TWxSoftware/twx-linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

um: Store full CSGSFS and SS register from mcontext

Browse Source 
[ Upstream commit cef721e0d5 ]

Doing this allows using registers as retrieved from an mcontext to be
pushed to a process using PTRACE_SETREGS.

It is not entirely clear to me why CSGSFS was masked. Doing so creates
issues when using the mcontext as process state in seccomp and simply
copying the register appears to work perfectly fine for ptrace.

Signed-off-by: Benjamin Berg <benjamin@sipsolutions.net>
Link: https://patch.msgid.link/20250224181827.647129-2-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Benjamin Berg
2025-02-24 19:18:19 +01:00
committed by Greg Kroah-Hartman
parent 61225b3395
commit 7638182277
1 changed files with 1 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files
arch/x86/um/os-Linux/mcontext.c
+1 -2
View File
@@ -26,7 +26,6 @@ void get_regs_from_mc(struct uml_pt_regs *regs, mcontext_t *mc)
COPY(RIP);
COPY2(EFLAGS, EFL);
COPY2(CS, CSGSFS);
regs->gp[CS / sizeof(unsigned long)] &= 0xffff;
regs->gp[CS / sizeof(unsigned long)] |= 3;
regs->gp[SS / sizeof(unsigned long)] = mc->gregs[REG_CSGSFS] >> 48;
#endif
}