in))                                          \
  88                                 goto skip_code;                                                                         \
  89 -                       (void) get_user(tp_locvar->sport, &((struct sockaddr_in *) upeer_sockaddr)->sin_port);          \
  90 -                       (void) get_user(tp_locvar->v4addr, &((struct sockaddr_in *) upeer_sockaddr)->sin_addr.s_addr);  \
  91 +                       (void) lib_ring_buffer_copy_from_user_check_nofault(&tp_locvar->sport,                          \
  92 +                                       &((struct sockaddr_in __user *) upeer_sockaddr)->sin_port,                      \
  93 +                                       sizeof(tp_locvar->sport));                                                      \
  94 +                       (void) lib_ring_buffer_copy_from_user_check_nofault(&tp_locvar->v4addr,                         \
  95 +                                       &((struct sockaddr_in __user *) upeer_sockaddr)->sin_addr.s_addr,               \
  96 +                                       sizeof(tp_locvar->v4addr));                                                     \
  97                         tp_locvar->v4addr_len = 4;                                                                      \
  98                         break;                                                                                          \
  99                 case AF_INET6:                                                                                          \
 100                         if (tp_locvar->uaddr_len < sizeof(struct sockaddr_in6))                                         \
 101                                 goto skip_code;                                                                         \
 102 -                       (void) get_user(tp_locvar->sport, &((struct sockaddr_in6 *) upeer_sockaddr)->sin6_port);        \
 103 -                       if (copy_from_user(tp_locvar->v6addr,                                                           \
 104 -                                       &((struct sockaddr_in6 *) upeer_sockaddr)->sin6_addr.in6_u.u6_addr8,            \
 105 +                       (void) lib_ring_buffer_copy_from_user_check_nofault(&tp_locvar->sport,                          \
 106 +                                       &((struct sockaddr_in6 __user *) upeer_sockaddr)->sin6_port,                    \
 107 +                                       sizeof(tp_locvar->sport));                                                      \
 108 +                       if (lib_ring_buffer_copy_from_user_check_nofault(tp_locvar->v6addr,                             \
 109 +                                       &((struct sockaddr_in6 __user *) upeer_sockaddr)->sin6_addr.in6_u.u6_addr8,     \
 110                                         sizeof(tp_locvar->v6addr)))                                                     \
 111                                 memset(tp_locvar->v6addr, 0, sizeof(tp_locvar->v6addr));                                \
 112                         tp_locvar->v6addr_len = 8;                                                                      \
 113 @@ -93,7 +108,7 @@ SC_LTTNG_TRACEPOINT_EVENT_CODE(connect,
 114
 115  #define OVERRIDE_64_accept
 116  SC_LTTNG_TRACEPOINT_EVENT_CODE(accept,
 117 -       TP_PROTO(sc_exit(long ret,) int fd, struct sockaddr * upeer_sockaddr, int * upeer_addrlen),
 118 +       TP_PROTO(sc_exit(long ret,) int fd, struct sockaddr __user * upeer_sockaddr, int __user * upeer_addrlen),
 119         TP_ARGS(sc_exit(ret,) fd, upeer_sockaddr, upeer_addrlen),
 120         TP_locvar(
 121                 LTTNG_SYSCALL_ACCEPT_locvar
 122 @@ -116,7 +131,7 @@ SC_LTTNG_TRACEPOINT_EVENT_CODE(accept,
 123
 124  #define OVERRIDE_64_accept4
 125  SC_LTTNG_TRACEPOINT_EVENT_CODE(accept4,
 126 -       TP_PROTO(sc_exit(long ret,) int fd, struct sockaddr * upeer_sockaddr, int * upeer_addrlen, int flags),
 127 +       TP_PROTO(sc_exit(long ret,) int fd, struct sockaddr __user * upeer_sockaddr, int __user * upeer_addrlen, int flags),
 128         TP_ARGS(sc_exit(ret,) fd, upeer_sockaddr, upeer_addrlen, flags),
 129         TP_locvar(
 130                 LTTNG_SYSCALL_ACCEPT_locvar
 131 --
 132 2.14.1
 133