[Minios-devel] [UNIKRAFT PATCH v2 2/2] lib/vfscore: fix null pointer dereferences

[Hugo Lefeuvre <hle@xxxxxxxxxx>]

futimesat allocates buffers via malloc and dereference returned
pointers without NULL checking, causing crashes in OOM situations.

Return EFAULT as this appears to be the most appropriate error code in
this case (the posix definition does include ENOMEM as a possible
error code).

Signed-off-by: Hugo Lefeuvre <hugo.lefeuvre@xxxxxxxxx>
---
Changed since v1:
 - return EFAULT instead of ENOMEM

diff --git a/lib/vfscore/main.c b/lib/vfscore/main.c
index 7a7a54c..8c80ea6 100644
--- a/lib/vfscore/main.c
+++ b/lib/vfscore/main.c
@@ -1803,6 +1803,12 @@ int futimesat(int dirfd, const char *pathname, const 
struct timeval times[2])
 
        /* build absolute path */
        absolute_path = (char*)malloc(PATH_MAX);
+       if (!absolute_path) {
+               fdrop(fp);
+               error = EFAULT;
+               goto out_errno;
+       }
+
        strlcpy(absolute_path, fp->f_dentry->d_mount->m_path, PATH_MAX);
        strlcat(absolute_path, fp->f_dentry->d_path, PATH_MAX);
 
-- 
2.25.1

Attachment: signature.asc
Description: PGP signature

_______________________________________________
Minios-devel mailing list
Minios-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/minios-devel