From: Samanta Navarro <ferivoz@riseup.net>
Date: Fri, 13 Jan 2023 11:51:52 +0000 (+0000)
Subject: lib/blkdev: set errno in more cases
X-Git-Tag: v2.39-rc1~160^2~1
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=2f7450f6cb401f754f298fc8d7c5cdd5b31ade11;p=thirdparty%2Futil-linux.git

lib/blkdev: set errno in more cases

Applications evaluate errno in case of a -1 return value. Examples
within util-linux are fsck.cramfs and mkfs.minix. Set errno more often
to offer reasonable error codes to the application and user.

Signed-off-by: Samanta Navarro <ferivoz@riseup.net>
---

diff --git a/lib/blkdev.c b/lib/blkdev.c
index 954de454e6..757f3e818b 100644
--- a/lib/blkdev.c
+++ b/lib/blkdev.c
@@ -8,6 +8,7 @@
 #include <sys/stat.h>
 #include <sys/file.h>
 #include <sys/ioctl.h>
+#include <errno.h>
 #include <unistd.h>
 #include <stdint.h>
 
@@ -60,8 +61,10 @@ blkdev_find_size (int fd) {
 	uintmax_t high, low = 0;
 
 	for (high = 1024; blkdev_valid_offset (fd, high); ) {
-		if (high == UINTMAX_MAX)
+		if (high == UINTMAX_MAX) {
+			errno = EFBIG;
 			return -1;
+		}
 
 		low = high;
 
@@ -167,8 +170,10 @@ blkdev_get_size(int fd, unsigned long long *bytes)
 			*bytes = st.st_size;
 			return 0;
 		}
-		if (!S_ISBLK(st.st_mode))
+		if (!S_ISBLK(st.st_mode)) {
+			errno = ENOTBLK;
 			return -1;
+		}
 	}
 
 	*bytes = blkdev_find_size(fd);