From 3a1b2a74c6ec7f116ce0ac07a2cf0438e246e5f5 Mon Sep 17 00:00:00 2001 From: Simon Wilkinson Date: Fri, 3 Jul 2009 14:18:32 +0000 Subject: [PATCH] STABLE14-linux-vnop-return-value-cleanup-20090703 LICENSE IPL10 rework all linux vnode ops so the vulnerability we previously had can't recur later just because someone makes a change that would leak a negative error (cherry picked from commit ebc4f737ae8f8056de1a7f80828a6173ebb24292) --- src/afs/LINUX/osi_vnodeops.c | 80 ++++++++++++++++++++++-------------- 1 file changed, 50 insertions(+), 30 deletions(-) diff --git a/src/afs/LINUX/osi_vnodeops.c b/src/afs/LINUX/osi_vnodeops.c index 143159f1e..97670baa0 100644 --- a/src/afs/LINUX/osi_vnodeops.c +++ b/src/afs/LINUX/osi_vnodeops.c @@ -58,6 +58,22 @@ extern struct vcache *afs_globalVp; extern int afs_notify_change(struct dentry *dp, struct iattr *iattrp); + +/* This function converts a positive error code from AFS into a negative + * code suitable for passing into the Linux VFS layer. It checks that the + * error code is within the permissable bounds for the ERR_PTR mechanism. + * + * _All_ error codes which come from the AFS layer should be passed through + * this function before being returned to the kernel. + */ + +static inline int afs_convert_code(int code) { + if ((code >= 0) && (code <= MAX_ERRNO)) + return -code; + else + return -EIO; +} + static ssize_t afs_linux_read(struct file *fp, char *buf, size_t count, loff_t * offp) { @@ -77,7 +93,7 @@ afs_linux_read(struct file *fp, char *buf, size_t count, loff_t * offp) code = afs_VerifyVCache(vcp, &treq); if (code) - code = -code; + code = afs_convert_code(code); else { osi_FlushPages(vcp, credp); /* ensure stale pages are gone */ AFS_GUNLOCK(); @@ -127,7 +143,7 @@ afs_linux_write(struct file *fp, const char *buf, size_t count, loff_t * offp) afs_FakeOpen(vcp); ReleaseWriteLock(&vcp->lock); if (code) - code = -code; + code = afs_convert_code(code); else { AFS_GUNLOCK(); #ifdef DO_SYNC_READ @@ -182,19 +198,25 @@ afs_linux_readdir(struct file *fp, void *dirbuf, filldir_t filldir) code = afs_InitReq(&treq, credp); crfree(credp); - if (code) + if (code) { + code = afs_convert_code(code); goto out1; + } afs_InitFakeStat(&fakestat); code = afs_EvalFakeStat(&avc, &fakestat, &treq); - if (code) + if (code) { + code = afs_convert_code(code); goto out; + } /* update the cache entry */ tagain: code = afs_VerifyVCache(avc, &treq); - if (code) + if (code) { + code = afs_convert_code(code); goto out; + } /* get a reference to the entire directory */ tdc = afs_GetDCache(avc, (afs_size_t) 0, &treq, &origOffset, &tlen, 1); @@ -375,7 +397,7 @@ out: return code; out_err: - code = -code; + code = afs_convert_code(code); goto out; } @@ -397,7 +419,7 @@ afs_linux_open(struct inode *ip, struct file *fp) #endif crfree(credp); - return -code; + return afs_convert_code(code); } static int @@ -418,7 +440,7 @@ afs_linux_release(struct inode *ip, struct file *fp) #endif crfree(credp); - return -code; + return afs_convert_code(code); } static int @@ -442,7 +464,7 @@ afs_linux_fsync(struct file *fp, struct dentry *dp) unlock_kernel(); #endif crfree(credp); - return -code; + return afs_convert_code(code); } @@ -502,7 +524,7 @@ afs_linux_lock(struct file *fp, int cmd, struct file_lock *flp) flp->fl_end = flock.l_start + flock.l_len; crfree(credp); - return -code; + return afs_convert_code(code); } #ifdef STRUCT_FILE_OPERATIONS_HAS_FLOCK @@ -552,7 +574,7 @@ afs_linux_flock(struct file *fp, int cmd, struct