orangefs_prepare_debugfs_help_string() constructs the debugfs help text in a dynamically allocated buffer using repeated strlcat() calls across keyword loops, rescanning the buffer on every append.
In preparation for removing the deprecated strlcat() API[1], use struct seq_buf to build the help string. This tracks the write position across the loops, allows formatting each keyword line with a single seq_buf_printf() call, and checks for truncation via seq_buf_has_overflowed(). Additionally, replace the final strlcat() call that copies the completed string into debug_help_string with strscpy(). Link: https://github.com/KSPP/linux/issues/370 [1] Cc: [email protected] Assisted-by: Gemini:gemini-2.0-flash-exp [shell_command_run, editor_update_file] Signed-off-by: Bill Wendling <[email protected]> --- Cc: Russell King <[email protected]> Cc: Huacai Chen <[email protected]> Cc: WANG Xuerui <[email protected]> Cc: Thomas Bogendoerfer <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: Helge Deller <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dave Hansen <[email protected]> Cc: [email protected] Cc: "H. Peter Anvin" <[email protected]> Cc: Ian Abbott <[email protected]> Cc: H Hartley Sweeten <[email protected]> Cc: Tony Luck <[email protected]> Cc: Maarten Lankhorst <[email protected]> Cc: Maxime Ripard <[email protected]> Cc: Thomas Zimmermann <[email protected]> Cc: David Airlie <[email protected]> Cc: Simona Vetter <[email protected]> Cc: Matthew Brost <[email protected]> Cc: "Thomas Hellström" <[email protected]> Cc: Rodrigo Vivi <[email protected]> Cc: Dmitry Torokhov <[email protected]> Cc: Matthias Schwarzott <[email protected]> Cc: Mauro Carvalho Chehab <[email protected]> Cc: Tony Nguyen <[email protected]> Cc: Przemek Kitszel <[email protected]> Cc: Andrew Lunn <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: Arend van Spriel <[email protected]> Cc: Rob Herring <[email protected]> Cc: Saravana Kannan <[email protected]> Cc: Krzysztof Kozlowski <[email protected]> Cc: Sylwester Nawrocki <[email protected]> Cc: Peter Griffin <[email protected]> Cc: Alim Akhtar <[email protected]> Cc: Linus Walleij <[email protected]> Cc: Anil Gurumurthy <[email protected]> Cc: Sudarsana Kalluru <[email protected]> Cc: "Martin K. Petersen" <[email protected]> Cc: Trond Myklebust <[email protected]> Cc: Anna Schumaker <[email protected]> Cc: Mike Marshall <[email protected]> Cc: Martin Brandenburg <[email protected]> Cc: Kees Cook <[email protected]> Cc: Jiri Pirko <[email protected]> Cc: Simon Horman <[email protected]> Cc: Chuck Lever <[email protected]> Cc: Jeff Layton <[email protected]> Cc: NeilBrown <[email protected]> Cc: Olga Kornievskaia <[email protected]> Cc: Dai Ngo <[email protected]> Cc: Tom Talpey <[email protected]> Cc: Jaroslav Kysela <[email protected]> Cc: Takashi Iwai <[email protected]> Cc: Bill Wendling <[email protected]> Cc: Andrew Morton <[email protected]> Cc: "Mike Rapoport (Microsoft)" <[email protected]> Cc: Kanglong Wang <[email protected]> Cc: Tiezhu Yang <[email protected]> Cc: Qiang Ma <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Pengpeng Hou <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: Breno Leitao <[email protected]> Cc: Thorsten Blum <[email protected]> Cc: Harshit Mogalapalli <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Lyude Paul <[email protected]> Cc: Ashutosh Desai <[email protected]> Cc: Imre Deak <[email protected]> Cc: Dmitry Baryshkov <[email protected]> Cc: Johan Hovold <[email protected]> Cc: Johannes Berg <[email protected]> Cc: Miri Korenblit <[email protected]> Cc: Alexander Stein <[email protected]> Cc: Cryolitia PukNgae <[email protected]> Cc: Jiaming Zhang <[email protected]> Cc: Will Porter <[email protected]> Cc: Cen Zhang <[email protected]> Cc: "Cássio Gabriel" <[email protected]> Cc: Rong Zhang <[email protected]> Cc: Arun Raghavan <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] --- fs/orangefs/orangefs-debugfs.c | 36 +++++++++++++--------------------- 1 file changed, 14 insertions(+), 22 deletions(-) diff --git a/fs/orangefs/orangefs-debugfs.c b/fs/orangefs/orangefs-debugfs.c index 9f94919a6bc6..6e2f9887eab4 100644 --- a/fs/orangefs/orangefs-debugfs.c +++ b/fs/orangefs/orangefs-debugfs.c @@ -37,6 +37,7 @@ */ #include <linux/debugfs.h> #include <linux/slab.h> +#include <linux/seq_buf.h> #include <linux/uaccess.h> @@ -623,10 +624,10 @@ int orangefs_prepare_debugfs_help_string(int at_boot) char *client_title = "Client Debug Keywords:\n"; char *kernel_title = "Kernel Debug Keywords:\n"; size_t string_size = DEBUG_HELP_STRING_SIZE; - size_t result_size; size_t i; char *new; int rc = -EINVAL; + struct seq_buf s; gossip_debug(GOSSIP_UTILS_DEBUG, "%s: start\n", __func__); @@ -640,17 +641,14 @@ int orangefs_prepare_debugfs_help_string(int at_boot) goto out; } + seq_buf_init(&s, new, string_size); + /* - * strlcat(dst, src, size) will append at most - * "size - strlen(dst) - 1" bytes of src onto dst, - * null terminating the result, and return the total - * length of the string it tried to create. - * * We'll just plow through here building our new debug - * help string and let strlcat take care of assuring that + * help string and let seq_buf take care of assuring that * dst doesn't overflow. */ - strlcat(new, client_title, string_size); + seq_buf_puts(&s, client_title); if (!at_boot) { @@ -665,24 +663,18 @@ int orangefs_prepare_debugfs_help_string(int at_boot) goto out; } - for (i = 0; i < cdm_element_count; i++) { - strlcat(new, "\t", string_size); - strlcat(new, cdm_array[i].keyword, string_size); - strlcat(new, "\n", string_size); - } + for (i = 0; i < cdm_element_count; i++) + seq_buf_printf(&s, "\t%s\n", cdm_array[i].keyword); } - strlcat(new, "\n", string_size); - strlcat(new, kernel_title, string_size); + seq_buf_puts(&s, "\n"); + seq_buf_puts(&s, kernel_title); - for (i = 0; i < num_kmod_keyword_mask_map; i++) { - strlcat(new, "\t", string_size); - strlcat(new, s_kmod_keyword_mask_map[i].keyword, string_size); - result_size = strlcat(new, "\n", string_size); - } + for (i = 0; i < num_kmod_keyword_mask_map; i++) + seq_buf_printf(&s, "\t%s\n", s_kmod_keyword_mask_map[i].keyword); /* See if we tried to put too many bytes into "new"... */ - if (result_size >= string_size) { + if (seq_buf_has_overflowed(&s)) { kfree(new); goto out; } @@ -692,7 +684,7 @@ int orangefs_prepare_debugfs_help_string(int at_boot) } else { mutex_lock(&orangefs_help_file_lock); memset(debug_help_string, 0, DEBUG_HELP_STRING_SIZE); - strlcat(debug_help_string, new, string_size); + strscpy(debug_help_string, new, DEBUG_HELP_STRING_SIZE); mutex_unlock(&orangefs_help_file_lock); kfree(new); } -- 2.55.0.1032.g73a4cd73de-goog
