diff mbox series

[v2,20/28] um: Move faultinfo extraction into userspace routine

Message ID 20221122100759.208290-21-benjamin@sipsolutions.net
State Not Applicable
Delegated to: Richard Weinberger
Headers show
Series Implement SECCOMP based userland | expand

Commit Message

Benjamin Berg Nov. 22, 2022, 10:07 a.m. UTC 
From: Benjamin Berg <benjamin@sipsolutions.net>

The segv handler is called slightly differently depending on whether
PTRACE_FULL_FAULTINFO is set or not (32bit vs. 64bit). The only
difference is that we don't try to pass the registers and instruction
pointer to the segv handler.

It would be good to either document or remove the difference, but I do
not know why this difference exists.

Signed-off-by: Benjamin Berg <benjamin@sipsolutions.net>
---
 arch/um/os-Linux/skas/process.c | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)
diff mbox series

Patch

diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c
index 1e1c378588ba..1bc7e5aa2fc1 100644
--- a/arch/um/os-Linux/skas/process.c
+++ b/arch/um/os-Linux/skas/process.c
@@ -171,12 +171,6 @@  static void get_skas_faultinfo(int pid, struct faultinfo *fi, unsigned long *aux
 	}
 }
 
-static void handle_segv(int pid, struct uml_pt_regs *regs, unsigned long *aux_fp_regs)
-{
-	get_skas_faultinfo(pid, &regs->faultinfo, aux_fp_regs);
-	segv(regs->faultinfo, 0, 1, NULL);
-}
-
 static void handle_trap(int pid, struct uml_pt_regs *regs)
 {
 	if ((UPT_IP(regs) >= STUB_START) && (UPT_IP(regs) < STUB_END))
@@ -422,13 +416,15 @@  void userspace(struct uml_pt_regs *regs, unsigned long *aux_fp_regs)
 
 			switch (sig) {
 			case SIGSEGV:
-				if (PTRACE_FULL_FAULTINFO) {
-					get_skas_faultinfo(pid,
-							   &regs->faultinfo, aux_fp_regs);
+				get_skas_faultinfo(pid,
+						   &regs->faultinfo, aux_fp_regs);
+
+				if (PTRACE_FULL_FAULTINFO)
 					(*sig_info[SIGSEGV])(SIGSEGV, (struct siginfo *)&si,
 							     regs);
-				}
-				else handle_segv(pid, regs, aux_fp_regs);
+				else
+					segv(regs->faultinfo, 0, 1, NULL);
+
 				break;
 			case SIGTRAP + 0x80:
 				handle_trap(pid, regs);