From ee1d39bc1573c1ae49ee6b658938b56bbef95a6c Mon Sep 17 00:00:00 2001
From: q66 <q66@chimera-linux.org>
Date: Thu, 9 Nov 2023 20:48:44 +0100
Subject: mntent: unescape octal sequences

As entries in mtab are delimited by spaces, whitespace characters
are escaped as octal sequences. When reading them out, we have to
unescape these sequences to get the proper string.
---
 src/misc/mntent.c | 44 ++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 40 insertions(+), 4 deletions(-)

diff --git a/src/misc/mntent.c b/src/misc/mntent.c
index d404fbe3..e9393883 100644
--- a/src/misc/mntent.c
+++ b/src/misc/mntent.c
@@ -20,6 +20,42 @@ int endmntent(FILE *f)
 	return 1;
 }
 
+static char *unescape_ent(char *beg)
+{
+	char *dest = beg;
+	const char *src = beg;
+	while (*src) {
+		const char *val;
+		unsigned char cval = 0;
+		if (*src != '\\') {
+			*dest++ = *src++;
+			continue;
+		}
+		if (src[1] == '\\') {
+			++src;
+			*dest++ = *src++;
+			continue;
+		}
+		val = src + 1;
+		for (int i = 0; i < 3; ++i) {
+			if (*val >= '0' && *val <= '7') {
+				cval <<= 3;
+				cval += *val++ - '0';
+			} else {
+				break;
+			}
+		}
+		if (cval) {
+			*dest++ = cval;
+			src = val;
+		} else {
+			*dest++ = *src++;
+		}
+	}
+	*dest = 0;
+	return beg;
+}
+
 struct mntent *getmntent_r(FILE *f, struct mntent *mnt, char *linebuf, int buflen)
 {
 	int n[8], use_internal = (linebuf == SENTINEL);
@@ -55,10 +91,10 @@ struct mntent *getmntent_r(FILE *f, struct mntent *mnt, char *linebuf, int bufle
 	linebuf[n[5]] = 0;
 	linebuf[n[7]] = 0;
 
-	mnt->mnt_fsname = linebuf+n[0];
-	mnt->mnt_dir = linebuf+n[2];
-	mnt->mnt_type = linebuf+n[4];
-	mnt->mnt_opts = linebuf+n[6];
+	mnt->mnt_fsname = unescape_ent(linebuf+n[0]);
+	mnt->mnt_dir = unescape_ent(linebuf+n[2]);
+	mnt->mnt_type = unescape_ent(linebuf+n[4]);
+	mnt->mnt_opts = unescape_ent(linebuf+n[6]);
 
 	return mnt;
 }
-- 
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