Re: [PATCH v7 02/13] syscalls: Create unified partial table for all archs

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:
- [Medium] scripts: unconditional max assignment in gen_hdr() truncates syscall bounds
- [Low] scripts: global nxt variable in gen_tbl() prevents processing overlapping tables
- [Low] scripts: unhandled grep exit status under set -e aborts build and leaks files
--

commit ee189db3abdfc2d74c8d015dc09705528a8d78b7
Author: André Almeida <andrealmeid@igalia.com>

syscalls: Create unified partial table for all archs

This commit creates a unified partial table for syscalls shared across all
architectures. It adapts generation scripts to use this table, allowing every
new syscall to be added to a single file. It also creates special ABIs and
Makefiles flags to support different architectural entry points.

> diff --git a/scripts/syscallhdr.sh b/scripts/syscallhdr.sh
> index bad1ab606a0fb..8f7dfcf19a4c5 100755
> --- a/scripts/syscallhdr.sh
> +++ b/scripts/syscallhdr.sh
[ ... ]
> @@ -69,13 +76,35 @@ guard=_UAPI_ASM_$(basename "$outfile" |
>  	sed -e 'y/abcdefghijklmnopqrstuvwxyz/ABCDEFGHIJKLMNOPQRSTUVWXYZ/' \
>  	-e 's/[^A-Z0-9_]/_/g' -e 's/__/_/g')
[ ... ]
> +max=0
> +# gen_hdr(infile)
> +gen_hdr() {
> +	input=$1
> +	tmpfile=$(mktemp)
>  
> -	max=0
> -	while read nr abi name native compat ; do
> +	grep -E "^[0-9A-Fa-fXx]+[[:space:]]+$abis" "$input" > $tmpfile

[Severity: Low]
Does this unhandled grep exit status abort the build and leak files?

Since this script runs under set -e, if the specified ABI has no entries in the
parsed table, grep returns exit status 1.

Due to set -e, the shell will immediately kill the script, bypassing the
rm $tmpfile cleanup at the end of the function.

> +	while read nr abi name native compat; do
>  
>  		max=$nr

[Severity: Medium]
Will this unconditional max assignment truncate the syscall bounds?

gen_hdr() sequentially processes the arch-specific table and then the common
table. The global max variable is unconditionally assigned max=$nr.

Because the common table is processed last, its maximum number will permanently
overwrite any higher maximum previously read from the arch table.

>  
> @@ -84,15 +113,21 @@ grep -E "^[0-9A-Fa-fXx]+[[:space:]]+$abis" "$infile" | {
>  		fi
>  
>  		echo "#define __NR_$prefix$name $nr"
> -	done
>  
> -	if [ -n "$emit_nr" ]; then
> -		echo
> -		echo "#ifdef __KERNEL__"
> -		echo "#define __NR_${prefix}syscalls $(($max + 1))"
> -		echo "#endif"
> -	fi
> +	done < $tmpfile
> +	rm $tmpfile
> +}
[ ... ]
> diff --git a/scripts/syscalltbl.sh b/scripts/syscalltbl.sh
> index c4b1f85c2dd63..70da0039ab22f 100755
> --- a/scripts/syscalltbl.sh
> +++ b/scripts/syscalltbl.sh
[ ... ]
> @@ -52,12 +59,16 @@ outfile="$2"
>  
>  nxt=0
>  
> -grep -E "^[0-9]+[[:space:]]+$abis" "$infile" | {
> +# gen_tbl(infile)
> +gen_tbl() {
> +	input=$1
> +	tmpfile=$(mktemp)
>  
> +	grep -E "^[0-9A-Fa-fXx]+[[:space:]]+$abis" "$input" > $tmpfile

[Severity: Low]
Can this unhandled grep exit status abort the build and leak files?

Similar to gen_hdr(), this script also runs under set -e. If the grep command
finds zero matches, it exits with 1, which causes set -e to kill the script
here before the cleanup routine can run.

>  	while read nr abi name native compat noreturn; do
>  
>  		if [ $nxt -gt $nr ]; then
> -			echo "error: $infile: syscall table is not sorted or duplicates the same syscall number" >&2
> +			echo "error: $input: syscall table is not sorted or duplicates the same syscall number" >&2
>  			exit 1
>  		fi

[Severity: Low]
Does this global nxt variable in gen_tbl() prevent processing overlapping
tables?

The validation check enforces a strict monotonic increase in syscall numbers.
gen_tbl() maintains a global nxt variable across sequential file invocations.

If the first file's maximum exceeds the second file's minimum, processing the
second file will immediately fail this validation check and exit.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260917-tonyk-syscall_table-v7-0-f4cd8f8e3265@igalia.com?part=2