Commit 54233a42 authored by Arnd Bergmann's avatar Arnd Bergmann
Browse files

uretprobe: change syscall number, again 



Despite multiple attempts to get the syscall number assignment right
for the newly added uretprobe syscall, we ended up with a bit of a mess:

 - The number is defined as 467 based on the assumption that the
   xattrat family of syscalls would use 463 through 466, but those
   did not make it into 6.11.

 - The include/uapi/asm-generic/unistd.h file still lists the number
   463, but the new scripts/syscall.tbl that was supposed to have the
   same data lists 467 instead as the number for arc, arm64, csky,
   hexagon, loongarch, nios2, openrisc and riscv. None of these
   architectures actually provide a uretprobe syscall.

 - All the other architectures (powerpc, arm, mips, ...) don't list
   this syscall at all.

There are two ways to make it consistent again: either list it with
the same syscall number on all architectures, or only list it on x86
but not in scripts/syscall.tbl and asm-generic/unistd.h.

Based on the most recent discussion, it seems like we won't need it
anywhere else, so just remove the inconsistent assignment and instead
move the x86 number to the next available one in the architecture
specific range, which is 335.

Fixes: 5c28424e ("syscalls: Fix to add sys_uretprobe to syscall.tbl")
Fixes: 190fec72 ("uprobe: Wire up uretprobe system call")
Fixes: 63ded110 ("uprobe: Change uretprobe syscall scope and number")
Acked-by: default avatarMasami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: default avatarJiri Olsa <jolsa@kernel.org>
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
parent b07ce24d

arch/x86/entry/syscalls/syscall_64.tbl

+1 −1
Original line number Diff line number Diff line
@@ -344,6 +344,7 @@ 
332	common	statx			sys_statx

333	common	io_pgetevents		sys_io_pgetevents

334	common	rseq			sys_rseq

335	common	uretprobe		sys_uretprobe

# don't use numbers 387 through 423, add new calls after the last

# 'common' entry

424	common	pidfd_send_signal	sys_pidfd_send_signal
@@ -385,7 +386,6 @@ 
460	common	lsm_set_self_attr	sys_lsm_set_self_attr

461	common	lsm_list_modules	sys_lsm_list_modules

462 	common  mseal			sys_mseal

467	common	uretprobe		sys_uretprobe



#

# Due to a historical design error, certain syscalls are numbered differently

include/uapi/asm-generic/unistd.h

+1 −4
Original line number Diff line number Diff line
@@ -841,11 +841,8 @@ __SYSCALL(__NR_lsm_list_modules, sys_lsm_list_modules) 
#define __NR_mseal 462

__SYSCALL(__NR_mseal, sys_mseal)



#define __NR_uretprobe 463

__SYSCALL(__NR_uretprobe, sys_uretprobe)



#undef __NR_syscalls

#define __NR_syscalls 464

#define __NR_syscalls 463



/*

 * 32 bit systems traditionally used different

scripts/syscall.tbl

+0 −1
Original line number Diff line number Diff line
@@ -402,4 +402,3 @@ 
460	common	lsm_set_self_attr		sys_lsm_set_self_attr

461	common	lsm_list_modules		sys_lsm_list_modules

462	common	mseal				sys_mseal
 
467	common	uretprobe			sys_uretprobe

tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c

+1 −1
Original line number Diff line number Diff line
@@ -216,7 +216,7 @@ static void test_uretprobe_regs_change(void) 
}



#ifndef __NR_uretprobe

#define __NR_uretprobe 467

#define __NR_uretprobe 335

#endif



__naked unsigned long uretprobe_syscall_call_1(void)