From: Theodore Ts'o <tytso@mit.edu>
Date: Sat, 17 Jul 2021 02:31:26 +0000 (-0400)
Subject: libe2p: use stat to prevent calling EXT2_IOC_[GS]ETFLAGS on devices
X-Git-Tag: v1.46.3~15
X-Git-Url: https://git.whamcloud.com/?a=commitdiff_plain;h=a3f844da91f0c01209a5d778a5af57fabe245332;p=tools%2Fe2fsprogs.git

libe2p: use stat to prevent calling EXT2_IOC_[GS]ETFLAGS on devices

Some devices can react badly to the EXT2_IOC_[GS]ETFLAGS ioctls, since
ioctl codes are not guaranteed to be unique across different device
drivers and file systems.

Addresses-Debian-Bug: #986332
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
---

diff --git a/lib/e2p/fgetflags.c b/lib/e2p/fgetflags.c
index 93e130c..24a7166 100644
--- a/lib/e2p/fgetflags.c
+++ b/lib/e2p/fgetflags.c
@@ -79,14 +79,26 @@ int fgetflags (const char * name, unsigned long * flags)
 	*flags = f;
 	return (save_errno);
 #elif HAVE_EXT2_IOCTLS
+	struct stat buf;
 	int fd, r, f, save_errno = 0;
 
+	if (!stat(name, &buf) &&
+	    !S_ISREG(buf.st_mode) && !S_ISDIR(buf.st_mode)) {
+		errno = EOPNOTSUPP;
+		return -1;
+	}
 	fd = open(name, OPEN_FLAGS);
 	if (fd == -1) {
 		if (errno == ELOOP || errno == ENXIO)
 			errno = EOPNOTSUPP;
 		return -1;
 	}
+	if (!fstat(fd, &buf) &&
+	    !S_ISREG(buf.st_mode) && !S_ISDIR(buf.st_mode)) {
+		close(fd);
+		errno = EOPNOTSUPP;
+		return -1;
+	}
 	r = ioctl(fd, EXT2_IOC_GETFLAGS, &f);
 	if (r == -1) {
 		if (errno == ENOTTY)
diff --git a/lib/e2p/fsetflags.c b/lib/e2p/fsetflags.c
index 6455e38..d865d24 100644
--- a/lib/e2p/fsetflags.c
+++ b/lib/e2p/fsetflags.c
@@ -80,14 +80,26 @@ int fsetflags (const char * name, unsigned long flags)
 	int f = (int) flags;
 	return syscall(SYS_fsctl, name, EXT2_IOC_SETFLAGS, &f, 0);
 #elif HAVE_EXT2_IOCTLS
+	struct stat buf;
 	int fd, r, f, save_errno = 0;
 
+	if (!stat(name, &buf) &&
+	    !S_ISREG(buf.st_mode) && !S_ISDIR(buf.st_mode)) {
+		errno = EOPNOTSUPP;
+		return -1;
+	}
 	fd = open(name, OPEN_FLAGS);
 	if (fd == -1) {
 		if (errno == ELOOP || errno == ENXIO)
 			errno = EOPNOTSUPP;
 		return -1;
 	}
+	if (!fstat(fd, &buf) &&
+	    !S_ISREG(buf.st_mode) && !S_ISDIR(buf.st_mode)) {
+		close(fd);
+		errno = EOPNOTSUPP;
+		return -1;
+	}
 	f = (int) flags;
 	r = ioctl(fd, EXT2_IOC_SETFLAGS, &f);
 	if (r == -1) {