smb/client: validate new EOF for insert range
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.6.160, 6.12.111, 6.18.53, 7.2.7
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: smb/client: validate new EOF for insert range smb3_insert_range() does not check if the new file size (i_size + len) is valid. This allows FALLOC_FL_INSERT_RANGE to bypass RLIMIT_FSIZE, exceed s_maxbytes, or produce a size outside the loff_t range. Use check_add_overflow() to calculate the new EOF. Validate it with inode_newsize_ok() before modifying the file. Reproducer, using a file on a CIFS mount: bash -c ' FILE=/mnt/cifs/repro trap "" SIGXFSZ ulimit -f 3072 # RLIMIT_FSIZE = 3 MiB A regular write is stopped at 3 MiB. dd if=/dev/zero of="$FILE" bs=1M count=4 status=none stat -c "size after write: %s" "$FILE" Insert 2 MiB into a 2 MiB file. truncate -s 2M "$FILE" fallocate -i -o 0 -l 2M "$FILE" stat -c "size after insert: %s" "$FILE" ' Before this change, the regular write stops at the 3 MiB limit, but insert range grows the file to 4 MiB: dd: error writing '/mnt/cifs/repro': File too large size after write: 3145728 size after insert: 4194304 After this change, insert range also fails at the limit and leaves the 2 MiB file unchanged: dd: error writing '/mnt/cifs/repro': File too large size after write: 3145728 fallocate: fallocate failed: File too large size after insert: 2097152
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 7fe6fe95b936084dce6eedcc2cccadf96eafae73 · fixed in b7f2e33d9f5db7b8e6e5e0a5a93d0c5e31870356; From 7fe6fe95b936084dce6eedcc2cccadf96eafae73 · fixed in 7c2c69045aa76ccaa7f16f1478eb312130ce4951; From 7fe6fe95b936084dce6eedcc2cccadf96eafae73 · fixed in bc7602b9082ef195d913c4c16fa9853dd262333e; From 7fe6fe95b936084dce6eedcc2cccadf96eafae73 · fixed in f8cbfe3a3fcee7d991fd223f660f3e5df13221cf; From 7fe6fe95b936084dce6eedcc2cccadf96eafae73 · fixed in 1519dc88c87f5346dae0464d7d6da1b6bf1f6e8e
- Linux Linux
5.13
- KernelLinux
From 5.13.0 · fixed in 6.6.160; From 6.7.0 · fixed in 6.12.111; From 6.13.0 · fixed in 6.18.53; From 6.19.0 · fixed in 7.2.7