kernel.git/arch/mips/kernel/ptrace.c, branch linux-4.10.y

mips/ptrace: Preserve previous registers for short regset write

2017-03-31T08:33:42Z

commit d614fd58a2834cfe4efa472c33c8f3ce2338b09b upstream. Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill all the registers, the thread's old registers are preserved. Signed-off-by: Dave Martin Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

Replace with globally

2016-12-24T19:46:01Z

This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*' sed -i -e "s!$PATT!#include !" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro Signed-off-by: Linus Torvalds

MIPS: Fix FCSR Cause bit handling for correct SIGFPE issue

2016-11-04T00:28:41Z

Sanitize FCSR Cause bit handling, following a trail of past attempts: * commit 4249548454f7 ("MIPS: ptrace: Fix FP context restoration FCSR regression"), * commit 443c44032a54 ("MIPS: Always clear FCSR cause bits after emulation"), * commit 64bedffe4968 ("MIPS: Clear [MSA]FPE CSR.Cause after notify_die()"), * commit b1442d39fac2 ("MIPS: Prevent user from setting FCSR cause bits"), * commit b54d2901517d ("Properly handle branch delay slots in connection with signals."). Specifically do not mask these bits out in ptrace(2) processing and send a SIGFPE signal instead whenever a matching pair of an FCSR Cause and Enable bit is seen as execution of an affected context is about to resume. Only then clear Cause bits, and even then do not clear any bits that are set but masked with the respective Enable bits. Adjust Cause bit clearing throughout code likewise, except within the FPU emulator proper where they are set according to IEEE 754 exceptions raised as the operation emulated executed. Do so so that any IEEE 754 exceptions subject to their default handling are recorded like with operations executed by FPU hardware. Signed-off-by: Maciej W. Rozycki Cc: Paul Burton Cc: James Hogan Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/14460/ Signed-off-by: Ralf Baechle

MIPS: ptrace: Also initialize the FP context on individual FCSR writes

2016-11-04T00:28:17Z

Complement commit ac9ad83bc318 ("MIPS: prevent FP context set via ptrace being discarded") and also initialize the FP context whenever FCSR alone is written with a PTRACE_POKEUSR request addressing FPC_CSR, rather than along with the full FPU register set in the case of the PTRACE_SETFPREGS request. Signed-off-by: Maciej W. Rozycki Cc: Paul Burton Cc: James Hogan Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/14459/ Signed-off-by: Ralf Baechle

MIPS/ptrace: run seccomp after ptrace

2016-06-14T17:54:44Z

Close the hole where ptrace can change a syscall out from under seccomp. Signed-off-by: Kees Cook Cc: Ralf Baechle Cc: "Maciej W. Rozycki" Cc: James Hogan Cc: linux-mips@linux-mips.org

seccomp: Add a seccomp_data parameter secure_computing()

2016-06-14T17:54:39Z

Currently, if arch code wants to supply seccomp_data directly to seccomp (which is generally much faster than having seccomp do it using the syscall_get_xyz() API), it has to use the two-phase seccomp hooks. Add it to the easy hooks, too. Cc: linux-arch@vger.kernel.org Signed-off-by: Andy Lutomirski Signed-off-by: Kees Cook

MIPS: ptrace: Prevent writes to read-only FCSR bits

2016-05-13T13:30:25Z

Correct the cases missed with commit 9b26616c8d9d ("MIPS: Respect the ISA level in FCSR handling") and prevent writes to read-only FCSR bits there. This in particular applies to FP context initialisation where any IEEE 754-2008 bits preset by `mips_set_personality_nan' are cleared before the relevant ptrace(2) call takes effect and the PTRACE_POKEUSR request addressing FPC_CSR where no masking of read-only FCSR bits is done. Remove the FCSR clearing from FP context initialisation then and unify PTRACE_POKEUSR/FPC_CSR and PTRACE_SETFPREGS handling, by factoring out code from `ptrace_setfpregs' and calling it from both places. This mostly matters to soft float configurations where the emulator can be switched this way to a mode which should not be accessible and cannot be set with the CTC1 instruction. With hard float configurations any effect is transient anyway as read-only bits will retain their values at the time the FP context is restored. Signed-off-by: Maciej W. Rozycki Cc: stable@vger.kernel.org # v4.0+ Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13239/ Signed-off-by: Ralf Baechle

MIPS: ptrace: Fix FP context restoration FCSR regression

2016-05-13T13:30:25Z

Fix a floating-point context restoration regression introduced with commit 9b26616c8d9d ("MIPS: Respect the ISA level in FCSR handling") that causes a Floating Point exception and consequently a kernel oops with hard float configurations when one or more FCSR Enable and their corresponding Cause bits are set both at a time via a ptrace(2) call. To do so reinstate Cause bit masking originally introduced with commit b1442d39fac2 ("MIPS: Prevent user from setting FCSR cause bits") to address this exact problem and then inadvertently removed from the PTRACE_SETFPREGS request with the commit referred above. Signed-off-by: Maciej W. Rozycki Cc: stable@vger.kernel.org # v4.0+ Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13238/ Signed-off-by: Ralf Baechle

MIPS: Add and use watch register field definitions

2016-05-13T12:02:13Z

The files watch.c and ptrace.c contain various magic masks for WatchLo/WatchHi register fields. Add some definitions to mipsregs.h for these registers and make use of them in both watch.c and ptrace.c, hopefully making them more readable. Signed-off-by: James Hogan Reviewed-by: David Daney Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12729/ Signed-off-by: Ralf Baechle

MIPS: ptrace: Drop cp0_tcstatus from regoffset_table[]

2016-01-24T01:24:24Z

The cp0_tcstatus member of struct pt_regs was removed along with the rest of SMTC in v3.16, commit b633648c5ad3 ("MIPS: MT: Remove SMTC support"), however recent uprobes support in v4.3 added back a reference to it in the regoffset_table[] in ptrace.c. Remove it. Signed-off-by: James Hogan Fixes: 40e084a506eb ("MIPS: Add uprobes support.") Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/11920/ Signed-off-by: Ralf Baechle