scripts/faddr2line: Fix "Argument list too long" error

The run_readelf() function reads the entire output of readelf into a
single shell variable. For large object files with extensive debug
information, the size of this variable can exceed the system's
command-line argument length limit.

When this variable is subsequently passed to sed via `echo "${out}"`, it
triggers an "Argument list too long" error, causing the script to fail.

Fix this by redirecting the output of readelf to a temporary file
instead of a variable. The sed commands are then modified to read from
this file, avoiding the argument length limitation entirely.

Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
This commit is contained in:
Pankaj Raghav 2025-09-21 12:03:58 +02:00 committed by Josh Poimboeuf
parent 6b4679fcbf
commit ff5c046648
1 changed files with 9 additions and 4 deletions

View File

@ -111,14 +111,19 @@ find_dir_prefix() {
run_readelf() {
local objfile=$1
local out=$(${READELF} --file-header --section-headers --symbols --wide $objfile)
local tmpfile
tmpfile=$(mktemp)
${READELF} --file-header --section-headers --symbols --wide "$objfile" > "$tmpfile"
# This assumes that readelf first prints the file header, then the section headers, then the symbols.
# Note: It seems that GNU readelf does not prefix section headers with the "There are X section headers"
# line when multiple options are given, so let's also match with the "Section Headers:" line.
ELF_FILEHEADER=$(echo "${out}" | sed -n '/There are [0-9]* section headers, starting at offset\|Section Headers:/q;p')
ELF_SECHEADERS=$(echo "${out}" | sed -n '/There are [0-9]* section headers, starting at offset\|Section Headers:/,$p' | sed -n '/Symbol table .* contains [0-9]* entries:/q;p')
ELF_SYMS=$(echo "${out}" | sed -n '/Symbol table .* contains [0-9]* entries:/,$p')
ELF_FILEHEADER=$(sed -n '/There are [0-9]* section headers, starting at offset\|Section Headers:/q;p' "$tmpfile")
ELF_SECHEADERS=$(sed -n '/There are [0-9]* section headers, starting at offset\|Section Headers:/,$p' "$tmpfile" | sed -n '/Symbol table .* contains [0-9]* entries:/q;p')
ELF_SYMS=$(sed -n '/Symbol table .* contains [0-9]* entries:/,$p' "$tmpfile")
rm -f -- "$tmpfile"
}
check_vmlinux() {