fault-injection: enhance failcmd to exit on non-hex address input

The failcmd.sh script in the fault-injection toolkit does not currently
validate whether the provided address is in hexadecimal format.  This can
lead to silent failures if the address is sourced from places like
`/proc/kallsyms`, which omits the '0x' prefix, potentially causing users
to operate under incorrect assumptions.

Introduce a new function, `exit_if_not_hex`, which checks the format of
the provided address and exits with an error message if the address is not
a valid hexadecimal number.

This enhancement prevents users from running the command with improperly
formatted addresses, thus improving the robustness and usability of the
failcmd tool.

Link: https://lkml.kernel.org/r/20240729084512.3349928-1-leitao@debian.org
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Breno Leitao 2024-07-29 01:45:08 -07:00 committed by Andrew Morton
parent 588661fd87
commit 11ee88a0f9

View File

@ -64,6 +64,14 @@ ENVIRONMENT
EOF
}
exit_if_not_hex() {
local value="$1"
if ! [[ $value =~ ^0x[0-9a-fA-F]+$ ]]; then
echo "Error: The provided value '$value' is not a valid hexadecimal number." >&2
exit 1
fi
}
if [ $UID != 0 ]; then
echo must be run as root >&2
exit 1
@ -160,18 +168,22 @@ while true; do
shift 2
;;
--require-start)
exit_if_not_hex "$2"
echo $2 > $FAULTATTR/require-start
shift 2
;;
--require-end)
exit_if_not_hex "$2"
echo $2 > $FAULTATTR/require-end
shift 2
;;
--reject-start)
exit_if_not_hex "$2"
echo $2 > $FAULTATTR/reject-start
shift 2
;;
--reject-end)
exit_if_not_hex "$2"
echo $2 > $FAULTATTR/reject-end
shift 2
;;