um: Use POSIX ucontext_t instead of struct ucontext

[ Upstream commit 4d1a535b8ec5e74b42dfd9dc809142653b2597f6 ]

glibc 2.26 removed the 'struct ucontext' to "improve" POSIX compliance
and break programs, including User Mode Linux. Fix User Mode Linux
by using POSIX ucontext_t.

This fixes:

arch/um/os-Linux/signal.c: In function 'hard_handler':
arch/um/os-Linux/signal.c:163:22: error: dereferencing pointer to incomplete type 'struct ucontext'
  mcontext_t *mc = &uc->uc_mcontext;
arch/x86/um/stub_segv.c: In function 'stub_segv_handler':
arch/x86/um/stub_segv.c:16:13: error: dereferencing pointer to incomplete type 'struct ucontext'
          &uc->uc_mcontext);

Cc: stable@vger.kernel.org
Signed-off-by: Krzysztof Mazur <krzysiek@podlesie.net>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>

diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c
index 7b605e4dfffa91305e763e7698832edcbf80d3bd..2ac6a7e5a1792967c8b55ac9b347eb0dd7894ba3 100644 (file)
--- a/arch/um/os-Linux/signal.c
+++ b/arch/um/os-Linux/signal.c
@@ -135,7 +135,7 @@ static void (*handlers[_NSIG])(int sig, struct siginfo *si, mcontext_t *mc) = {
 
 static void hard_handler(int sig, siginfo_t *si, void *p)
 {
-       struct ucontext *uc = p;
+       ucontext_t *uc = p;
        mcontext_t *mc = &uc->uc_mcontext;
        unsigned long pending = 1UL << sig;
 

diff --git a/arch/x86/um/stub_segv.c b/arch/x86/um/stub_segv.c
index 1518d2805ae81733eb0629989f4d39ae595502c2..fd6825537b97aaaf5d5ea4dea6d52e2341344c3b 100644 (file)
--- a/arch/x86/um/stub_segv.c
+++ b/arch/x86/um/stub_segv.c
@@ -10,7 +10,7 @@
 void __attribute__ ((__section__ (".__syscall_stub")))
 stub_segv_handler(int sig, siginfo_t *info, void *p)
 {
-       struct ucontext *uc = p;
+       ucontext_t *uc = p;
 
        GET_FAULTINFO_FROM_MC(*((struct faultinfo *) STUB_DATA),
                              &uc->uc_mcontext);