Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: NFSv4: include MAY_WRITE in open permission mask for O_TRUNC POSIX requires write permission to truncate a file, so an open() that specifies O_TRUNC must be authorized for write access regardless of the O_ACCMODE access mode. nfs_open_permission_mask() builds the access mask passed to nfs_may_open(), which is the local authorization gate for OPENs the client serves itself from a cached write delegation via the can_open_delegated() path in nfs4_try_open_cached(). The mask is derived from O_ACCMODE alone, so an open(O_RDONLY | O_TRUNC) against a file the caller cannot write requests only MAY_READ and passes the local check. The OPEN is then satisfied locally and the truncation is issued to the server as a SETATTR(size=0) over the delegation stateid, which the server accepts under standard write-delegation semantics. POSIX requires that this open fail with EACCES. Include MAY_WRITE in the mask whenever O_TRUNC is set so the local check matches the access the server would have enforced.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected af22f94ae02ab9dd4fd7fe628c8434a59cc293be before 4817c8974315b666e895b7d1bb83cd3664c323b1; affected af22f94ae02ab9dd4fd7fe628c8434a59cc293be before cb148a2762d644bff1894728e8835a9a4b84f9ea; affected af22f94ae02ab9dd4fd7fe628c8434a59cc293be before 30fdf4df6c3c00efec947e4ddf97f0fdd4473628; affected af22f94ae02ab9dd4fd7fe628c8434a59cc293be before 22c1fd1355ad4ca27aa7f0fa02719122dd92d9de; affected af22f94ae02ab9dd4fd7fe628c8434a59cc293be before 6bd7d0a06b53c4e797e1a9cea0d2d41aa1b26230; affected af22f94ae02ab9dd4fd7fe628c8434a59cc293be before a937e92c1d00534b5c2e3e9f4381b7e988180797; affected af22f94ae02ab9dd4fd7fe628c8434a59cc293be before e36501b7d4abdcd6d69a7cb901b2f286b7a3d041; affected af22f94ae02ab9dd4fd7fe628c8434a59cc293be before 5140f099ecd8a2f2808b7f7b720ee1bad8468974 |
| Linux / Linux | affected 2.6.24; unaffected 0 before 2.6.24; unaffected 5.10.261 through 5.10.*; unaffected 5.15.212 through 5.15.*; unaffected 6.1.178 through 6.1.*; unaffected 6.6.145 through 6.6.*; unaffected 6.12.96 through 6.12.*; unaffected 6.18.39 through 6.18.*; unaffected 7.1.4 through 7.1.*; unaffected 7.2 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/4817c8974315b666e895b7d1bb83cd3664c323b1
- https://git.kernel.org/stable/c/cb148a2762d644bff1894728e8835a9a4b84f9ea
- https://git.kernel.org/stable/c/30fdf4df6c3c00efec947e4ddf97f0fdd4473628
- https://git.kernel.org/stable/c/22c1fd1355ad4ca27aa7f0fa02719122dd92d9de
- https://git.kernel.org/stable/c/6bd7d0a06b53c4e797e1a9cea0d2d41aa1b26230
- https://git.kernel.org/stable/c/a937e92c1d00534b5c2e3e9f4381b7e988180797
- https://git.kernel.org/stable/c/e36501b7d4abdcd6d69a7cb901b2f286b7a3d041
- https://git.kernel.org/stable/c/5140f099ecd8a2f2808b7f7b720ee1bad8468974
ADP enrichment
No English description supplied.
No references supplied.