file_lock *flp) { flp->fl_pid = flock.l_pid; crfree(credp); - return -code; + return afs_convert_code(code); } #endif @@ -600,7 +622,7 @@ out: AFS_GUNLOCK(); crfree(credp); - return -code; + return afs_convert_code(code); } #if !defined(AFS_LINUX24_ENV) @@ -757,7 +779,7 @@ afs_linux_revalidate(struct dentry *dp) #endif crfree(credp); - return -code; + return afs_convert_code(code); } #if defined(AFS_LINUX26_ENV) @@ -1008,7 +1030,7 @@ afs_linux_create(struct inode *dip, struct dentry *dp, int mode) unlock_kernel(); #endif crfree(credp); - return -code; + return afs_convert_code(code); } /* afs_linux_lookup */ @@ -1090,14 +1112,12 @@ afs_linux_lookup(struct inode *dip, struct dentry *dp) #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,2,10) if (code == ENOENT) return ERR_PTR(0); - else if ((code >= 0) && (code <= MAX_ERRNO)) - return ERR_PTR(-code); - else - return ERR_PTR(-EIO); + else + return ERR_PTR(afs_convert_code(code)); #else if (code == ENOENT) code = 0; - return -code; + return afs_convert_code(code); #endif } @@ -1119,7 +1139,7 @@ afs_linux_link(struct dentry *olddp, struct inode *dip, struct dentry *newdp) AFS_GUNLOCK(); crfree(credp); - return -code; + return afs_convert_code(code); } static int @@ -1199,7 +1219,7 @@ out: unlock_kernel(); #endif crfree(credp); - return -code; + return afs_convert_code(code); } @@ -1221,7 +1241,7 @@ afs_linux_symlink(struct inode *dip, struct dentry *dp, const char *target) code = afs_symlink(VTOAFS(dip), name, &vattr, target, credp); AFS_GUNLOCK(); crfree(credp); - return -code; + return afs_convert_code(code); } static int @@ -1258,7 +1278,7 @@ afs_linux_mkdir(struct inode *dip, struct dentry *dp, int mode) unlock_kernel(); #endif crfree(credp); - return -code; + return afs_convert_code(code); } static int @@ -1287,7 +1307,7 @@ afs_linux_rmdir(struct inode *dip, struct dentry *dp) } crfree(credp); - return -code; + return afs_convert_code(code); } @@ -1336,7 +1356,7 @@ afs_linux_rename(struct inode *oldip, struct dentry *olddp, #endif crfree(credp); - return -code; + return afs_convert_code(code); } @@ -1359,7 +1379,7 @@ afs_linux_ireadlink(struct inode *ip, char *target, int maxlen, uio_seg_t seg) if (!code) return maxlen - tuio.uio_resid; else - return -code; + return afs_convert_code(code); } #if !defined(USABLE_KERNEL_PAGE_SYMLINK_CACHE) @@ -1538,7 +1558,7 @@ afs_linux_readpage(struct file *fp, struct page *pp) } crfree(credp); - return -code; + return afs_convert_code(code); } @@ -1601,7 +1621,7 @@ afs_linux_writepage_sync(struct inode *ip, struct page *pp, if (!afs_InitReq(&treq, credp)) code = afs_DoPartialWrite(vcp, &treq); } - code = code ? -code : count - tuio.uio_resid; + code = code ? afs_convert_code(code) : count - tuio.uio_resid; vcp->states &= ~CPageWrite; ReleaseWriteLock(&vcp->lock); @@ -1714,7 +1734,7 @@ afs_linux_updatepage(struct file *fp, struct page *pp, unsigned long offset, ReleaseWriteLock(&vcp->lock); } - code = code ? -code : count - tuio.uio_resid; + code = code ? afs_convert_code(code) : count - tuio.uio_resid; afs_Trace4(afs_iclSetp, CM_TRACE_UPDATEPAGE, ICL_TYPE_POINTER, vcp, ICL_TYPE_POINTER, pp, ICL_TYPE_INT32, page_count(pp), ICL_TYPE_INT32, code); @@ -1752,7 +1772,7 @@ afs_linux_permission(struct inode *ip, int mode) AFS_GUNLOCK(); crfree(credp); - return -code; + return afs_convert_code(code); } #if defined(AFS_LINUX24_ENV) && !(LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28) && defined(HAVE_WRITE_BEGIN)) -- 2.39.5