7e7241f620
Upstream commit: 808a84a8b81468b517a4d721fdc62069cb8c211f
- Fix underallocation of abort_msg_s struct (CVE-2025-0395)
- x86/string: Fixup alignment of main loop in str{n}cmp-evex [BZ #32212]
- x86: Improve large memset perf with non-temporal stores [RHEL-29312]
- x86: Avoid integer truncation with large cache sizes (bug 32470)
- math: Exclude internal math symbols for tests [BZ #32414]
- malloc: add indirection for malloc(-like) functions in tests [BZ #32366]
- Pass -nostdlib -nostartfiles together with -r [BZ #31753]
- nptl: initialize cpu_id_start prior to rseq registration
- nptl: initialize rseq area prior to registration
56 lines
2.3 KiB
Diff
56 lines
2.3 KiB
Diff
commit 9a0e174a39a3a65f628c6a55e29fe35f6d67bf42
|
|
Author: Michael Jeanson <mjeanson@efficios.com>
|
|
Date: Thu Nov 7 22:23:49 2024 +0100
|
|
|
|
nptl: initialize rseq area prior to registration
|
|
|
|
Per the rseq syscall documentation, 3 fields are required to be
|
|
initialized by userspace prior to registration, they are 'cpu_id',
|
|
'rseq_cs' and 'flags'. Since we have no guarantee that 'struct pthread'
|
|
is cleared on all architectures, explicitly set those 3 fields prior to
|
|
registration.
|
|
|
|
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
|
|
Reviewed-by: Florian Weimer <fweimer@redhat.com>
|
|
(cherry picked from commit 97f60abd25628425971f07e9b0e7f8eec0741235)
|
|
|
|
diff --git a/nptl/descr.h b/nptl/descr.h
|
|
index 4697f633e16c7359..a83df327e4bcba2e 100644
|
|
--- a/nptl/descr.h
|
|
+++ b/nptl/descr.h
|
|
@@ -417,6 +417,8 @@ struct pthread
|
|
{
|
|
uint32_t cpu_id_start;
|
|
uint32_t cpu_id;
|
|
+ uint64_t rseq_cs;
|
|
+ uint32_t flags;
|
|
};
|
|
char pad[32]; /* Original rseq area size. */
|
|
} rseq_area __attribute__ ((aligned (32)));
|
|
diff --git a/sysdeps/unix/sysv/linux/rseq-internal.h b/sysdeps/unix/sysv/linux/rseq-internal.h
|
|
index 7ea935b4adab8c20..37a8f630b6519ff0 100644
|
|
--- a/sysdeps/unix/sysv/linux/rseq-internal.h
|
|
+++ b/sysdeps/unix/sysv/linux/rseq-internal.h
|
|
@@ -51,11 +51,21 @@ rseq_register_current_thread (struct pthread *self, bool do_rseq)
|
|
/* The initial implementation used only 20 bytes out of 32,
|
|
but still expected size 32. */
|
|
size = RSEQ_AREA_SIZE_INITIAL;
|
|
+
|
|
+ /* Initialize the rseq fields that are read by the kernel on
|
|
+ registration, there is no guarantee that struct pthread is
|
|
+ cleared on all architectures. */
|
|
+ THREAD_SETMEM (self, rseq_area.cpu_id, RSEQ_CPU_ID_UNINITIALIZED);
|
|
+ THREAD_SETMEM (self, rseq_area.rseq_cs, 0);
|
|
+ THREAD_SETMEM (self, rseq_area.flags, 0);
|
|
+
|
|
int ret = INTERNAL_SYSCALL_CALL (rseq, &self->rseq_area,
|
|
size, 0, RSEQ_SIG);
|
|
if (!INTERNAL_SYSCALL_ERROR_P (ret))
|
|
return true;
|
|
}
|
|
+ /* When rseq is disabled by tunables or the registration fails, inform
|
|
+ userspace by setting 'cpu_id' to RSEQ_CPU_ID_REGISTRATION_FAILED. */
|
|
THREAD_SETMEM (self, rseq_area.cpu_id, RSEQ_CPU_ID_REGISTRATION_FAILED);
|
|
return false;
|
|
}
|