/* * linux/fs/isofs/namei.c * * (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem. * * (C) 1991 Linus Torvalds - minix filesystem */ #include #include "isofs.h" /* * ok, we cannot use strncmp, as the name is not in our data space. * Thus we'll have to use isofs_match. No big problem. Match also makes * some sanity tests. */ static int isofs_cmp(struct dentry *dentry, const char *compare, int dlen) { struct qstr qstr; qstr.name = compare; qstr.len = dlen; if (likely(!dentry->d_op)) return dentry->d_name.len != dlen || memcmp(dentry->d_name.name, compare, dlen); return dentry->d_op->d_compare(NULL, dentry->d_name.len, dentry->d_name.name, &qstr); } /* * isofs_find_entry() * * finds an entry in the specified directory with the wanted name. It * returns the inode number of the found entry, or 0 on error. */ static unsigned long isofs_find_entry(struct inode *dir, struct dentry *dentry, unsigned long *block_rv, unsigned long *offset_rv, char *tmpname, struct iso_directory_record *tmpde) { unsigned long bufsize = ISOFS_BUFFER_SIZE(dir); unsigned char bufbits = ISOFS_BUFFER_BITS(dir); unsigned long block, f_pos, offset, block_saved, offset_saved; struct buffer_head *bh = NULL; struct isofs_sb_info *sbi = ISOFS_SB(dir->i_sb); if (!ISOFS_I(dir)->i_first_extent) return 0; f_pos = 0; offset = 0; block = 0; while (f_pos < dir->i_size) { struct iso_directory_record *de; int de_len, match, i, dlen; char *dpnt; if (!bh) { bh = isofs_bread(dir, block); if (!bh) return 0; } de = (struct iso_directory_record *) (bh->b_data + offset); de_len = *(unsigned char *) de; if (!de_len) { brelse(bh); bh = NULL; f_pos = (f_pos + ISOFS_BLOCK_SIZE) & ~(ISOFS_BLOCK_SIZE - 1); block = f_pos >> bufbits; offset = 0; continue; } block_saved = bh->b_blocknr; offset_saved = offset; offset += de_len; f_pos += de_len; /* Make sure we have a full directory entry */ if (offset >= bufsize) { int slop = bufsize - offset + de_len; memcpy(tmpde, de, slop); offset &= bufsize - 1; block++; brelse(bh); bh = NULL; if (offset) { bh = isofs_bread(dir, block); if (!bh) return 0; memcpy((void *) tmpde + slop, bh->b_data, offset); } de = tmpde; } dlen = de->name_len[0]; dpnt = de->name; /* Basic sanity check, whether name doesn't exceed dir entry */ if (de_len < dlen + sizeof(struct iso_directory_record)) { printk(KERN_NOTICE "iso9660: Corrupted directory entry" " in block %lu of inode %lu\n", block, dir->i_ino); return 0; } if (sbi->s_rock && ((i = get_rock_ridge_filename(de, tmpname, dir)))) { dlen = i; /* possibly -1 */ dpnt = tmpname; #ifdef CONFIG_JOLIET } else if (sbi->s_joliet_level) { dlen = get_joliet_filename(de, tmpname, dir); dpnt = tmpname; #endif } else if (sbi->s_mapping == 'a') { dlen = get_acorn_filename(de, tmpname, dir); dpnt = tmpname; } else if (sbi->s_mapping == 'n') { dlen = isofs_name_translate(de, tmpname, dir); dpnt = tmpname; } /* * Skip hidden or associated files unless hide or showassoc, * respectively, is set */ match = 0; if (dlen > 0 && (!sbi->s_hide || (!(de->flags[-sbi->s_high_sierra] & 1))) && (sbi->s_showassoc || (!(de->flags[-sbi->s_high_sierra] & 4)))) { if (dpnt && (dlen > 1 || dpnt[0] > 1)) match = (isofs_cmp(dentry, dpnt, dlen) == 0); } if (match) { isofs_normalize_block_and_offset(de, &block_saved, &offset_saved); *block_rv = block_saved; *offset_rv = offset_saved; brelse(bh); return 1; } } brelse(bh); return 0; } struct dentry *isofs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) { int found; unsigned long uninitialized_var(block); unsigned long uninitialized_var(offset); struct inode *inode; struct page *page; page = alloc_page(GFP_USER); if (!page) return ERR_PTR(-ENOMEM); found = isofs_find_entry(dir, dentry, &block, &offset, page_address(page), 1024 + page_address(page)); __free_page(page); inode = found ? isofs_iget(dir->i_sb, block, offset) : NULL; return d_splice_alias(inode, dentry); } selected='selected'>includemode:
authorDavid S. Miller <davem@davemloft.net>2017-01-30 14:28:22 -0800
committerDavid S. Miller <davem@davemloft.net>2017-01-30 14:28:22 -0800
commit54791b276b4000b307339f269d3bf7db877d536f (patch)
tree1c2616bd373ce5ea28aac2a53e32f5b5834901ce /include/trace/events/target.h
parent5d0e7705774dd412a465896d08d59a81a345c1e4 (diff)
parent047487241ff59374fded8c477f21453681f5995c (diff)
Merge branch 'sparc64-non-resumable-user-error-recovery'
Liam R. Howlett says: ==================== sparc64: Recover from userspace non-resumable PIO & MEM errors A non-resumable error from userspace is able to cause a kernel panic or trap loop due to the setup and handling of the queued traps once in the kernel. This patch series addresses both of these issues. The queues are fixed by simply zeroing the memory before use. PIO errors from userspace will result in a SIGBUS being sent to the user process. The MEM errors form userspace will result in a SIGKILL and also cause the offending pages to be claimed so they are no longer used in future tasks. SIGKILL is used to ensure that the process does not try to coredump and result in an attempt to read the memory again from within kernel space. Although there is a HV call to scrub the memory (mem_scrub), there is no easy way to guarantee that the real memory address(es) are not used by other tasks. Clearing the error with mem_scrub would zero the memory and cause the other processes to proceed with bad data. The handling of other non-resumable errors remain unchanged and will cause a panic. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/trace/events/target.h')